The physiological changes of women during pregnancy

2021-03-21 12:00 AM

Fetal survival with very early active endocrine glands starting at week 11; These glands include the pituitary, thyroid, adrenal, pancreas, and genitals.

During pregnancy, a woman's body makes great changes. The whole body is involved in pregnancy. All of these changes are caused by neurological and hormonal causes.

Also because endocrine functions have played an important and decisive role, we first mention the major hormonal changes made by a woman during pregnancy, and then derive the changes due to Endocrine-yielding.

Endocrinology of pregnancy

General characteristics of hormonal changes during pregnancy

A lot of hormonal changes occur during pregnancy, the most important of which are the placenta that produces human chorionic gonadotropin (hCG), the placenta hormone. (human placental lactogen - hPL), prolactin, progesterone and estrogen. A pregnant woman's hormone levels are different from non-pregnant women and depend on the following factors:

The existence of the placenta, the rich source of steroid hormones and peptide hormones.

Fetal survival with very early active endocrine glands starting at week 11; These glands include the pituitary, thyroid, adrenal, pancreas, and genitals.

Increased levels of estrogen circulating in the blood.

Placenta's ability to regulate the transport of molecules exchanged between mother and baby.

Properties of endocrine changes

There are 5 important properties as follows:

Chemical nature:

Steroid hormones (eg, progesterone and estrogen).

Peptide hormones (eg, hCG and prolactin).


That placenta is an important source of hormones including hCG and hPL.

In the early stages of pregnancy, the source of hormones is mainly derived from the mother, when the pregnancy progresses, after the first three months the fetus produces thyroid hormones, oatotropic hormones, and sex steroids; The placenta by the first trimester produces a large amount of progesterone.

Sometimes a hormone comes from a variety of sources, such as estriol, from the mother, the placenta, or the fetus.

Test methods:

Pure urine test (pregnancy test ..).

24 hour urine test (urine estriol ..).

Maternal blood test (hCG, estriol ...).

Amniotic hormone concentration test: androgen test to determine the sex of the fetus and hypothyroidism.

Dynamic test: As for determining the deficiency of placenta sulfatasa, dehydroepiandrosterone sulfate (DHEASO4) is given to the mother and then her estrogen production is measured.

Normal threshold:

It is important to recognize the normal threshold of hormones during normal pregnancy to distinguish them from an abnormal pregnancy and an abnormal fetus.

Meaning of hormones:

A very high hCG may be suggestive of fibroblasts associated with pregnancy.

Progesterone deficiency in early pregnancy can be thought of with luteum in pregnancy.

Hormone gonotropic placenta (human chorionic gonadotropin - hCG)

Chemical nature:

hCG is a glycoprotein consisting of two subunits alpha and beta. Molecular weight 35,000 dalton.

The alpha subunit of the hCG molecule has the same chemical structure as the alpha subunit of:

Luteinizing hormone (LH).

Follicle-stimulating hormon (FSH).

Thyroid-stimulating hormon (TSH).

The beta subunit has a chemical structure specific to the hCG molecule.


hCG is secreted by osteoblasts of:

Organize the placenta normally very early, about 6 to 8 days after fertilization.

From a lot of vegetable cakes (multiple pregnancy).

Pregnant eggs.

Membrane carcinoma.

Ectopic pregnancy.

Test methods:

Test for the concentration of hCG in the blood or urine by biological methods or immunological methods. Immunoassay methods have greater sensitivity and specificity than biological methods and have become conventional testing methods today.

Biological test:

The rabbit test (Friedman) measures maternal hCG levels based on the potential for oocyte in rabbits 12 hours after hCG injection.

The frog test (Galli-Mainini) measures the amount of sperm released in a male frog's ejaculate tube after injecting hCG into the debris.

Rat test (Aschheim-Zondek): Measures follicles that develop after hCG injection.


Latex agglutination test: Determine hCG in urine; This is a rapid test, a positive hCG test 28 days after fertilization

Immunological test, immunoassay: Beta hCG test in the blood, positive test about 8 days after fertilization.

