2 week old embryo. How to determine multiple pregnancy: main signs and methods of determination

Pregnancy is a physiological process in which a new organism develops in the uterus, resulting from fertilization. Pregnancy lasts on average 40 weeks (10 obstetric months).

In the intrauterine development of a child, two periods are distinguished:

1. Embryonic(up to 8 weeks of pregnancy inclusive). At this time, the embryo is called an embryo and acquires characteristic human features;
2. Fetal(from 9 weeks until birth). At this time, the embryo is called a fetus.

The growth of a child, the formation of its organs and systems occurs naturally during various periods of intrauterine development, which is subject to the genetic code embedded in the germ cells and fixed in the process of human evolution.

Embryo development in the first obstetric month (1-4 weeks)

First week (days 1-7)

Pregnancy begins from the moment fertilization- fusion of a mature male cell (sperm) and a female egg. This process usually occurs in the ampullary section of the fallopian tube. After a few hours, the fertilized egg begins to divide exponentially and descends through the fallopian tube into the uterine cavity (this journey takes up to five days).

As a result of division turns out to be a multicellular organism, which is similar to a blackberry (in Latin “morus”), which is why the embryo at this stage is called Morula. Approximately on the 7th day, the morula penetrates the uterine wall (implantation). The villi of the outer cells of the embryo connect with the blood vessels of the uterus, and subsequently the placenta is formed from them. Other outer morula cells give rise to the development of the umbilical cord and membranes. Over time, various tissues and organs of the fetus will develop from the internal cells.

Information At the time of implantation, a woman may have slight bleeding from the genital tract. Such discharge is physiological and does not require treatment.

Second week (8-14 days)

The outer morula cells grow tightly into the lining of the uterus. In the embryo the formation of the umbilical cord and placenta begins, and neural tube, from which the fetal nervous system subsequently develops.

Third week (15-21 days)

The third week of pregnancy is a difficult and important period. At that time important organs and systems begin to form fetus: the rudiments of the respiratory, digestive, circulatory, nervous and excretory systems appear. At the site where the fetal head will soon appear, a wide plate is formed, which will give rise to the brain. On day 21, the baby's heart begins to beat.

Fourth week (22-28 days)

this week laying of fetal organs continues. The rudiments of the intestines, liver, kidneys and lungs are already present. The heart begins to work more intensely and pumps more and more blood through the circulatory system.

From the beginning of the fourth week in the embryo body folds appear, and appears vertebral primordium(chord).

Completed by day 25 neural tube formation.

By the end of the week (approximately 27-28 days) the muscular system and spine are formed, which divides the embryo into two symmetrical halves, both upper and lower limbs.

During this period it begins formation of pits on the head, which will later become the eyes of the fetus.

Development of the embryo in the second obstetric month (5-8 weeks)

Fifth week (29-35 days)

During this period the embryo weighs about 0.4 grams, length 1.5-2.5 mm.

The formation of the following organs and systems begins:

1. Digestive system: liver and pancreas;
2. Respiratory system: larynx, trachea, lungs;
3. Circulatory system;
4. Reproductive system: precursors of germ cells are formed;
5. Sense organs: the formation of the eyes and inner ear continues;
6. Nervous system: the formation of parts of the brain begins.

At that time a faint umbilical cord appears. The formation of limbs continues, the first rudiments of nails appear.

On the face the upper lip and nasal cavities are formed.

Sixth week (36-42 days)

Length embryo during this period is about 4-5 mm.

Starts in the sixth week formation of the placenta. At this stage, it is just beginning to function; blood circulation between it and the embryo has not yet been formed.

Ongoing formation of the brain and its parts. At the sixth week, when performing an encephalogram, it is already possible to record signals from the fetal brain.

Begins formation of facial muscles. The fetal eyes are already more pronounced and uncovered by eyelids that are just beginning to form.

During this period they begin upper limbs change: they lengthen and the rudiments of hands and fingers appear. The lower limbs still remain in their infancy.

Changes in important organs occur:

1. Heart. The division into chambers is completed: ventricles and atria;
2. Urinary system. Primary kidneys have formed, the development of the ureters begins;
3. Digestive system. The formation of sections of the gastrointestinal tract begins: the stomach, small and large intestines. The liver and pancreas had practically completed their development by this period;

Seventh week (43-49 days)

The seventh week is significant in that it is finally The formation of the umbilical cord is completed and uteroplacental circulation is established. Now the breathing and nutrition of the fetus will be carried out due to blood circulation through the vessels of the umbilical cord and placenta.

The embryo is still bent in an arched manner; there is a small tail on the pelvic part of the body. The size of the head is at least half of the embryo. The length from the crown to the sacrum increases by the end of the week up to 13-15 mm.

Ongoing upper limb development. The fingers are visible quite clearly, but their separation from each other has not yet occurred. The child begins to perform spontaneous movements with his hands in response to stimuli.

Fine eyes are formed, already covered with eyelids, which protect them from drying out. The child can open his mouth.

The formation of the nasal fold and nose occurs, two paired elevations are formed on the sides of the head, from which they will begin to develop ears.

Intensive continues development of the brain and its parts.

Eighth week (50-56 days)

The body of the embryo begins to straighten, length from the crown to the coccyx is 15 mm at the beginning of the week and 20-21 mm on day 56.

Ongoing formation of important organs and systems: digestive system, heart, lungs, brain, urinary system, reproductive system (boys develop testicles). The hearing organs are developing.

By the end of the eighth week the child's face becomes familiar to the person: the eyes are well defined, covered with eyelids, the nose, the ears, the formation of the lips is ending.

Intensive growth of the head, upper and lower horses is noted In particular, ossification of the long bones of the arms and legs and the skull develops. The fingers are clearly visible; there is no skin membrane between them.

Additionally At eight weeks the embryonic period of development ends and the fetal period begins. From this time on, the embryo is called a fetus.

Fetal development in the third obstetric month (9-12 weeks)

Ninth week (57-63 days)

At the beginning of the ninth week coccygeal-parietal size fetus is about 22 mm, by the end of the week - 31 mm.

Happening improvement of blood vessels of the placenta, which improves uteroplacental blood flow.

The development of the musculoskeletal system continues. The process of ossification begins, the joints of the toes and hands are formed. The fetus begins to make active movements and can clench its fingers. The head is lowered, the chin is pressed tightly to the chest.

Changes occur in the cardiovascular system. The heart beats up to 150 times per minute and pumps blood through its blood vessels. The composition of blood is still very different from the blood of an adult: it consists only of red blood cells.

Ongoing further growth and development of the brain, cerebellar structures are formed.

The organs of the endocrine system are intensively developing, in particular, the adrenal glands, which produce important hormones.

Improves cartilage tissue: auricles, laryngeal cartilages, vocal cords are being formed.

Tenth week (64-70 days)

By the end of the tenth week fruit length from the coccyx to the crown is 35-40 mm.

Buttocks begin to develop, the previously existing tail disappears. The fetus is in the uterus in a fairly free position in a semi-bent state.

Nervous system development continues. Now the fetus performs not only chaotic movements, but also reflex ones in response to a stimulus. When accidentally touching the walls of the uterus, the child makes movements in response: turns his head, bends or straightens his arms and legs, and pushes to the side. The size of the fetus is still very small, and the woman cannot yet feel these movements.

The sucking reflex is formed, the child begins reflex movements with his lips.

The development of the diaphragm is completed, which will take an active part in breathing.

Eleventh week (71-77 days)

By the end of this week coccygeal-parietal size the fetus increases to 4-5 cm.

The fetal body remains disproportionate: small body, large head, long arms and short legs, bent at all joints and pressed to the stomach.

The placenta has already reached sufficient development and copes with its functions: ensures the supply of oxygen and nutrients to the fetus and removes carbon dioxide and metabolic products.

Further formation of the fetal eyes occurs: At this time, the iris develops, which will later determine the color of the eyes. The eyes are well developed, half-closed or wide open.

Twelfth week (78-84 days)

Coccygeal-parietal size fetus is 50-60 mm.

Goes clearly development of the genital organs according to the female or male type.

Happening further improvement of the digestive system. The intestines are elongated and arranged in loops, like those of an adult. Its periodic contractions begin - peristalsis. The fetus begins to make swallowing movements, swallowing amniotic fluid.

The development and improvement of the fetal nervous system continues. The brain is small in size, but exactly replicates all the structures of the adult brain. The cerebral hemispheres and other sections are well developed. Reflex movements are improved: the fetus can clench and unclench its fingers into a fist, grabs the thumb and actively sucks it.

In fetal blood Not only red blood cells are already present, but the production of white blood cells - leukocytes - also begins.

At this time the child single respiratory movements begin to be recorded. Before birth, the fetus cannot breathe, its lungs do not function, but it makes rhythmic movements of the chest, imitating breathing.

