Size of the abdomen during pregnancy: abdominal circumference by week, fetal development, photo

2024 Author: Priscilla Miln | [email protected]. Last modified: 2023-12-16 00:21

The size of the belly during pregnancy greatly depends on the personal characteristics of the girl's body structure. In some expectant mothers, the belly appears very late, while others observe the appearance of rounded shapes in the initial stages.

The size of the abdomen increases during pregnancy, subject to a systematic increase in the fetus in the womb and the amount of amniotic fluid. Small changes in the volume of the abdomen can be noticeable to the mother herself from the third month, while others will be able to assume the position only from the 20th week. During this period, the belly becomes quite noticeable, but many girls with curvy figures will be able to hide it for much longer.

What determines the size of the abdomen during pregnancy by week

The photo below clearly shows the change in belly size from week to week. Specialists in the process of performing measurements adhere to generally accepted standards, however, they take into account the fact that they can vary significantly inon a case-by-case basis.

Among the list of conditions that affect the change in the circumference of the abdomen, focus on the following:

• physique of the expectant mother;
• intensity of weight gain - many pregnant women have a high appetite;
• parameters of the unborn child;
• baby position;
• Amount of amniotic fluid.

For expectant mothers predisposed to fullness, roundness can be inconspicuous until the very stage of childbirth, while women with a narrow pelvis and a fragile physique meet with a change in the size of the abdomen at the very beginning of the second trimester. The size of the abdomen during multiple pregnancy increases instantly, as a result of which an interesting position can be noticeable to people around much earlier.

The belly may not grow systematically, but in jerks. Obstetrician-gynecologists do not begin to trace the dynamics of adding centimeters in the circumference of the abdomen not immediately, but, as a rule, from the fifth month.

The largest belly size by week of pregnancy, the photo of which is attached, is at 38 weeks. By this time, all the main stages of fetal development are over, and the bottom of the uterus reaches the limit. There is no need to panic if the stomach becomes smaller at 38 weeks, most likely the child has taken a different position, because he is preparing for an early meeting with his mother. Just before the date of the appearance of the baby, the height of the fundus of the uterus decreases, the "lowering of the tummy" occurs. Let's try to figure out what determines the size of the abdomen during pregnancy (photo shownbelow).

How to accurately measure the belly?

It is important to measure the stomach correctly, as the inaccuracy shown can be a significant cause for panic.

Women are especially sensitive during pregnancy. An excuse for their concern may be a discrepancy of two centimeters. Undoubtedly, in this case, you need to pull yourself together. This is because all indicators are individual.

Measurements are made with a centimeter tape in this way:

• The mother-to-be needs to stand up straight.
• Place the measuring tape at the level of the navel.
• Better to measure at the same time.
• You can not determine the circle of the abdomen in more protruding places - this is wrong.

If the obtained values are slightly different from the generally accepted standards, there is no reason to panic at all. This is due to the fact that the change in coolant is greatly influenced by numerous conditions, for example, the amount of amniotic fluid. This size can change significantly during the entire period of gestation.

A significant change in indicators before the very birth can be a cause for concern. Such differences may indicate that diligence has changed, and problems may arise during childbirth. Doctors in this case assess the condition of the child and decide on the option of delivery (independent or by caesarean section).

In each case, significant differences in the characteristics of the girth of the abdomen from generally accepted measurements are a reason to visitgynecologist. Only after a medical examination can it be established whether this is the norm or a cause for concern.

Abdominal circumference

The circumference of the abdomen during pregnancy by week is a significant and trackable characteristic. It is measured in accordance with the gestational age and compared with tabular indicators. Determination of the circumference of the abdomen is performed from the 20th week.

The values make it possible to assess the rate of intrauterine development of the child.

During any routine examination, the doctor establishes the systematic development of the fetus in the uterus. The girl for this is obliged to lie down on the couch. The doctor, using a centimeter tape, sets the length from the side of the pubic joint to the prominent place of the lower uterus. In a similar way, the level of the uterine fundus is measured.

Such actions make it possible to control the increase in size in the abdomen. Usually, starting from the fifth month, the pregnant tummy grows by 1 cm per week. The circumference of the abdomen by weeks of pregnancy is certainly compared with the height of the fundus of the uterus. Normally, these characteristics must meet a certain deadline.

Uterus size during pregnancy

The increase in the volume of the uterus occurs throughout the entire pregnancy. In the first few weeks, the uterus is pear-shaped. By the end of the 8th week of pregnancy, its size increases by about 3 times, the uterus takes on a rounded shape. Throughout the second halfpregnancy, it retains its own rounded shape, and at the beginning of the 3rd trimester it acquires an oval shape. Before pregnancy, the weight of the uterus is up to 100 g, and at the end of pregnancy - 1000 g (the uterus increases more than 500 times). Over the entire period of gestation, each muscle fiber becomes 10 times larger and about 5 times denser. The vascular network of the uterus increases significantly, according to its own oxygen regime during pregnancy, it approaches similar vital organs (such as the heart, liver and brain).