Normal threshold:

hCG increases rapidly after 8 days of fertilization, every 2 to 3 days hCG levels double and reach a peak around day 80, then decrease and progress to the plateau during the next phase of pregnancy. hCG can be detected during pregnancy.

hCG increases with multiple pregnancies.


Maintains the function of the corpus luteum secreting progesterone.

Stimulates leydig cells of the male fetus to produce testosterone, this effect in coordination with gonadotropin hormones of the fetus. Thus, hCG has an indirect effect on the development of the external genital organs of the male fetus.

HCG is used to detect and track a pregnancy. 

Low levels of hCG in early pregnancy indicate poor pancreatic function, often of miscarriage or ectopic pregnancy.

High levels of hCG often refer to multiple pregnancies or cultured fibroblasts.

The hCG test is used for postpartum follow-up and treatment of cultured fibroblasts.

hCG is used clinically to induce an oocyte in the absence of an oocyte based on its LH-like properties.

hCG has some of the same activities as TSH.

Placenta hormone (HPL)

Chemical nature:

HPL is a peptide hormone that acts like growth hormone (GH) and prolactin. Molecular weight 22,000 dalton.


HPL is produced by the placenta very early, about 3 weeks after fertilization and is detected in the mother's serum about 6 weeks. It goes away quickly after childbirth. The half-life is about 30 minutes.

Test methods:

HPL is tested by radiological immunoassay.

Normal threshold:

HPL was detected in maternal serum from 6 weeks, increased slowly in the first 3 months and 3 months, with very little threshold fluctuations, and disappeared rapidly after delivery.

HPL changes directly depending on the volume of the cake and the number of pregnancies.


HPL has growth hormone properties in the second half of pregnancy:

Causes lipid breakdown and increases the amount of free fatty acids in the blood plasma, providing energy to the mother.

Has the effect of inhibiting the absorption through glucosa and glucosa to mothers.

Effect increases the concentration of insulin in the serum, facilitates protein synthesis, creates a supply of amino acids for the fetus.

HPL test to evaluate the function of the placenta.


Chemical nature:

Prolactin is a peptide hormone with a molecular weight of 22,000 daltons.


There are three main supplies during pregnancy:

Maternal anterior pituitary gland.

The anterior pituitary gland of the fetus.

The uterine lining of the uterus.

Test methods:

Prolactin in serum and in amniotic fluid is tested by radiological immunoassay.

Normal threshold:

Normal prolactin levels in non-pregnant women are between 8 and 25 ng / ml. If the concentration is above this threshold, it can be related to the following factors:

Use of certain drugs that increase prolactin levels (eg, phenothiazines)


Pituitary tumor.

Pathology of the hypothalamus.

During pregnancy, maternal prolactin levels increase to a maximum at full term, with concentrations around 100 ng / ml.

Prolactin levels in amniotic fluid also increased significantly. The origin is from the anterior pituitary gland of the mother as well as that of the fetus, organizing the membranes.


Prolactin prepares the mammary glands for lactation.

Prolactin in amniotic fluid helps to regulate the metabolism of salt and water in the fetus.

Prolactin levels of pregnant women are higher than those of non-pregnant women, because they are physiological, not due to tumors. In cases where pituitary tumors increase prolactin secretion during pregnancy, it is necessary to monitor the visual microscopy to detect tumor growth.


Chemical nature: Progesterone is a D-4,3-ketosteroid hormone containing 21 carbon molecules.


In the absence of pregnancy progesterone is produced by the ovaries, testes, and adrenal cortex.

In pregnancy, progesterone is produced by two main sources: by the gestational corpus luteum up to 7 and 8 weeks, then produced by the placenta until delivery. The gestational luteum begins to transfer to the placenta to produce progesterone from week 6 to week 9, the source of progesterone from the corpus luteum is of negligible significance. The clinical point to emphasize is that the progesterone produced by the corpus luteum is significant to maintain pregnancy up to 8 weeks.