By the end of the week the fetus eyebrows and eyelashes appear, the neck is clearly visible.

Fetal development in the fourth obstetric month (13-16 weeks)

Week 13 (85-91 days)

Coccygeal-parietal size by the end of the week is 70-75 mm. The proportions of the body begin to change: the upper and lower limbs and torso lengthen, the size of the head is no longer so large in relation to the body.

Improvement of the digestive and nervous systems continues. The embryos of baby teeth begin to appear under the upper and lower jaws.

The face is fully formed, the ears, nose and eyes are clearly visible (the eyelids are completely closed).

Week 14 (92-98 days)

Coccygeal-parietal size by the end of the fourteenth week it increases up to 8-9 cm. Body proportions continue to change to more familiar ones. The face has a well-defined forehead, nose, cheeks and chin. The first hair appears on the head (very thin and colorless). The surface of the body is covered with vellus hairs, which retain skin lubrication and thereby perform protective functions.

The musculoskeletal system of the fetus is improved. Bones become stronger. Motor activity increases: the fetus can turn over, bend, and make swimming movements.

Development of the kidneys, bladder and ureters is complete. The kidneys begin to secrete urine, which mixes with the amniotic fluid.

: pancreatic cells begin to work, producing insulin, and pituitary cells.

Changes in the genital organs appear. In boys, the prostate gland forms; in girls, the ovaries migrate into the pelvic cavity. At the fourteenth week, with a good sensitive ultrasound machine, it is already possible to determine the sex of the child.

Fifteenth week (99-105 days)

Coccygeal-parietal size of the fetus is about 10 cm, fruit weight – 70-75 grams. The head still remains quite large, but the growth of the arms, legs and torso begins to outstrip it.

The circulatory system is improved. In the fourth month, a child’s blood type and Rh factor can already be determined. Blood vessels (veins, arteries, capillaries) grow in length and their walls become stronger.

The production of original feces (meconium) begins. This is due to the ingestion of amniotic fluid, which enters the stomach, then into the intestines and fills it.

Fully formed fingers and toes, an individual design appears on them.

Sixteenth week (106-112 days)

The weight of the fetus increases to 100 grams, the coccygeal-parietal size - up to 12 cm.

By the end of the sixteenth week, the fetus is already fully formed, he has all the organs and systems. The kidneys are actively working, a small amount of urine is released into the amniotic fluid every hour.

The skin of the fetus is very thin, subcutaneous fatty tissue is practically absent, so blood vessels are visible through the skin. The skin appears bright red, covered with vellus hairs and grease. Eyebrows and eyelashes are well defined. Nails are formed, but they only cover the edge of the nail phalanx.

Facial muscles are formed, and the fetus begins to “grimace”: frowning of the eyebrows and a semblance of a smile are observed.

Fetal development in the fifth obstetric month (17-20 weeks)

Seventeenth week (days 113-119)

The weight of the fetus is 120-150 grams, the coccygeal-parietal size is 14-15 cm.

The skin remains very thin, but subcutaneous fatty tissue begins to develop under it. The development of baby teeth continues, which are covered with dentin. The embryos of permanent teeth begin to form under them.

There is a reaction to sound stimuli. From this week we can say for sure that the child began to hear. When strong sharp sounds appear, the fetus begins to actively move.

Fetal position changes. The head is raised and is in an almost vertical position. The arms are bent at the elbow joints, the fingers are clenched into a fist almost all the time. Periodically, the child begins to suck his thumb.

The heartbeat becomes clear. From now on, the doctor can listen to him using a stethoscope.

Eighteenth week (120-126 days)

The child's weight is about 200 grams, length - up to 20 cm.

The formation of sleep and wakefulness begins. Most of the time the fetus sleeps, movements stop during this time.

At this time, the woman may already begin to feel the baby moving, especially with repeated pregnancies. The first movements are felt as gentle jolts. A woman may feel more active movements when she is nervous or stressed, which affects the emotional state of the child. At this stage, the norm is about ten episodes of fetal movement per day.

Nineteenth week (127-133 days)

The child’s weight increases to 250-300 grams, body length – to 22-23 cm. The proportions of the body change: the head lags behind the body in growth, the arms and legs begin to lengthen.

Movements become more frequent and noticeable. They can be felt not only by the woman herself, but also by other people by placing their hand on their stomach. Primigravidas at this time can only begin to feel movements.

The endocrine system is improved: the pancreas, pituitary gland, adrenal glands, gonads, thyroid and parathyroid glands are actively functioning.

Blood composition has changed: In addition to erythrocytes and leukocytes, the blood contains monocytes and lymphocytes. The spleen begins to take part in hematopoiesis.

Twentieth week (134-140 days)

Body length increases to 23-25 ​​cm, weight – up to 340 grams.

The fetal skin is still thin, covered with protective lubricant and vellus hairs, which can persist until childbirth. Subcutaneous fatty tissue develops intensively.

Well formed eyes, at twenty weeks the blink reflex begins to appear.

Improved movement coordination: The child confidently brings his finger to his mouth and begins to suck it. Facial expressions are pronounced: the fetus may close its eyes, smile, or frown.

This week all women are already feeling movements., regardless of the number of pregnancies. Movement activity varies throughout the day. When stimuli appear (loud sounds, stuffy rooms), the child begins to move very violently and actively.

Fetal development in the sixth obstetric month (21-24 weeks)

Twenty-first week (days 141-147)

Body weight grows to 380 grams, fetal length – up to 27 cm.

The layer of subcutaneous tissue increases. The skin of the fetus is wrinkled, with many folds.

Fetal movements become more active and tangible. The fetus moves freely in the uterine cavity: it lies head down or buttocks, across the uterus. Can pull on the umbilical cord, push off the walls of the uterus with hands and feet.

Changes in sleep and wakefulness patterns. Now the fetus spends less time sleeping (16-20 hours).

Twenty-second week (148-154 days)

At week 22, the size of the fetus increases to 28 cm, weight - up to 450-500 grams. The size of the head becomes proportional to the body and limbs. The legs are bent almost all the time.

The fetal spine is fully formed: It has all the vertebrae, ligaments and joints. The process of strengthening bones continues.

Improves the fetal nervous system: The brain already contains all the nerve cells (neurons) and has a mass of about 100 grams. The child begins to take an interest in his body: he feels his face, arms, legs, tilts his head, brings his fingers to his mouth.

Heart size increases significantly, the functionality of the cardiovascular system is improved.

Twenty-third week (155-161 days)

The length of the fetal body is 28-30 cm, weight is about 500 grams. Pigment begins to be synthesized in the skin, resulting in the skin becoming bright red. The subcutaneous fatty tissue is still quite thin, as a result the child looks very thin and wrinkled. The lubricant covers the entire skin and is more abundant in the folds of the body (elbow, axillary, inguinal, etc. folds).

Development of internal genital organs continues: in boys - the scrotum, in girls - the ovaries.

Respiratory frequency increases up to 50-60 times per minute.

The swallowing reflex is still well developed: the child constantly swallows amniotic fluid with particles of protective skin lubricant. The liquid part of the amniotic fluid is absorbed into the blood, leaving a thick green-black substance (meconium) in the intestines. Normally, the bowel should not have a bowel movement until the baby is born. Sometimes swallowing water causes hiccups in the fetus; a woman can feel it in the form of rhythmic movements for several minutes.

Twenty-fourth week (162-168 days)

By the end of this week, the weight of the fetus increases to 600 grams, body length to 30-32 cm.

The movements are becoming stronger and clearer. The fetus takes up almost all the space in the uterus, but can still change position and turn over. Muscles grow rapidly.

By the end of the sixth month, the child has well-developed sense organs. Vision begins to function. If a bright light hits a woman’s belly, the fetus begins to turn away and closes her eyelids tightly. Hearing is well developed. The fetus determines pleasant and unpleasant sounds for itself and reacts to them differently. When hearing pleasant sounds, the child behaves calmly, his movements become calm and measured. When unpleasant sounds occur, it begins to freeze or, conversely, moves very actively.

An emotional connection is established between mother and child. If a woman experiences negative emotions (fear, anxiety, melancholy), the child begins to experience similar feelings.

Fetal development in the seventh obstetric month (25-28 weeks)

Twenty-fifth week (169-175 days)

The length of the fetus is 30-34 cm, body weight increases to 650-700 grams. The skin becomes elastic, the number and severity of folds decreases due to the accumulation of subcutaneous fatty tissue. The skin remains thin with a large number of capillaries, giving it a red color.

The face has a familiar appearance to a person: eyes, eyelids, eyebrows, eyelashes, cheeks, ears are well defined. The cartilage of the ears remains thin and soft, their bends and curls are not fully formed.

