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What happens in the body of a woman during pregnancy?
Last reviewed: 19.10.2021
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First, during pregnancy there is a change in the quantity and quality of hormones. And you already know about one of them. This is a chorionic gonadotropin. It is produced by one of the membranes of the fetal egg after implantation (fixation) of it in the uterus. It stimulates the yellow body to continue the secretion of progesterone - a hormone that ensures the preservation of pregnancy. First, progesterone is produced by the yellow body, and then by the placenta.
Estrogens at the beginning of pregnancy are also produced by the yellow body, and then six to seven weeks later by the placenta. Their main role is to ensure the growth of the uterus, mammary glands and fetus. The number of estrogens is the criterion for assessing the function of the placenta and the development of the fetus. A sudden decrease in their number serves as an indicator of the violation of this unity.
Placental lactogenic hormone affects fetal growth. Appears in the blood of a pregnant woman five weeks after the last menstruation. If its number is below the norm, this is a risk for the developing child.
Oxytocin is produced by the pituitary gland and stimulates uterine contraction during pregnancy and childbirth. Early and increased secretion of it can cause premature birth.
In addition to the hormonal composition, changes affect other organs and systems.
The weight of the uterus increases from 50 g in the non-pregnant state to 1 kg by the end of pregnancy. In addition to the shelter for the embryo, the uterus has another role - to expel the fetus. For this, her muscle mass grows. Enlargement of the uterus can lead to compression of the veins in the abdominal cavity, which worsens the venous outflow from the lower extremities. This can cause varicose veins on the legs.
The respiratory system is also somewhat activated. First, the developing fetus in the process of its life releases carbon dioxide (CO2), which, getting into the blood of the mother, increases the overall level of CO2 in her blood. Because of this, the woman's breathing becomes deeper and more frequent. Secondly, an increase in the volume of circulating blood and an increase in the work of the heart entail an increase and deepening of the breathing due to the constant relationship between the amount of blood flowing through the lungs and the volume of inhaled air. In addition, the increased rate of breathing occurs due to the increase in the size of the uterus, which presses on the lungs, reducing their volume.
The weight of a woman is increased by 10-12 kg. To a greater extent this is due to the increase in liquid (up to 7 liters). If the mass is growing too fast and too much, edema appears. This is an excuse to sound the alarm and go to the gynecologist, as these are signs of a toxicosis of pregnant women.
The cardiovascular system, or the circulatory system, also undergoes changes: the volume of circulating blood increases, and the volume of plasma increases to a greater extent than the number of erythrocytes. This is necessary for more dilution of blood (so that it flows better through the vessels). In this regard, in pregnant women the hemoglobin is somewhat decreased (about 130 g / l, and in pregnant women - 105-110 g / l). At the same time, some gynecologists immediately diagnose: anemia of pregnant women. (And it would be fine to just make a diagnosis, and then even start to treat, and put in the department of pathology of pregnant women.)
An increase in the volume of circulating blood leads to more than usual cardiac tension - there is a tachycardia (rapid heart beat).
Blood pressure should remain the same throughout the pregnancy. Therefore, if by the end of pregnancy it rises, it is an occasion to consult a doctor. Elevated blood pressure along with edema and the appearance of protein in the urine - a sign of toxicosis of the second half of pregnancy - pre-eclampsia.
Urination becomes more frequent due to the increased uterus, which starts to squeeze the bladder.
Memory begins to suffer - along with a general increase in the body's fluid, in the brain its amount decreases. This is caused by a deterioration in memory, a decrease in some intellectual skills (it is more difficult to solve crossword puzzles) and changes in the emotional sphere. In this very often, women want to get some sleep. (And do not deny yourself this.) And some people want to cry all the time, it becomes a pity for themselves - such a "miserable" and "abandoned" by all.