Test methods:

Progesterone is quantified in serum by the radioactive immunoassay method and the enzyme immunoassay method. Day and night rate did not affect the concentration of progesterone in the blood.

Some laboratories prefer the enumeration of pregnanediol, a major metabolite of progesterone, which is quantified in the urine for 24 hours using a chromatographic method.

Normal threshold:

During the period without fertilization of the progesterone produced by the corpus luteum, which is a sign of oocyte release, progesterone production can reach a maximum concentration of 25 mg / day, and measured in peripheral blood a concentration of about 20. 25 mg / ml.

During pregnancy, in the luteal phase, progesterone increases slightly due to the stimulation of hCG.

When the placenta progesterone supply complements the corpus luteum source, the progesterone concentration increases rapidly.

Progesterone levels decrease transiently between 7 and 8 weeks, which is the time of the transfer of the corpus luteum to the placenta in progesterone production. This slight change only happened for about 1 day.

Progesterone levels continue to rise until farrowing, at which point the placenta produces about 250 mg / day.

Progesterone is produced in large amounts in multiple pregnancies.


Progesterone has the following properties:

Prepare the endometrium for the egg to implant.

Maintain the endometrium.

Stretches the muscles of the uterus.

Prevent uterine contractions.

Has a diuretic effect, stimulates increased secretion of aldosterone during pregnancy.

It is considered to be the steroid source for the fetus to make hormones during pregnancy:

Progesterone of the placenta is used by the fetus: in the adrenal cortex to create corticosteroids, the testicles to create testosterone.

The maternal source of progesterone supplements the fetus in the case of relatively lacking of the enzyme 3-b- hydroxysterod dehydrogenasa, the enzyme needed to convert steroids into D-4,3-ketosteroid.


Chemical nature:

Estrogen is a steroid.

There are 3 classic types of estrogens with different amounts of hydroxyl groups:

Estrone is a relatively weak estrogen with a third position of hydroxyl group.

Estradiol is the most powerful estrogen with two hydroxyl groups at the 3rd and 17th position.

Estriol is a very weak estrogen with three hydroxyl groups at positions 3.17 and 16. During pregnancy, estriol is produced in large amounts (1000 times more than in the absence of pregnancy), and is the hormone produced. the most compared to other estrogens.


Production of estriol depends on maternal metabolism, placenta, and fetal metabolism. This complex process has two main biochemical features:

The amount of precursor required is large enough to make the specific steroid.

The organization to convert precursors into specific steroids must have the appropriate enzymes:

The fetus has the following enzymes that are not present in the placenta:

Yeast synthesizes cholesterol.



Placenta has the following enzymes that the fetus does not have:


3-b- hydroxysterod dehydrogenasa.

The placenta is not as capable of producing cholesterone as a mother or fetus does.

The steps in the estriol synthesis are as follows:

Cholesterol is sourced mainly from the mother, and it is converted into pregnenolone and progesteron by the placenta.

The placenta prenenolone enters the fetal circulation, along with prenenolone synthesized by the fetal adrenal glands, partially converted to prenenolone sulfate.

Prenenolone sulfate is converted to DHEASO4 by the fetal adrenal glands. This is the main precursor for the placenta to synthesize estrone and estradiol by hydrolysis of the sulfate group, converting DHA into androstenedione and aromatic multiplication.

DHEASO4 is converted to 16-a-hydroxyl DHEASO4 by fetal liver.

16-a-hydroxyl DHEASO4 is converted into estriol by the placenta in 2 steps:

The action of sulfatasa yeast will remove the sulfate radical.

The action of aromatizing enzymes turns into structures with estrogenic properties.

Estriol accounts for up to 90% of the estrogen component in the mother's circulation.

The formation of estriol is contributed by the mother, the fetus, the placenta.

Test methods:

Estriol is tested in a 24-hour urine and peripheral blood sample.

The test for estriol in the blood by the radioactive immunoassay method gives rapid results, but the estriol concentration is influenced by the day-night rhythm, which peaks usually in the early morning.