Bone marrow develops intensively, which takes on the main role in hematopoiesis. The strengthening of the fetal bones continues.

Important processes occur in lung maturation: small elements of lung tissue (alveoli) are formed. Before the baby is born, they are without air and resemble deflated balloons, which straighten out only after the first cry of the newborn. From week 25, the alveoli begin to produce a special substance (surfactant) necessary to maintain their shape.

Twenty-sixth week (176-182 days)

The length of the fruit is about 35 cm, the weight increases to 750-760 grams. The growth of muscle tissue and subcutaneous fat continues. Bones are strengthened and permanent teeth continue to develop.

The formation of the genital organs continues. In boys, the testicles begin to descend into the scrotum (the process lasts 3-4 weeks). In girls, the formation of the external genitalia and vagina is completed.

Improved sense organs. The child develops a sense of smell (smell).

Twenty-seventh week (183-189 days)

Weight increases to 850 grams, body length - up to 37 cm.

The organs of the endocrine system are actively functioning, in particular the pancreas, pituitary gland and thyroid gland.

The fruit is quite active, makes freely various movements inside the uterus.

From the twenty-seventh week in the child individual metabolism begins to form.

Twenty-eighth week (190-196 days)

The child’s weight increases to 950 grams, body length – 38 cm.

By this age the fetus becomes practically viable. In the absence of organ pathology, a child with good care and treatment can survive.

Subcutaneous fat continues to accumulate. The skin is still red in color, the vellus hair begins to gradually fall out, remaining only on the back and shoulders. Eyebrows, eyelashes, and hair on the head become darker. The child begins to open his eyes frequently. The cartilage of the nose and ears remains soft. The nails do not yet reach the edge of the nail phalanx.

This week starts more one of the cerebral hemispheres is actively functioning. If the right hemisphere becomes active, then the child becomes left-handed; if the left hemisphere becomes active, then right-handedness develops.

Fetal development in the eighth month (29-32 weeks)

Twenty-ninth week (197-203 days)

The weight of the fetus is about 1200 grams, the height increases to 39 cm.

The baby has already grown enough and takes up almost all the space in the uterus. Movements become less chaotic. The movements manifest themselves in the form of periodic kicks with the legs and arms. The fetus begins to take a definite position in the uterus: head or buttocks down.

All organ systems continue to improve. The kidneys already secrete up to 500 ml of urine per day. The load on the cardiovascular system increases. The blood circulation of the fetus is still significantly different from the blood circulation of the newborn.

Thirtieth week (204-210 days)

Body weight increases to 1300-1350 grams, height remains approximately the same - about 38-39 cm.

Subcutaneous fat tissue constantly accumulates, skin folds straighten out. The child adapts to the lack of space and takes a certain position: curls up, arms and legs crossed. The skin still has a bright color, the amount of grease and vellus hair decreases.

Alveolar development and surfactant production continues. The lungs prepare for the birth of the baby and the start of breathing.

Brain development continues brain, the number of convolutions and the area of ​​the cortex increases.

Thirty-first week (211-217 days)

The child's weight is about 1500-1700 grams, height increases to 40 cm.

Your child's sleep and wake patterns change. Sleep still takes a long time, during which time there is no motor activity of the fetus. While awake, the child actively moves and pushes.

Fully formed eyes. During sleep, the child closes his eyes, while awake, the eyes are open, and the child blinks periodically. The color of the iris is the same for all children (blue), then after birth it begins to change. The fetus reacts to bright light by constricting or dilating the pupil.

Brain size increases. Now its volume is about 25% of the volume of the adult brain.

Thirty-second week (218-224 days)

The child's height is about 42 cm, weight - 1700-1800 grams.

Accumulation of subcutaneous fat continues, due to which the skin becomes lighter, there are practically no folds left on it.

Internal organs are improved: organs of the endocrine system intensively secrete hormones, surfactant accumulates in the lungs.

The fetus produces a special hormone, which promotes the formation of estrogen in the mother’s body, as a result, the mammary glands begin to prepare for milk production.

Fetal development in the ninth month (33-36 weeks)

Thirty-third week (225-231 days)

The weight of the fetus increases to 1900-2000 grams, the height is about 43-44 cm.

Skin becomes increasingly lighter and smoother, the layer of fatty tissue increases. The vellus hair is increasingly wiped off, and the layer of protective lubricant, on the contrary, increases. Nails grow to the edge of the nail phalanx.

The baby becomes increasingly cramped in the uterine cavity, so his movements become more rare, but strong. The position of the fetus is fixed (head or buttocks down), the likelihood that the child will turn over after this period is extremely small.

The functioning of internal organs is becoming more and more improved: the mass of the heart increases, the formation of the alveoli is almost complete, the tone of the blood vessels increases, the brain is fully formed.

Thirty-fourth week (232-238 days)

The child's weight ranges from 2000 to 2500 grams, height is about 44-45 cm.

The baby now occupies a stable position in the uterus. The bones of the skull are soft and mobile thanks to the fontanelles, which can close only a few months after birth.

Head hair grows rapidly and take on a certain color. However, hair color may change after childbirth.

Intensive strengthening of bones is noted, in connection with this, the fetus begins to take calcium from the mother’s body (the woman may notice the appearance of cramps at this time).

The child constantly swallows amniotic fluid, thereby stimulating the gastrointestinal tract and the functioning of the kidneys, which produce at least 600 ml of clear urine per day.

Thirty-fifth week (239-245 days)

Every day the child gains 25-35 grams. Weight during this period can vary greatly and by the end of the week it is 2200-2700 grams. Height increases to 46 cm.

All internal organs of the child continue to improve, preparing the body for the upcoming extrauterine existence.

Fatty tissue is intensively deposited, the child becomes more well-fed. The amount of vellus hair is greatly reduced. The nails have already reached the tips of the nail phalanges.

A sufficient amount of meconium has already accumulated in the fetal intestines, which normally should go away 6-7 hours after birth.

Thirty-sixth week (246-252 days)

The weight of a child varies greatly and can range from 2000 to 3000 grams, height - within 46-48 cm

The fetus already has well-developed subcutaneous fatty tissue, skin color becomes lighter, wrinkles and folds disappear completely.

The baby occupies a certain position in the uterus: more often he lies upside down (less often, with his legs or buttocks, in some cases, transversely), his head is bent, his chin is pressed to his chest, his arms and legs are pressed to his body.

Skull bones, unlike other bones, remain soft, with cracks (fontanelles), which will allow the baby's head to be more pliable when passing through the birth canal.

All organs and systems are fully developed for the existence of a child outside the womb.

Fetal development in the tenth obstetric month

Thirty-seventh week (254-259 days)

The child's height increases to 48-49 cm, weight can fluctuate significantly. The skin has become lighter and thicker, the fat layer increases every day by 14-15 grams per day.

Cartilages of the nose and ears become denser and more elastic.

Fully lungs are formed and mature, the alveoli contain the necessary amount of surfactant for the newborn to breathe.

The digestive system has matured: Contractions occur in the stomach and intestines to push food through (peristalsis).

Thirty-eighth week (260-266 days)

A child's weight and height vary greatly.

The fetus is fully mature and ready to be born. Externally, the child looks like a full-term newborn. The skin is light, the fatty tissue is sufficiently developed, and vellus hair is practically absent.

Thirty-ninth week (267-273 days)

Typically two weeks before birth the fruit begins to descend, pressing against the pelvic bones. The child has already reached full maturity. The placenta begins to gradually age and its metabolic processes deteriorate.

The weight of the fetus increases significantly (30-35 grams per day). The proportions of the body change completely: the chest and shoulder girdle are well developed, the belly is round, and the limbs are long.

Well developed sense organs: the child catches all sounds, sees bright colors, can focus his vision, and taste buds are developed.

Fortieth week (274-280 days)

All indicators of fetal development correspond to new to the awaited one. The baby is completely ready for birth. The weight can vary significantly: from 250 to 4000 and above grams.

The uterus begins to periodically contract(), which is manifested by aching pain in the lower abdomen. The cervix opens slightly, and the fetal head is pressed closer to the pelvic cavity.

The skull bones are still soft and pliable, which allows the baby’s head to change shape and pass the birth canal more easily.

Fetal development by week of pregnancy - Video

Already from the eighth day, the fetus can be called a baby, it is no longer just a “foreign body”, on the contrary, now the mother’s body will be completely reorganized to create the best conditions for bearing a baby.

Why is 2 weeks of pregnancy a different time for an obstetrician and for an expectant mother?

From a medical point of view, 2 weeks is the period when the last menstruation ends and ovulation occurs. There is no delay yet; the pregnancy itself is hidden. In the second week, the expected period of menstruation begins. It is then that a delay occurs and the woman begins to suspect her “special” situation.