The photo below shows how the height of the uterus changes by week, which are indicated by numbers in the picture.

At 4 weeks of pregnancy, the size of the uterus reaches approximately the size of a chicken testicle.

At 8 weeks, the uterus is already the size of a goose egg.

At 12 weeks, its volume reaches the size of the head of a newborn, the bottom reaches the upper edge of the pubic joint.

After the 13th week of pregnancy, the size of the abdomen increases even more, and the bottom of the uterus is palpable through the anterior abdominal wall.

At sixteen weeks it is halfway between the pubis and the navel. The same will happen at the 17th week of pregnancy. The belly size will not vary much.

At twenty weeks, the bottom of the uterus is 2 transverse fingers above the navel. During this period, the abdomen is already significantly enlarged. This is noticeable even if the expectant mother is wearing clothes.

At 24 weeks, the fundus of the uterus is at the level of the navel.

At 28 weeks it is 3 fingers above the navel.

The size of the abdomen at the 30th week of pregnancy is different for each woman in labor. But the bottom of the uterus should be in the middle between the navel and the xiphoid process of the sternum, the navel begins to soften.

At 38 weeks, the fundus of the uterus rises up to the xiphoid process and costal arches - this is the maximum level of the height of the fundus of the uterus.

At 40 weeks, it drops to half the distance between the navel and the xiphoid process.

Reducing the height of the fundus of the uterus is permissible in the transverse position of the fetus, if the baby is in the womb in such a way that the head and legs are located on the sides. With the transverse position of the fetus, natural delivery is not feasible.

The size of the uterus more than the established gestational age are also with multiple pregnancies. It has been established that multiple pregnancy is a significant risk pregnancy - it increases the possibility of various complications.

The uterus is able to grow intensively with significant polyhydramnios - a condition when the number of amniotic fluid exceeds the norm, reaching up to 2-5 liters, and in some cases - 10-12. This anomaly occurs in diabetes mellitus, Rh conflict during pregnancy, acute and chronic infections, pathologies of fetal formation. Of course, all these conditions require close monitoring by medical professionals.

The uterus may grow faster than usual with large fetuses. Large size may be genetically determined. In other cases, an abnormally large fetus is observed as a result of diabetes in the expectant mother during this pregnancy.

The size of amniotic fluid during pregnancy

Another reason why belly sizes differ at different stages of pregnancy is water. The increase in the volume of amniotic fluid (amniotic fluid) occurs unevenly. Thus, at 10 weeks of pregnancy, their amount is usually 30 milliliters, in the fourth month - 100 milliliters. At 19 weeks of pregnancy, the size of the abdomen increases further, and the amount of amniotic fluid is 400 milliliters, etc. The largest volume is noticed by 37-38 weeks (1000-1500 milliliters). By the end of pregnancy, the amount of water can drop to 800 milliliters. When the baby is post-term, there is a decrease in the amount of amniotic fluid (less than 800 milliliters).

Separately, it is worth considering the condition of the fetus and the size of the abdomen by months of pregnancy.

First month

The union of male and female sex cells leads to the formation of a new one, which is called a zygote.

The cell moves deep into the uterus through the fallopian tube (this period lasts 7-8 days). If the cell reaches the uterus, implantation occurs - the introduction of the zygote into its wall. The implant procedure takes three days. At the prefetal stage, active physical development of the rudiments of organs that appeared during the formation of the embryo takes place, new bookmarks are formed: the stomach and other sections of the digestive tract are released, the intestines are laid, it is divided into sections, the muscles are divided, the skeleton is created.

Woin the second half of the prefetal stage, the facial parts, the neck are formed, the circulatory system and sensory organs are formed, the structure of the brain is differentiated, and large digestive glands - the liver and pancreas - are released. By the end of the second month, the rudiments of all organs are formed and occupy their own permanent position. During the fetal period, there is an increase and multifunctional formation of the organs and tissues of the embryo. In other words, starting from this stage, the organs of the fetus acquire the ability to function.

Second month

In the future baby (its length is already 4-5 millimeters), the bookmarks of the limbs become visible. By the end of the period, the length of the embryo increases (from 5 millimeters to 25-30 millimeters). On the arms and legs there are fingers that are already ready to move; however, these movements are not yet felt by the mother. A rather elongated tail eventually transforms into a slight tubercle. The neck appears. It is worth noting that the brain ceases to be visible through the skin. The rudiments of the sense organs arise from the protrusions and depressions of the brain, while the eyes are almost completely formed. The volume of the head is huge (it is approximately fifty percent of the length of the entire embryo). There is a further formation of the main structures of the face (except for the auricles - they are still very low).