A 24-hour urine estriol test by chromatographic method, which is unaffected by day and night rhythms.

Normal threshold:

Estriol is produced in significant quantities at the beginning of the middle 3 months, after which it continues to increase until almost farrowing.

Urinary estriol concentrations reach 25-30 mg / day at near term gestation.

Low or non-estriol estriol levels are often associated with:



Mother used corticosteroids.

Congenital atrophy of the adrenal glands.

Placenta sulfatasa enzyme deficiency.

The estriol concentration decreases or does not increase in the following cases:

Mother has kidney disease.

High blood pressure during pregnancy.


Late pregnancy in uterus.

A large amount of estriol is produced in case of Rh multiple pregnancy and Rh immunomodulation.


Estriol is an indicator of normal activity of the fetus, it depends on the normal functioning of the adrenal cortex and liver of the fetus.

Estriol is an indicator to show the normal activity of the placenta, it is dependent on the production of pregnenolone and the enzyme converting 16-a-hydroxyl DHEASO4 of the fetus to estriol.

When the estriol level falls below normal, or does not increase during pregnancy, other investigative measures such as ultrasound, monitoring, amniocentesis and amniocentesis are needed to assess the condition of the fetus and vegetables.

Physiological changes in female genitals

Changes in the body of the uterus

During pregnancy and childbirth, the body of the uterus is the most changed part of the body. Eggs nest in the uterine lining, where it forms vegetable cakes, vegetable membranes, making the amniotic chamber to accommodate the fetus. During labor, the uterus gradually turns into an out-tube. In response to that requirement, the uterine body changes in size, nature and location.


The uterus during pregnancy weighs 50-60 g. At the end of pregnancy, the uterus weighs almost 1000 g. When not pregnant, uterine depth measures 6-8 cm, but at the end of pregnancy up to 32 cm. The uterine body also develops irregularly. In the first half of pregnancy, uterine organization thrives and weight increases mainly in this period. In mid-gestation, in the 4th - 5th months, the thickest uterine wall, about 2.5 cm, while not pregnant is only 1 cm thick. At the end of pregnancy, the uterine body thickness decreases to 0.5 - 1 cm. This important development of the uterus is due to three factors: the uterine fibers themselves have proliferated, the blood vessels, including the arteries, veins and capillaries all increase and erect. . In the end, as well as the entire body and other genital organs, The uterus retains a lot of water. The enlarged uterine muscle is also due to the formation of new muscle fibers, along with the hypertrophy of muscle fibers. The muscle fibers can grow 3 to 5 times as wide, 10 times as long. During the second half of the exercise period, new muscle fiber creation has been reduced or stopped. During this period, if the uterine muscle is larger than before, it is mainly due to edema and hypertrophy.


In the absence of pregnancy, the uterine muscle density is firm and elastic. But during pregnancy, the cells are congested so much, completely soft, easy to settle down. The cervix may be invisible and the body of the uterus separates from the cervical mass. It is the Hegar sign that is often mentioned when diagnosing pregnancy in the first few months. During pregnancy, the smooth muscles throughout the mother's body decrease in tone, so the uterus also suffers from the same condition and softens.

The ability to shrink and contract:

Has greatly increased. That is the hallmark of pregnancy. Without pregnancy, not much change in a relatively short time. During pregnancy, the volume of the uterus shrinks to 2/3, from being completely soft, can become firm. This shrinkage ability can also be used to diagnose pregnancy. The ability of the uterus to increase contraction is due to two factors: uterine muscle fibers have increased their excitable condition, making it easier to contract, and during pregnancy, muscle fibers are often in a dilated state. Easy and ready to shrink.


During the first 3 months, the uterus is round like a balloon, the anterior and posterior diameters grow faster than the horizontal diameter. The lower part is bulging, can be seen through the same vagina (noble sign). During these months, the shape of the uterus is irregular because the fetus does not occupy the entire uterine chamber, making the uterus asymmetrical. This property can also be used to diagnose pregnancy and is called the Piszkacsek sign. In the middle 3 months, the uterus is ovoid, extremely small below, extremely large above. The bottom of the uterus is enlarged, especially on the back. Later when the fetus has grown, the uterus has a shape of the fetal position inside the uterus: egg-shaped, heart-shaped, raft-shaped, etc.