Many expectant mothers begin to worry about the question of what the fetus looks like? Two weeks is the age when the unborn baby is a lump of cells. Often during this period a miscarriage can occur, which the woman may not even know about. Spontaneous termination of pregnancy may look like normal discharge during menstruation. Sometimes women begin to count the age of the unborn child starting from the delay. However, this is already the sixth obstetric week, and during this period the baby’s heart has already formed.

Pregnancy test

It is still quite difficult to determine 100% pregnancy in the second week, since the hCG level is still very low, and the presence of a child can only be shown by a test with a sensitivity of 10 units. A more reliable way to establish pregnancy is ultrasound. The study will not only confirm the presence of a child, but will also show what the embryo looks like: 2 weeks is still too short a period, but at this moment intrauterine life is already beginning to be felt.

The future child immediately after conception

In the second week, the embryo no longer draws nutrition from the egg, but receives nutrients from what the uterus gives it. Fetal development in the second week begins with the formation of the primary intestine tube for digesting food. After two weeks, the embryo looks like a group of cells, but the main characteristics are already contained in the 46 chromosomes that it received from its mother and father.

During these days, the heart and blood vessels are formed. By the 14th day of pregnancy, the baby's primary intestine becomes longer and is divided into two parts. An amniotic sac filled with amniotic fluid forms around the embryo, which will serve as a protective membrane until the end of pregnancy.

The baby's placenta begins to form, connecting the baby to the umbilical cord - this is what the embryo begins to look like 2 weeks after conception. The placenta is an important organ through which the baby communicates with its mother for 40 weeks. Through the umbilical cord, the baby receives useful microelements, water and oxygen. On the contrary, all unnecessary products are eliminated through the placenta by the mother's body. The baby makes its presence known by the end of the second week through placental hormones, which cause a delay in menstruation. After two weeks, the fetus looks like an egg in which the germinal disc has formed.

The egg transforms into an embryo: 2 weeks is the period when the growth of the unborn baby is already 2.5 mm.

At the 2nd week of pregnancy, a baby is actively developing, its cells are dividing, and it gradually descends into the uterine cavity. After two weeks, the fetus looks like an embryo, consisting of two bladders, one of which gives rise to the baby (endothermal), and the other - the placenta and amniotic membrane (amniotic). Fetal development in the second week occurs in the graafian vesicle. By the end of this period, the vesicle will increase in size and protrude above the ovary.

Mother's feelings at the beginning of pregnancy

In the first months of pregnancy, a woman may feel toxicosis more acutely. This is due to the fact that such communication is still being established, and the mother’s body is adapting to a new way of life. Toxicosis can manifest itself in nausea and vomiting, intestinal disorders and other symptoms. The presence of such phenomena is more the norm than a deviation, so you should not rush to see a doctor. At 2 weeks, you can notice other signs of the existence of an embryo:

• increased breast sensitivity;
• discomfort in the form of nagging pain in the lower abdomen;
• increased appetite;
• emotional instability;
• positive pregnancy test.

At the beginning of pregnancy, a woman may feel the urge to apply something warm to the lower abdomen to relieve the feeling of heaviness, but it is important to remember that heating is contraindicated, especially in this area, as it can cause bleeding. The expectant mother should avoid visiting the bathhouse, lifting weights and unnecessary physical activity.

Some experts advise expectant mothers to have their teeth treated during this period. If you do not do this in the second week, you will have to postpone it until the second trimester of pregnancy.

The expectant mother must completely stop smoking and drinking alcohol throughout the entire period of pregnancy. In the second week, you can add a vitamin complex with a high concentration of folic acid (or vitamin B9) to your diet.

If possible, you should limit your visits to places where you can “catch” an infectious disease. It is also advisable to limit the consumption of foods that stimulate the nervous system - coffee, tea, chocolate and processed foods. The expectant mother should not take medications, only in consultation with the doctor if necessary.

Why does a pregnant woman feel drowsy? The expectant mother may complain of fatigue or drowsiness, but this only indicates how harmoniously the development of the fetus occurs: 2 weeks is the period when the formation of the most important organs of the future baby occurs, which requires increased work of the mother’s body.

During the first two weeks, the woman does not yet focus on the delay, and the baby is already firmly established in the uterus and is developing harmoniously. Externally, pregnancy is not yet noticeable, but changes in female hormones have already occurred.

The 3rd week of pregnancy has arrived. What new will appear these days in a woman’s life? What joys and anxieties are associated with this time? The most important points, information and advice - everything for expectant mothers.

Two views on the deadline

For convenience, any doctor will count from the first day of a woman’s last menstruation. The concept of obstetric term is based on this system. According to another system (embryonic), the period is calculated from the middle of the cycle. It is at this time that ovulation and conception most often occur.

In obstetric practice, the third week is the period of fertilization. The egg has matured and is moving towards the uterine cavity. At some point, a sperm penetrates into it, and then the zygote will continue to move. This new cell has a full set of chromosomes and is capable of dividing very quickly.

According to the embryonic method, once a single cell is already developing vigorous activity and actively living its special, hidden life. What about the expectant mother? If she doesn’t yet know exactly about her pregnancy, she probably guesses. After all, her period is already about a week late.

To avoid getting confused in the lines , (terms of pregnancy: obstetric and embryonic).

From guesswork to certainty

Three weeks after conception, a pharmacy test will show those same two stripes. At the same time, the level of the hCG hormone in the woman’s body will increase. An appropriate blood test will confirm pregnancy. But if we talk about the obstetric third week, pregnancy has barely begun and is not yet determined. Moreover, a woman can still get her period.

According to medical research, 70-75% of fertilized eggs are rejected by the female body even before fixation in the uterine cavity. This happens for many reasons:

• initial cellular defects;
• hormonal disorders;
• infectious diseases;
• stress.

Sometimes rejection occurs without any prerequisites at all. Since the embryo has not actually begun to develop, this phenomenon is not considered a miscarriage. The woman may, in principle, not know what happened. For her, one day the next menstruation will simply come.

The third week from conception is the time to make a decision if pregnancy was not only not planned, but also not allowed. Anything can happen in life. In fact, no method of contraception is 100% guaranteed. And sometimes partners treat this important issue carelessly.

In any case, if you terminate an unwanted pregnancy, then now. Only the decision to have an abortion must be balanced and accepted with full responsibility. Any actions must take place according to the instructions and under the supervision of a physician. “Amateur action” here can lead to the most unfavorable consequences.

Feelings of the expectant mother

In the third obstetric week, everything goes as usual for a woman. But three weeks after conception there can be a lot of new experiences.

For example, a woman begins to accurately recognize dark and light grapes by smell. Even if before she could not boast of a keen sense of smell at all. And then she begins to be incredibly irritated by the smell of the eau de toilette of her beloved man.

Food tastes may also change. Sauerkraut or cucumbers become perhaps the most delicious foods, and your favorite type of cheese suddenly causes disgust. Perhaps this is a prelude to taste quirks. Among future and established fathers, there are whole legends about wives who ate herring with sour cream or demanded strawberries in February.

And the most active and lively woman suddenly turns into a “sleeping beauty.” It seems like you have complete rest and no overwork. But at the same time, more than anything else, I want to fall asleep.

All such sensations arise in a woman due to hormonal and physical changes. The body is intensely tuned to work in a special mode. The expectant mother may also note:

• increased breast sensitivity, especially nipples;
• frequent visits to the toilet due to relaxation of the smooth muscles of the intestines and increased activity of the ureters;
• periodic constipation;
• nausea (which may result in vomiting).

What will others notice?

Objective signs are absent in the third obstetric week, but can be very noticeable with an embryonic approach. The test or blood test has probably been done and confirmation has been received. Thoughts about the baby can significantly affect the appearance of the expectant mother. She becomes more feminine, graceful and seems to blossom.

However, at the same time, a woman can suddenly suddenly “break down” and become irritated. Relatives or loved ones will see a noticeable increase or decrease in appetite.

During a medical examination, the doctor will note specific symptoms: breast swelling and an increase in the size of the patient’s uterus.

Embryo or fetus? What's going on inside?

From an obstetric point of view, in the third week a full-fledged pregnancy has not yet occurred. For now, the uterus is preparing to receive a fertilized egg.

If the embryo has not yet implanted in the uterine cavity, now this will definitely happen. The whole process is quite complex, it takes about forty hours. First of all, the embryo produces a particularly important immunopressor protein. The fact is that half of the embryo’s cells are foreign to the mother’s body - after all, they “came” from the child’s father. Without a special protein “signal” the uterus will never accept the future fetus - the immune system will not allow it.

The fixation of the embryo in the uterus gives rise to another important process. This placentation. Through it, the fetus in the womb receives all the necessary nutrients.