The fetal body begins to function: the brain sends impulses that coordinate the functions of other organs. The rapid growth of the intestinal tract that occurred in the sixth or seventh week leads to the fact that somethe number of intestinal loops ceases to fit in the small abdominal cavity of the embryo and crawls out of its borders - the so-called physical umbilical hernia appears. By the end of the second month, it gets absolute development, and by the tenth week it completely disappears. At the end of the second month, the body is formed, there are rudiments of limbs, still imperfect eyes, nose, mouth are visible in the head, the genital organs of the unborn child are developing.

Third month

Total length - 7 cm, weight - 20 g. During the third month, the child grows very quickly and almost doubles its own length. The head still remains relatively huge and by the end of the month it is approximately one third of the parietal-coccygeal length. The anterior lobe is very small compared to the brain part of the skull. A very rapid growth of the eyelids is noticed, the edges of which grow together at this time (the eyes open only at the seventh month of pregnancy). The initial rudiments of hair appear. Hands and feet produce movements, fingers and toes are clearly visible, initial ossification points appear in the cartilaginous rudiment of the skeleton. During this period, the beginnings of nails appear on the fingers and toes.

Fourth month

The head begins to lag a little in growth, the proportions of the fetus are gradually becoming familiar. Fluffy hair appears on the body. The arms and legs are about the same length. The face begins to take shape, the ossification of the skull occurs, the development of the muscular system is basically completed, the movements of the limbs become more active, however, the motheruntil they are felt, the sex of the baby differs clearly. The child moves a lot, is able to suck his own fingers. The skin has two layers.

The functions of different body systems are improved. When using electron microscopy, it was determined that the structure of the cells in the brain is almost the same as in newly born babies. With the help of a special tube, the heartbeat is heard, the frequency of which reaches one hundred and fifty beats per minute. By the end of the 15th week of pregnancy, the size of the abdomen increases, and it already becomes noticeable to others.

Fifth month

The most rapid body growth occurs, by the end of the fifth month of intrauterine formation, the head is no more than a third of the entire body length. The skin is dark red in color. A hidden fat layer is formed. The skin is intensively overgrown with fluffy hair. At the 18th week of pregnancy, the size of the abdomen increases dramatically, due to the intensive growth of the baby.

The sebaceous glands of the fetus begin to secrete a fatty substance. This lubricant protects the unborn baby from the continuous influence of amniotic fluid, and then simplifies its passage through the birth canal. Meconium is formed in the intestinal tract. Significantly elongated lower limbs. The baby can be born alive, breathes, but is usually not viable at this stage of pregnancy.

Sixth month

The skin becomes very wrinkled. This is due to the discrepancy between the growth rate of the baby and his skincover. Eyebrows and eyelashes become visible. Skin patterns appear on the fingertips. Their pattern is different for everyone - inimitable and unique.

In this period, the formation of cells of the cerebral cortex is basically completed. Their loss under the influence of any damaging conditions is not replenished. A person lives further life with the number of cells that has formed in the cerebral cortex at the moment. Movements of the fetus in the amniotic fluid become more differentiated.

Seventh month

The length of the unborn baby is about 40 cm, weight - 1200-1700 g. The subcutaneous fat layer grows, as a result of which the skin becomes denser and smoother. In the seventh month, the eyelids open. The baby can open and close his eyes. By this period, his entire body is covered with soft fluffy hairs.

All major body systems are sufficiently formed. It is possible, although with great difficulty, with special care in a specialized center for premature babies, to save the life of a child outside the mother's body.

Eighth month

At about seven and a half months, a baby is able to be born and survive. Babies born during the third trimester are usually fully mature. As you approach full-term pregnancy, the chances of having a full-fledged and fully viable, he althy baby increase significantly.

By the end of pregnancy, antibodies from the mother pass through the placenta to the fetus, forming a temporary resistance to diseases that the child has from birththere is immunity. Premature babies receive less of this protection than full-term babies, so the former are the most susceptible to infections.

Ninth month

Approximate growth of an embryo is 45-50 cm. Due to the intensive formation of adipose tissue in the subcutaneous layer, the shape of its torso becomes rounder. The nails on the hands reach to the tips of the fingers. The hair on the head becomes thicker and longer. The child that appeared during this period is viable, cries loudly, opens its eyes, and the congenital sucking reflex immediately appears.

Tenth month

The height of the embryo is approximately 50-55 cm, and the weight is 3-5 kg. By the end of pregnancy, the signs of prematurity disappear, the child appears mature. Relatively rarely, there is a discrepancy between full-term and maturity of the child.

Under negative developmental circumstances (mother's illness, insufficient or malnutrition, etc.), a full-term baby may be immature, which is manifested by insufficiently perfect development of systems or organs. In some cases, the reverse manifestation is also traced: the baby appears a little ahead of time, but mature.