When not pregnant, the uterus is in the subframe. When pregnant, it grows and moves into the abdomen. Regardless of the first month, the uterus hides behind the pubic joint, from the second month on, on average, the uterus grows 4 cm above the pubic joint every month. Thanks to the essence that develops according to the height of the uterus, one can calculate the gestational age using the formula:

Gestational age (months) = {Height of uterus (cm)} / 4.

Also, during pregnancy, the left angle of the uterus is slightly directed forward, since the abdominal cavity on the right side of the spine is wider, so the right horn of the uterus sinks to that side deeper. The left horn of the uterus protrudes forward.


When not pregnant, the uterus is divided into 3 parts: body, waist and neck. The uterine wall has 3 parts: the peritoneum, the muscle and the mucosa.

Enlarged peritoneum according to uterine muscular layer. In the upper part of the peritoneal uterus attaches to the muscle layer. In the lower part of the uterus, the peritoneum can be easily removed from the muscle layer, because between the glandular and the muscular layer has a rather thick connective organization. That is the boundary to distinguish the segment of the uterus from the lower uterine segment. At this boundary there is a rather large horizontal vein. Taking advantage of the property of separating the peritoneum from the muscular layer below the uterus, a caesarean section is done through the lower segment to be able to cover the peritoneum after recovering the incision edges of the uterine muscle.

The uterine body has 3 muscle layers: the outer muscle layer, the inner muscle layer and the muscular layer in the middle. The knit muscle layer is very important, because there are many blood vessels in the network of this muscle layer. When giving birth, the muscle layer is tightened, tightening the blood vessels, ensuring no bleeding. It is physiological hemostasis.

Change in the waist of the uterus (lower uterine segment)

Before getting pregnant, the uterus waist is just a small ring, only 0.5 - 1 cm in height. During pregnancy, the uterine waist is enlarged, long, and thin, turning into the lower uterine segment. That is due to the gradual fetal birth. Until labor, the lower uterus is about 10 cm long. Thus the lower segment is established gradually throughout pregnancy. But the lower segment is only completely formed during labor, thanks to the contraction of the uterine muscles. For the male, inferior formation occurs from the beginning of the ninth month. In the chicken, the inferior stage is established in the early stages of labor.

The lower uterine segment has an important role in childbirth. Regarding the structure of the lower paragraph there are only two layers. The outer muscle layer and the inner muscle layer, there is no interlocking muscle layer. Therefore, the epithelium formed in the lower segment is not as thick as the body segment. Therefore, the lower uterine segment is the most fragile part of childbirth, the most likely to bleed when there is low adhesion.

Changes in the cervix

The cervix changes less than the body of the uterus. During pregnancy, the cervix softens, softens from the outside to the center. So in pregnancy, in the first few weeks of the cervical examination like a wooden pillar wrapped in velvet. A crow's cervix is ​​softer than a human's. The position and direction of the cervix does not change. But when the lower segment is formed, the cervix usually turns toward the sacrum, as the lower segment develops more on the front than back.

During pregnancy, the epithelium of the cervical canal turns purple because the blood vessels underneath become an erection, which is a sign that Chadwick begins to appear between 6 and 8 weeks of pregnancy. 

The glands in the cervical canal are also not secreted or secreted very little. The thick and opaque cervical mucus forms a plug that seals the cervical opening, protecting against second insemination and from upper genital infections. Only when the labor of the cervix is ​​cleared and opened, the mucus is expelled, folklore is often called "banana resin".