What does the future child look like? So far everything is quite prosaic. The embryo is in the morula stage - a dense round lump of cells. The morula quickly turns into a blastocyst. This means that a cavity with fetal fluid is formed inside the lump, in which the baby will then develop.

The size of the fetus (embryo) is negligible. By the end of the third week after conception, it has a diameter of 0.1-0.2 mm, and its weight is 2-3 micrograms (mcg, one thousandth of a gram). And in this tiny grain of sand there are already about 250 living cells. Very soon the formation and development of the main systems of the fetal body will begin, and the tiny heart will count its first beats.

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The term seems to speak for itself. Theoretically, in addition to the uterus, a fertilized egg can implant in other areas of the female reproductive system (for example, on the ovary or in the fallopian tube).

The percentage of ectopic pregnancies is very small, but the sad possibility always exists. When to suspect something is wrong? Severe growing pain is the first signal of possible problems. In this case, the stomach hurts not from below, but from the left or right. This is usually the site where the embryo is not implanted properly. The pain intensifies when the doctor palpates. The most experienced specialists can even determine the location of implantation.

Nowadays, gentle methods have been developed to get rid of ectopic pregnancy. They do not give negative consequences and do not interfere with motherhood in the future.

Spontaneous termination of pregnancy

Miscarriage is the rejection of a fetus already implanted in the uterine cavity.. It can be triggered by many factors. The main signs are bleeding or constant spotting, sharp pain and pulling sensations in the lower abdomen and lower back. The consequences depend on how quickly the woman herself and the doctors reacted.

It is important for the expectant mother to remember that mild pain is common in the early stages of pregnancy. The same hormonal changes are to blame. The body adapts to the new state, and the lower back and lower abdomen “respond” to this.

During pregnancy, 3 weeks from the moment of conception, freezing sometimes occurs. Then the test (both pharmacy and hCG) first confirms the pregnancy, and then seems to “no longer see” it. However, my period does not come. Detection of a frozen pregnancy requires a careful approach and thorough diagnosis.

Is it necessary to do an ultrasound?

In a normal pregnancy, an ultrasound in the third obstetric week may be required to confirm that ovulation has occurred. Three weeks after conception, a scan during a normal pregnancy will be practically uninformative. The embryo will look like a small dot against the background of the uterine cavity.

But if an ectopic pregnancy is suspected, it is based on the results of the ultrasound that the place of attachment of the embryo will become clear and a decision will be made on further actions. For greater reliability, ultrasound can be performed transvaginally, that is, through the vagina. The procedure is carried out carefully, carefully and does not cause discomfort.

Will there be any discharge?

During the third week of pregnancy, any special discharge is not typical. During an obstetric count, relatively thick and dense mucus may be released. It protects the egg from external infections - what if conception happens or has it already happened?

Strong mucous discharge, especially with an unpleasant odor, can be a signal of illness. It's better to check with a doctor.

As the fetus implants, minor implantation bleeding may occur. This is just a faint brown discharge or pink or bloody smears.

If you are in the third week of conception, the pregnancy is confirmed, and suddenly blood starts to flow, this may mean a miscarriage.

Body temperature: the line between normal and disease

If the embryonic period is three weeks, a slight increase in temperature (37.2 ° C) without signs of a cold is normal. However, 37.5 or more is already a danger signal.

When visiting a doctor, a woman must warn him about a possible or confirmed pregnancy. The doctor will take this into account when choosing treatment methods.

For many people, a cold is a mild illness that can be treated on their own. Including antibiotics. This is 100% unacceptable for a pregnant woman. Antibiotics, even topical ones, should only be prescribed by a doctor. And he can do this only in the most extreme and severe cases. Side effects of this group of drugs can cause many different complications in the embryo.

3 weeks pregnant and sex

The third obstetric week will not be complete without sex. When planning to conceive, a couple's intimate life usually follows a certain schedule. Ideally, sex should take place on the day of ovulation, 2-3 days before and 2-3 days after it. This improves the quality of sperm and increases the likelihood of conception.

In the third week after conception, the sex life of future parents may remain the same or change. Some women experience increased attraction to the father of the child. Others note a decrease in libido. Both are normal and should not be a cause for concern.

There is also a rather rare sign of pregnancy that almost never occurs. After sexual intercourse, a woman may feel a sharp, severe pain in the vagina and labia. In this case, intimate life gives the expectant mother discomfort, even a feeling of fear. Fortunately, such feelings soon pass.

If the intimate life of future parents threatens to deteriorate, it is important to take action in time. The main thing at this time is trust between a woman and her husband (partner). It is imperative to explain to a man that changes in desire happen, that he remains a loved and desired person. The future father will need patience and attention to his significant other.

Intimate life will have to be stopped completely if there is a threat of miscarriage.

Nutrition for the expectant mother

1. Meals are small, 4-5 times a day.
2. For the full presence of protein, you need lean meat and, on the contrary, fatty fish (it contains important acids), as well as legumes and dairy products. Mushrooms are also a protein, but such food can be hard on the stomach.
3. Fresh vegetables and fruits - to provide vitamins and microelements. No pharmaceutical vitamin complex will be truly effective if the mother does not receive natural vitamins from food.
4. No colorful sodas! This is zero benefit and a lot of calories.
5. It is advisable to abandon white buns and switch to coarse bread.

Another nutritional recommendation will help expectant mothers with early toxicosis. An attack of nausea can occur anywhere: at work, while walking, on public transport. Sometimes it “rolls over” so much that a woman’s strength literally leaves her. In addition, vomiting in public places is a strong psychological stress. What to do?

It is advisable to experimentally find that “yummy” that will help suppress an attack of nausea. It could be anything. A bottle of carbonated mineral water will help if stomach acidity increases during nausea. Someone carries an apple with them in a plastic bag and bites off little by little when nausea sets in. A piece of cheese, a cracker or something else may help - the expectant mother needs to experiment carefully.

In case of sudden vomiting, it is better to carry a special bag and wet wipes in your purse.

Other “dos” and “don’ts”

An expectant mother can and should take care of herself and her unborn baby. This should be done in all cases: if pregnancy is planned, allowed or has already been detected. The main recommendations are the same as in the first and second weeks:

• Taking vitamins. The doctor must decide which medications are needed.
• If for some reason alcohol and cigarettes are still present in a woman’s life, they need to be “banished” immediately and for a long time. In the third week from conception, any negative factors are dangerous for the embryo.
• Every effort must be made to avoid nervous shock. Only positive emotions. But they should not be excessive. Having experienced some kind of moral uplift, the expectant mother may note with great surprise that she becomes very tired even from positive experiences.
• Do not lift heavy objects or perform difficult physical work. If the expectant mother plays sports, the load will have to be reconsidered, or even change the type of activity. Most often, expectant mothers are recommended swimming (for their own pleasure) and yoga.

In the third week from conception, it is important for the expectant mother to remember: she is now not alone and shares everything that happens to her with her baby. Paying attention to yourself will make the third week of waiting joyful and happy.

The second week of pregnancy is not much different from the first. The release of the egg may be accompanied by a sensation of nagging pain on one side of the abdomen, and pinkish discharge is possible. Conception has not yet occurred, so the fetus has not yet formed. The ultrasound photo does not show anything yet; the woman’s weight does not change.

Conception has not yet occurred, so the fetus has not yet formed. The ultrasound photo does not show anything yet; the woman’s weight does not change.

In order for fertilization to be successful and pregnancy to occur, it is better to abstain from sexual relations a few days before ovulation - there will be more active sperm. Before sexual intercourse, a woman should not be overzealous with the intimate toilet - a change in the vaginal environment (due to the influence of soap or gel) can reduce the activity of fertilizing cells.

In the second week, it is also too early to talk about pregnancy, but during this period important changes occur in a woman’s body, preparing it for conception. In the second week, changes continue in the ovaries and uterus, which are necessary for pregnancy to occur. The process of ovulation occurs in the ovaries. During the ovulation cycle, about 20 follicles mature in a woman’s ovary, but only one of them will become a mature egg. One of the follicles approaches the already thinned wall of the ovary, bursts and exits into the fallopian tube as a mature egg. The moment of release is called ovulation.

Ovulation is a phenomenon that represents the release of an egg from the ovary into the fallopian tube as a result of the rupture of a mature follicle. During ovulation, the egg is in the second-order oocyte maturation stage.

Ovulation usually occurs on the 14th day of the menstrual cycle, but depending on the length of the cycle it can shift. A mature egg remains in the fallopian tube for no more than a day, slowly moving towards the uterine cavity. Fertilization occurs here, in the fallopian tube, where sperm penetrate through the vagina and uterine cavity.

Sperm, unlike eggs, remain viable for 72 hours. Thus, conception of a child can occur a few days after sexual intercourse. However, ovulation still remains the most favorable moment for conception. Well, it’s worth adding that depending on which sperm makes its way to the egg, the sex of the child is formed and its external characteristics are determined. Simultaneously with the changes in the ovary, the uterus begins to prepare for the implantation of a fertilized egg. The mucous layer of the uterus loosens and thickens. All this happens under the strict control of hormones produced by the ovaries.

At the moment of conception, there is a danger of disruption of fetal formation. At this time, both parents need to stop drinking alcohol and taking medications (except vitamins), smoking, and contact with household chemicals. Everyone knows about it.

Feel

The sensations in the second week of pregnancy are practically no different from those in the first. Very often, a woman is not even aware of a very interesting situation, therefore, when a spontaneous miscarriage occurs at this time, accompanied by atypical brownish bleeding, abundant and prolonged, the woman mistakes these signs for normal menstruation and does not even realize that she was pregnant.

Signs of pregnancy at this stage are weakly expressed, but if a woman planned this pregnancy, most often she already guesses. Signs of pregnancy are caused by fairly high levels of hormones that are necessary to preserve the unborn fetus. In the second week, a woman may complain of discomfort in the lower abdomen, slight malaise, drowsiness, she becomes nervous, her mood often changes, her appetite may increase somewhat, and sometimes unexpectedly change to the point of wanting to eat something inedible, an aversion to food may appear. some odors (smells of perfume, tobacco smoke). There is also a feeling of engorgement of the mammary glands. Most often, the pregnancy test is positive.

In addition, during this period, a woman’s libido increases and mucous discharge appears, which indicates the process of ovulation.

Fetus and belly size in the second week

Conception has not yet occurred, so the fetus has not yet formed. Nothing can be seen on the ultrasound yet. A woman’s weight may increase, but this is not yet at all related to the growth and development of the fetus, but is usually due to the increased appetite of the expectant mother, so she should carefully monitor her diet so as not to gain extra pounds ahead of time.

Dangers

The onset of pregnancy should be clearly associated in a woman with a healthy lifestyle, because now she is responsible not only for herself, but also for the small organism growing inside her. Therefore, it is strongly recommended to give up all bad habits, such as smoking, both active and passive, and drinking alcohol in any quantity. This is recommended to be done before pregnancy for both women and men. During this period, visiting the bathhouse is undesirable; lifting weights and performing heavy physical activity is prohibited. Many pregnant women complain of poor sleep, increased excitability and other ailments and therefore self-prescribe sleeping pills and sedatives. This is unacceptable in principle, and even more so during pregnancy. If something worries you, you must first consult your doctor and strictly follow his recommendations.

Stomach ache

Some women experience pain in the lower abdomen during this period. Most often, this is the result of natural processes occurring in a woman’s body, and more specifically the process of ovulation, pain appears due to irritation of the ovary by the fluid of a burst follicle. Often, to reduce pain, women apply a warm heating pad, but this should never be done, because the heat causes the blood vessels to dilate, which can cause internal bleeding.

It is important that if a woman is bothered by severe, prolonged abdominal pain at this stage, she should consult a specialist.

Mom's nutrition

It's no secret that the importance of nutritious and proper nutrition for an expectant mother is enormous.

Even in such a short period of time, you need to carefully consider your diet. A pregnant woman must receive sufficient amounts of vitamins and minerals, such as calcium, magnesium, iron, iodine, folic acid and others. It has been noticed that pregnant women begin to feel the need for one dish, and the sight of another dish that they previously loved makes them feel nauseous. When planning a diet for a pregnant woman, you should adhere to the following simple rules:

• Food should be varied.
• To avoid unwanted excess weight, you should try to eat low-calorie foods.
• Undoubtedly, a significant part of the diet should be fresh vegetables and fruits.
• It is advisable to exclude spicy and salty foods from the diet.
• Try to avoid legumes, which can cause bloating.
• Give preference to boiled and steamed dishes.
• Be sure to include milk and dairy products in your diet.

Many women are accustomed to drinking coffee in the morning; during pregnancy they will have to give up this habit, since the caffeine contained in natural coffee increases blood pressure. For the same reason, you should give up strong tea, which dilates the blood vessels of the brain and heart.

What do we have to do

Usually, at such a time, a woman does not yet know about her pregnancy, so she does not take special measures. However, if suddenly a woman becomes aware of her “interesting situation,” she should register with the antenatal clinic and begin an examination with other specialists: be examined by a therapist, cardiologist, endocrinologist, ophthalmologist, nephrologist. Of course, if you know about your chronic diseases, you can purposefully go to the right specialist to get the necessary recommendations and thereby protect yourself and your future baby from unpleasant consequences. If you do not know about the existence of any diseases or infections, then get examined for preventive purposes. In any case, consultation with specialists of another profile will not be superfluous, because during pregnancy, all systems and organs of a woman are tested for strength.

And, of course, it’s worth talking about the daily routine. In principle, it can remain the same as it was before pregnancy, but a pregnant woman should be exempt from night work and heavy physical labor, as well as any other work that may harm her health and the health of the unborn child. A healthy full sleep is necessary, walking in the fresh air and dosed physical activity are useful. Try to avoid stressful situations.

What does the belly look like?

In the second week of pregnancy, the belly remains virtually unchanged in size. The photo shows that there are no major changes.

Belly photo

Pregnancy is the process in which a baby develops from two tiny parent cells. The development of the fetus by week of pregnancy is a fascinating story about what exactly happens in each week of pregnancy, how the weight and height of the fetus changes, what sensations arise in the mother as the pregnancy lengthens. In the article we will tell you about what interests every expectant mother: when the baby begins to hear her speech, when and how the weight of the fetus changes, when you can take a photo of the fetus with an ultrasound, what causes the mother’s feelings during pregnancy, and much more.

First and second weeks of pregnancy: baby? Which child?

At the moment the embryo appears, the pregnancy period is already 2 weeks. Why? Let's decide from what we will calculate the period. There are concepts of embryonic and obstetric term. The embryonic period of pregnancy is the true period from the moment of conception. Obstetric period – from the first day of the last menstruation. The obstetric period is on average 2 weeks longer than the embryonic period. During an ultrasound, the pregnant woman’s chart and sick leave will always indicate the obstetric period according to the date of the last menstruation. But from the third week of pregnancy, the development of the fetus actually begins. Below you will find a description of each week of pregnancy: how the fetus develops, what happens to the uterus, how the expectant mother’s sensations change.

3rd week of pregnancy: parents meeting

At the end of the second and beginning of the third week (on average on the 14th day of the cycle), ovulation occurs. At this moment, the woman’s egg leaves the ovary into the fallopian tube and where it meets the sperm in the next 24 hours. Of the 75-900 million sperm that enter the vagina, less than a thousand reach the cervical canal. And only one will penetrate the egg.

The sperm and egg carry half the set of chromosomes of the future person. As a result of their fusion, the first cell of a new organism with a full set of chromosomes is formed - a zygote. Chromosomes determine the baby's gender, eye color, and even character. The zygote begins to divide and move towards the uterine cavity. The journey to the uterus will take approximately 5 days, by which time the embryo will consist of approximately 100 cells. The next stage is implantation - the introduction of the embryo into the wall of the uterus.

4th week of pregnancy

The ball of cells is officially called an embryo. The size of the fruit at this stage is like a poppy seed, approximately 1.5 mm.

At the end of this week, the expectant mother notices that the expected menstruation does not begin. At this time, a woman may feel drowsiness, weakness, increased sensitivity of the mammary glands, and mood swings. A pregnancy test shows a positive result. The test detects the hCG hormone, which begins to be produced after implantation.

The embryonic period lasts up to 12 weeks. The axial organs and tissues of the baby are formed. A yolk sac with a supply of nutrients and an amniotic sac are formed; from these extraembryonic organs, the fetal membranes and chorion - the future placenta - subsequently develop. Below we will look at what happens in the embryonic period every week, how the height and weight of the fetus changes and what sensations await the woman.

5th week of pregnancy

The embryo consists of three layers - the outer ectoderm, from which the ears, eyes, inner ear, and connective tissue will be formed; endoderm, from which the intestines, bladder and lungs will develop; and mesoderm is the basis for the cardiovascular system, bones, muscles, kidneys, and reproductive organs.

The anterior and posterior poles of the embryo are determined - the future head and legs. The body of the embryo is laid along the axis of symmetry - the chord. All organs will be symmetrical. Some are paired, for example, kidneys. Others grow from symmetrical buds, such as the heart and liver.

At the 5th week of pregnancy, with a hCG level of 500-1000 IU/l, a fertilized egg can be determined to be 2 mm in size, which is the size of a sesame seed. Each woman experiences this period differently, but most experience nausea, drowsiness, and odor intolerance - signs of toxicosis.