Change in vagina, vulva

During pregnancy, the epithelial layers in the vagina do not develop, not mature to form the surface layers of cells, the nucleus clumped as when not pregnant. Therefore, the vaginal smear will show a very low coagulation index in a pregnant woman. The plaque cells have many spindle cells. Based on vaginal cytology tests can evaluate the hormonal performance of pregnant women from which prognosis in terms of pregnancy. But meanwhile the vagina elongates and relaxes, partly due to the elastic properties of the vaginal wall increasing, partly because cellular factors also increase. Thickened vaginal epithelium, vaginal buds are puffy and sometimes raised, there are many dilated veins below the vaginal epithelium, making the vagina purple in color. The fluid in the vagina has become more acidic, which prevents pathogens from multiplying.

Large lips and small lips have dilated veins that can also be seen with the naked eye. Under the skin there are rich veins that give the clitoris a purple color.

Changes in the ovaries

During the first trimester, the corpus luteum continues to develop, the fetal luteum is larger than the menstrual luteum, the ovarian sac is not ripe, the woman is not menstruating. However, there are cases of menstruation during pregnancy, although it is not normal. The oocyte in this case grows to a certain extent and then atrophy. The ovaries during pregnancy are as congested as other genitalia, and are swollen, enlarged and heavier. Pregnant over 3 months, the corpus luteum gradually regresses.

Change in oviduct

During pregnancy, the oviduct does nothing. However, congestion and soft tissue have also occurred. A few places on the oviduct may also develop oocyte production (which turns into an ovulatory membrane), especially when pregnancy begins. Reproduction can occur in other places, in parts of the abdominal cavity, that is, outside the uterus and fallopian tubes.

Physiological and anatomic changes outside the genitals

Breast changes

The milk glands and ducts develop, causing the breasts to become large and tight. The woman has a feeling of erection. Increased circulation, bulging veins, enlarged nipples, dark areola, prominent Montgomery buds. Milk can be diluted when rectifying, especially in the last months.

Changes in the skeletal system

Especially when the joints are soft and stretched, especially those of the pelvic joints. The pubic, sacral - tail joints have stretched and softened, making the pelvis easier to change and increasing the width to make childbirth easier.

Skin changes

Skin can have dark spots, especially on the face, on the cheeks, giving pregnant women a special look. In addition, the stain can be on the abdominal wall, in the middle white line. The abdominal wall expands suddenly so it splits open. In humans, the cracks are dark blue due to the accumulation of iron pigments. After childbirth, the cracks do not disappear but gradually fade, leaving a mother-of-pearl white.

Changes in the circulatory system

Blood volume:

During pregnancy, blood volume increases to about 1500 ml, sometimes up to a half times normal. That means when the body normally has 4 liters, it can increase to 6 liters during pregnancy. But the increase is much more in terms of plasma than blood cells. As a result, the number of red blood cells in the blood is slightly reduced, the rate of hemoglobin decreases, the rate of blood depression decreases. This increase partly meets the requirements of increased blood flow, making blood flow in the uterus - vegetable circulation improved.

This increase also explains blood thinning tends to cause hypochromia, and decreased osmotic pressure.


The diaphragm is pushed up, the posture of the heart has also changed. The heart is horizontal, the height decreases, but the heart area does not change. Cardiac output also increased by 50%, highest in 7 months, then decreased gradually until delivery. Heart rate increased. The audible systolic murmur, the mechanical blow in the final months, may be due to the major drop in blood viscosity.

Blood vessel:

During several months of pregnancy, the enlarged uterus presses on the lower aorta and the sub-vena cava veins congestion of the lower extremities, obstructing the circulation of the circulation, so venous blood pressure increases. Arterial blood pressure does not change despite the increase in cardiac output, as the blood vessels are elongated and enlarged. The most bulging veins are those in the lower extremities and vulva. In the rectum, because of the swelling of the veins and constipation, pregnant women often have hemorrhoids.

Respiratory changes

In the final months, the uterus enlarges, pushes the diaphragm upwards, the woman breathes shallow and fast. In people whose uterus is too large such as in the case of an enlarged pregnancy, twins, multiple amniotic fluid, often have difficulty breathing, rapid breathing.