6th week of pregnancy

Now the baby is no larger than a lentil, at the beginning of the week 3 mm, and by the end - 6-7 mm. The embryo is somewhat similar to a fish and still bears little resemblance to a person. The rudiments of arms and legs appear. When the hands appear, the legs will still be in the form of rudiments. The cerebral hemispheres are formed. The small heart is pulsating and is dividing into sections.

The future placenta is formed from chorionic villi, vessels actively grow through which blood is exchanged, and accordingly everything necessary for the unborn child between mother and baby.

At this time, toxicosis may intensify, and severe weakness and vomiting may appear. Drinking enough fluids is important during these weeks of pregnancy.

7th week of pregnancy

The embryo is approximately the size of a blueberry, height 8-11 mm, weight up to 1 g. Hints of the future nose, eyes, ears and mouth appear. There is a fantastic rate of brain growth - 100,000 cells per minute! Interdigital spaces have already appeared on the handles, but the fingers are not yet separated. The umbilical cord and the uteroplacental circulatory system are formed: the baby’s breathing and nutrition comes from the mother’s blood.

It is during this period that many expectant mothers often come for their first ultrasound scan during pregnancy. At 7-8 weeks, the CTE (coccygeal-parietal size) is 10-15 mm. An ultrasound detects a heartbeat with a frequency of 100 to 190 beats per minute, which is significantly higher than that of an adult. At this time, the first photo of the gallery of fetal development is taken week by week. Without a doctor's instructions, you won't know where to look. It will be clearer later, especially on a 3D ultrasound.

While the mother has not yet noticed an enlarged abdomen, the gynecologist can already tell about an enlarged uterus. The woman experiences increased urination, which is associated with an increase in the volume of fluid in the body.

8th week of pregnancy

The baby is the size of a bean, from 15 to 40 mm, and weighs approximately 5 grams. Over the past two weeks it has grown 4 times! The contours of the face continue to develop, they become more graceful, the upper lip and tip of the nose stand out, and the formation of the eyelids begins.

At the 8th week of pregnancy, ossification of bones begins - arms, legs, skull. The structuring of the gastrointestinal tract, heart, kidneys, and bladder is completed.

Around 7-8 weeks of pregnancy, the baby begins to move, but the mother will not feel these movements in the coming months. Mom’s condition remains virtually unchanged. It may become easier due to adaptation to the condition and awareness of your new role.

9th week of pregnancy

The little man is only the size of a grape - its length is 35-45 mm, and its weight reaches 10 grams. The formation of the reproductive system occurs, and the adrenal glands are already producing hormones, including adrenaline.

The brain is rapidly developing, including the cerebellum, which is responsible for coordinating movements. Movements become more controlled. The digestive system is actively developing. The liver begins to produce new blood cells. The head occupies half the entire length of the body. Tiny fingers are getting longer.

The amount of circulating fetal DNA in the mother's blood is sufficient to perform a non-invasive prenatal test.

The mother still has signs of toxicosis. Usually at this time she turns to a gynecologist to register.

10th week of pregnancy

Do you know this fruit - kumquat? This is approximately the size of the baby now. This week it will officially be called a fetus, but for now we call it an embryo. This period is considered the end of the first critical period. Now the dangerous effect of drugs leading to developmental defects is not so significant.

A lot of events are happening these days. The webbing between the fingers disappears and the fingers separate. The bones harden. The kidneys begin to work, performing their main function - producing urine. The brain produces 250,000 neurons every minute. A diaphragm is formed between the abdominal and thoracic cavities.

My mother is experiencing symptoms of toxicosis. Due to changes in nutrition, metabolism, muscle tone and hormonal fluctuations, your figure and body movements may change. The uterus is the size of a grapefruit, but the pregnancy is not yet noticeable to others.

11th week of pregnancy

From 11 to 13 weeks, the baby undergoes a serious medical examination - ultrasound screening. The thickness of the collar space and nasal bones are determined, a study of blood vessels is carried out, and gross changes in the structure of the body are excluded. They examine the internal organs, facial structure, brain, arms and legs, and spine. Your baby is only the size of a fig, and the doctor describes the anatomy of the fetus in such detail! The head is still large relative to the body, but the proportions continue to change: the head is large, the body is small, the upper limbs are long, and the lower ones are short and bent at the knees. The rudiments of nails and teeth appear.

With the results of the ultrasound, the mother is given a biochemical blood test to check for chromosomal abnormalities and the risk of developing pregnancy complications.

The symptoms of toxicosis are replaced by new sensations: heartburn, bloating, and there may be constipation. A woman should pay more attention to her diet and fluid intake.

12th week of pregnancy

Your baby is about the size of a lime. Until 11-12 weeks, there are no reliable ultrasound differences between boys and girls. The probability of correctly determining the sex of the fetus is already above 50%. The weight of the fruit is about 20 grams, and the length is about 9 cm.

At this stage, the baby begins to actively move his arms and legs, hands, and fingers. Due to active growth, the intestines no longer fit in the tummy and begin to fold into loops. During this period, the intestines are trained: amniotic fluid passes through it, which is swallowed by the fetus. White blood cells appear in the blood - leukocytes, which have the function of protecting against infections.

Mom's weight gain by the 12th week of pregnancy is about 1-2 kg. Doctors recommend doing gymnastics for pregnant women, and swimming is recommended.

13th week of pregnancy

A pea pod is how you can describe the size of a baby in everyday measurements. Or 7-10 cm, 20-30 grams. From the 13th week the second trimester of pregnancy begins. All the main organs and systems have already been formed; the rest of the time before birth, the organs will grow and develop.

The face becomes more and more human-like. The ears move closer and closer to their place from the neck, and the eyes from the side to the center of the face. The first hairs appear. 20 baby teeth have been formed.

The head is still disproportionately large, but the body will now grow faster. The hands continue to grow, the baby can already reach his face. Often, during an ultrasound, doctors show parents how the baby puts his finger in his mouth.

During this period, the shape of the abdomen changes, and the previous clothes become tight. Those around you may notice a woman’s new emotional mood; she becomes calmer and more relaxed.

14th week of pregnancy

At week 14, the fetus grows to 13 cm and 45 grams. In boys, the prostate forms, and in girls, the ovaries descend into the pelvis. The palate is already fully formed, active reflex sucking begins. The baby imitates breathing movements in order to effectively take the first breath after birth.

The formed pancreas begins to produce the most important hormone of carbohydrate metabolism - insulin. And in the depths of the brain, the pituitary gland begins to work - the head of all organs of the endocrine system, it is he who subsequently controls all the glands of the body.

The uterus is located 10-15 cm above the pubis; the woman herself can feel its upper part. It is recommended to use special cosmetics for the skin of the abdomen.

15th week of pregnancy

The fruit is the size of an apple and weighs about 70 grams. The whole baby is covered with small vellus hair - they are on the back, shoulders, ears, and forehead. These hairs help retain heat. Then, when the baby gains enough fatty tissue, the hairs will fall off. The child makes various grimaces, winces, frowns, squints, but this does not reflect his mood at all. He changes his position all the time, actively moving. But the baby is still too small and does not hit the walls of the uterus. A unique skin pattern appears on the fingertips and special proteins appear on the red blood cells that determine the blood type.

Mom may develop pigmentation on her stomach.

16th week of pregnancy

The baby is the size of an avocado. Skeletal bones become harder, but flexible enough for the baby to pass through the birth canal. The umbilical cord contains one vein and two arteries, surrounded by a gelatinous substance that protects the vessels from pinching and makes the umbilical cord slippery for movement. In girls these days, sex cells are formed - your future grandchildren.

Weight gain during this week of pregnancy is 2-3 kg.

17th week of pregnancy

The baby's size is 12-13 cm and weighs up to 150 g, the size of a turnip. The arms and legs are commensurate with the size of the body and head. Fat begins to be deposited under the skin and sweat glands develop. The placenta provides the baby with vitamins, minerals, proteins, fats and oxygen while removing waste products.

Due to an increase in the volume of circulating blood, the mother may experience a rapid heartbeat. In this case, bring this to the attention of your doctor to see if everything is okay.

18th week of pregnancy

Your child is the size of a bell pepper and weighs 250 grams and is ready to communicate. Yes, now the baby can hear, and a loud sound can scare him. He gets used to his parents' voice, and will soon be able to recognize it from other sounds.

The fetal endocrine system is actively developing and functioning. There are so many “baby” hormones that the baby can even supply the mother’s body.

This week, mom may feel fetal movements for the first time. As long as they are mild and infrequent, don't worry if you don't hear your baby too often.