Changes in digestion

During the first trimester, pregnant women often experience vomiting, nausea, and love to eat strange foods, often called bad food, or sour food, which are often referred to as morning sickness symptoms. Probably caused by endocrine disorders. From the 4th month onwards, the symptoms above go away, the pregnant woman has returned to normal eating and drinking, and her appetite increases compared to before pregnancy. The bowels are often constipated due to reduced bowel movements and compression of the colon.

Changes in urology

The ureter has decreased muscle tone, often decreased peristalsis, is long and curled, and thus has poor urine drainage. Especially while the uterus grows and compresses the ureter, pyelonephritis is more likely to occur, pyelonephritis and pyelonephritis due to stasis and reverse infection are not uncommon.

Nerve changes

During pregnancy, it is easy to have changes in psychology, emotions. The woman is often irritable, her memory is impaired. There are also sympathetic and parasympathetic changes. Poor appetite, insomnia, and nausea in the first few months can be partly caused by neurological changes. Neurological changes are closely related to endocrine changes.

Body changes

From a physiological standpoint, the systemic changes are derived from the proliferation of the extracellular and plasma areas.

Mechanism of water retention

Water retention is caused by two main reasons:

Increases water and salt return of the renal tubules.

Increased secretion of aldosterone.

Alter the posterior pituitary test of urinary secretion. There appears to be no increase in antidiuretic hormone secretion in pregnant women, but there is a particular increase in sensitivity to this hormone.

Consequences of water retention

Increased blood volume dilutes the blood.

Increase cell foreign retention:

This phenomenon occurs in all organizations and agencies. The common increase in cytostatic fluid retention leads to a common physiological phenomenon, edema, although edema is always a concern in pregnant women. In addition, the water permeability during pregnancy has reduced the tonicity and tenderness of the organs in a special way such as:

Gastrointestinal tract (bloating and constipation).

Urinary tract (dilated ureter and stasis)

In particular, the different changes in the fibers of the sac, and the ligaments of the joints, makes the joint dilation increase, especially the pubic joint.

Increases metabolism and changes in some physiological constants

The synthetic metabolic process dominates over the degenerative metabolic process, with a strong positive nitrogen balance. Through these changes, some biological constants differ between those who are pregnant and those who are not. Here is a summary of some of the key changes:


Temperatures are above 37 degrees C during the first 3 months, meaning that the plateau temperature continues during the second period of the cycle. Then the temperature dropped below 37 degrees Celsius.


Slightly increased.

Blood pressure:

Arterial blood pressure is slightly lower, below values ​​seen outside of pregnancy. Blood pressure is slightly low during early pregnancy, and then gradually increases, but remains within the normal range. If the blood pressure is above 140/90 mmHg, it is pathological.


Hematocrtit slightly decreased, between 30 and 40%.

Red blood cells are typically less than 4,000,000 in 1 mm3.

WBCs range from 8,000 to 16,000. Normal formula.

Platelets increased from 300,000 to 400,000.

Protit from 60 to 70 g / liter, serine / globulin ratio decreased.

Serum calcium and iron slightly decreased.

Reduced alkali reserves.

Slightly high blood pH = 7.6.

In addition, serum urea, iodine and serum glucose are unchanged.

Body weight:

In the first 3 months, the increase must not exceed 1.5 kg. In the middle 3 months an average increase of 0.5 kg per week, a total of about 6 kg. In the last 3 months, increase 4-5 kg.

Especially have to monitor the weight in the middle 3 months. If there is a sudden increase in this period, a fetal toxicity must be suspected. In the last 3 months, there was an uneven increase. Usually 1 - 1.5 kg increase suddenly in the last weeks.


The amount of urine excreted increases depending on the person. Low urine density. Urine urea and iodine did not change.

Other tests:

The rate of blood depression slightly increased, from 10 to 30 mm in the first hours.

The filtration rate of urea, PSP is normal.

Red blood cell and white blood cell count in a normal minute. At the same time, tests cause hyperglycemia, bleeding time, blood clotting, and normal prothrombin ratio.