19th week of pregnancy

The height of the fetus is 25 cm, and the weight is already 250-300 grams.

The cheese-like lubricant coats your baby's skin and helps regulate body temperature. The formation of molars occurs; they are located under the rudiments of milk teeth. The head does not grow as quickly, but the limbs and body continue to grow, so the baby becomes more symmetrical.

The uterus is located 1-2 cm below the navel. Due to its intensive growth, painful sensations associated with stretching of the uterine ligaments may occur.

20th week of pregnancy

A happy child weighing 240 grams. At this stage, he is especially good at flexing and extending his arms and legs. He is becoming more and more like his parents.

Week 20 is the equator of pregnancy. The growing uterus compresses the internal organs, so the mother experiences shortness of breath and frequent urination.

During these weeks, the mother attends the next scheduled ultrasound and Doppler measurements are performed. This is a good time for a video ultrasound and regular photos of the heir.

21st week of pregnancy

The height of the fetus is 25 cm, and the weight is 400 g. Most of the nutrients come from the placenta. If amniotic fluid is swallowed, the stomach is already equipped to digest it and receive nutrients. The baby begins to feel the taste.

The mother gains more weight as the baby grows rapidly.

22nd week of pregnancy

By the end of the week the baby will be about 500 grams. The skin is no longer transparent, but remains red and wrinkled and covered with grease. Nerve endings mature and the baby becomes sensitive to touch. From 21 to 25 weeks, the brain increases 5 times - from 20 to 100 grams!

23rd week of pregnancy

Billions of brain cells will develop over the next few weeks. Their job is to monitor all of your baby's movements, senses, and basic life functions such as breathing.

The lungs begin to produce a substance that allows the lungs to inflate and fill with air after birth, and the fetus begins to “breathe.” The frequency of respiratory movements is 50-60 per minute.

The height of the uterine fundus is 4 cm above the navel. The uterus grows, which can cause discomfort in the spine and joints, so a special bandage may be required.

24th week of pregnancy

The baby is still small, his weight is 600 g, and his height is about 33 cm. The child actively reacts when addressed to him. The inner ear is already fully formed (the vestibular apparatus), he began to understand where is up and where is down, movements in the uterine cavity become more meaningful.

Mom gains about 500 grams per week. Swelling of the feet may occur, so it is important to choose comfortable shoes and rest your feet.

25th week of pregnancy

The height of the fetus is 30-32 cm, weight is 750 grams. Meconium forms in the large intestine - the baby's first stool, which will be completely passed within a few days after birth. The osteoarticular system is actively developing, bones are strengthening.

The mother may experience signs of anemia (anemia) developing due to iron deficiency. Fatigue, pallor, fatigue and tachycardia are reasons to consult a therapist and take blood tests for anemia.

26th week of pregnancy

Height 34 cm, weight 900 grams.

The lungs are actively developing, they are filled with a special substance that will not allow the lungs to stick together after the first breath.

The child has clearly defined periods of sleep and wakefulness. Mom feels his activity by movement in her stomach. If you are lucky, your sleep and activity periods will coincide with your baby's.

27th week of pregnancy

The fetal body weight is already about a kilogram, and its height is 34 cm. Growth hormone begins to be produced in the pituitary gland. And the thyroid gland contains hormones that regulate metabolism.

Due to involuntary contractions of the diaphragm, the mother may feel hiccup-like movements of the baby. In adults, such movements are accompanied by the closure of the vocal cords, which is why the characteristic “hiccup” sound occurs, but in a baby before birth, this space is filled with liquid, so this “hiccup” is silent.

New sensations may occur in the legs - tingling, goosebumps or even cramps. This is a reason to consult a doctor for further examination and treatment.

28th week of pregnancy

Now your baby is beginning to close and open his eyes, which until this moment were not completely closed. The iris of the eyes acquired color due to pigment, although this coloring is not final. Children's eye color may change until they are one year old.

At week 28, in case of multiple pregnancy, the mother receives a “sick leave”. The weight gain by this time is 7-9 kg. At this time, Rh-negative mothers are given immunoglobulin.

29th week of pregnancy

The child is 36-37 cm long, weighs approximately 1300 grams and is becoming stronger and more active. We can say that he shows character. A child reacts differently to different foods, sounds, and light.

A woman suffers from heartburn and heaviness after eating. There may be frequent urination or even false urges.

30th pregnancy

In the coming weeks, your baby will actively gain weight. Adipose tissue will perform the function of thermoregulation after birth, provide energy, and protect organs. The baby's movements will become less active, which is associated with an increase in his size. But if you do not feel any shocks as usual, be sure to tell your doctor. Pregnant women may feel breast swelling and notice the release of colostrum.

At this time, a certificate of incapacity for work is issued for a singleton pregnancy.

From 28-30 weeks of pregnancy, regular CTG (cardiotocography) begins to assess the condition of the fetus. CTG evaluates fetal heartbeat, uterine tone and motor activity.

31st week of pregnancy

Before birth, the little man will be in the fetal position, because otherwise he will no longer fit in the uterine cavity, his weight is 1600 g, and his height is already 40 cm.

These days, an important event occurs in male fetuses - the testicles on the way to the scrotum. In girls, the clitoris is almost formed.

Weekly weight gain - 300-400 grams. During these periods, swelling may appear and blood pressure may increase, which can be a symptom of a serious complication - preeclampsia. Therefore, the expectant mother should be as attentive as possible to any changes in well-being.

At 30-32 weeks, an ultrasound of the third trimester is performed with Doppler measurements - assessment of blood flow.

32nd week of pregnancy

This is an important week, another critical deadline has passed. Babies born at this stage are healthy and fully functional. By this week, all major organs are functioning fully, except for the lungs, which need a little more time to fully mature.

The expectant mother may experience pain in the joints and symphysis pubis. These phenomena can be alleviated by wearing a bandage and swimming.

33rd week of pregnancy

It is becoming increasingly difficult for the baby to move; he is already 44 cm and weighs about 2 kg. Many children like to live at their mother's rhythm: sounds, food and walks can influence the child's activity.

The height of the uterine fundus is 34 cm from the level of the pubis. It becomes more difficult for mom to walk or exercise a lot and needs a break.

34th week of pregnancy

Within a few weeks, your boy or girls begin to prepare to meet their parents. The original white lubricant that covers the skin begins to thicken, accumulating in the armpit and groin folds, behind the ears. At the time of the newborn's first toilet, the lubricant will be removed. Height 47 cm, weight 2200-2300 g.

Pregnant women begin to feel false contractions - the muscles are preparing for the birth process.

35th week of pregnancy

The fetus is preparing for birth, finally taking the correct position, upside down. This is the case for approximately 97% of children. The remaining 3% may occupy a position with the pelvis down or even transverse. Fetal height is 47-48 cm, weight is 2300-2500 g.

Almost all expectant mothers experience shortness of breath at this stage.

36th week of pregnancy

The baby continues to store fat, which is vital after birth for energy and heat retention. The sucking muscles are ready to work: after birth, the baby will be hungry and will ask to be fed for the first time.

The height of the uterine fundus is 36 cm. Hormonal changes in the woman’s body begin to prepare for childbirth - prostaglandins are also produced.

37th week of pregnancy

The movements of his fingers become more coordinated, and soon he will be able to grab your finger. The accumulation of subcutaneous fat continues, its volume is approximately 15% of the baby's weight. Height 48-49 cm, weight 2600-2800 g. The vellus hair covering the body gradually disappears.

A pregnant woman feels the harbingers of labor - prolapse of the uterine fundus, a decrease in the volume of the abdomen, loosening of stools, intensification of contractions, and the passage of a mucous plug.

38-40 weeks of pregnancy

In obstetrics textbooks, 38 weeks was the term for full-term pregnancy. If your little one is born right now, it will be a full-term pregnancy, and the baby will not have any of the risk factors associated with being born prematurely. All further events are aimed at preparing for childbirth.

The passage of a mucus plug should be distinguished from the leakage of amniotic fluid. If there is too much discharge, consult your doctor for a special test.

In most cases, the baby’s head drops into the pelvis at 38-39 weeks, this is called cephalic presentation. If the child lies straight with his head down, this is called a longitudinal position, if a little at an angle, then it is oblique. There is also the concept of fetal position: I position means that the back is turned towards the left uterine wall, and II - towards the right. An ultrasound will tell you how the fetus is positioned.

At birth, doctors assess the child’s condition using several parameters: activity, muscle tone, heartbeat, breathing, skin color, reflex reactions. The more points, the healthier your baby was born.

We have now completed our journey through 40 weeks of fetal development during pregnancy. The most important thing is to be attentive to yourself and the words of your doctor, the orders of tests and ultrasounds, pay attention to all the sensations and enjoy pregnancy and future motherhood.