What happens in the 12th week of pregnancy. 12 weeks pregnant: fetal size, baby gender, ultrasound picture

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

12 weeks pregnant is the final stage of the first trimester. During this time, a little man has already developed from a cell that is visible under a microscope, capable of making some movements.

From this period, the second trimester of pregnancy begins, during which a woman can take a break from the unpleasant symptoms of the first weeks and prepare for the responsible third trimester. From 12 weeks of pregnancy, the size of the fetus, the sex of the baby can already be seen on ultrasound.

First trimester

Many expectant mothers ask: "The doctor gave me 12 weeks of pregnancy. How many months is that?". Pregnancy lasts 40 weeks - these are 9 ordinary months or 10 lunar (obstetric) months. In a normal month there are 30-31 days, and in a lunar month there are clearly 4 weeks - 28 days. This is to facilitate monitoring of the development of the fetus: each week is characterized by certain parameters, which makes it possible to suspect the slightest violations during the intrauterine development of the child.

If you are 12 weeks pregnant, how many months is thatthis table will tell you.

If you look at the ratio, then 12 weeks of pregnancy is 84 days. Divided by a calendar month (31 days), it is 2 months and 22 days.

Changes in mom's body

At 12 weeks of pregnancy, what happens in the body of the mother and fetus? What new sensations can a woman have? If the first weeks are dangerous for premature termination of pregnancy, then at this time the probability of self-abortion is minimal. The placenta is already formed, it begins to fulfill its function of nourishing the child, removing metabolic products and synthesizing pregnancy proteins. The speed of blood flow in it increases to 600 ml per minute.

Progesterone - the main hormone of pregnancy - begins to be produced not by the corpus luteum, but by the placenta. It regulates the contractility of the smooth muscles of the uterus, intestines, bladder and ureters. Therefore, frequent trips to the toilet stop, but constipation appears. Heartburn is a symptom that women begin to complain about from 12 weeks of pregnancy. The size of the fetus, the sex of the child, as our grandmothers believed, does not affect the origin of this unpleasant condition. Everything is explained by the relaxing effect of progesterone on the sphincter between the esophagus and the stomach.

Estrogen hormones do not stop being produced: they also play an important role in the development of pregnancy. At week 12, estriol contributes to an increase in the mammary glands, nipples, fluid retention and an increase in the amount of protein in the female body.

The muscle fibers of the uterus continue to grow and grow, and in the period from 12 weeks to 20 - especially intensively. The size of the uterus becomes like the head of a newborn baby, the bottom reaches the womb. The speed of blood flow and the volume of circulating blood in the body due to new changes begin to increase.

The emotional background of the future mother is changing: fatigue, capriciousness, constant depression and dissatisfaction with everything disappear. From the 12th week, a woman seems to be born again, her well-being improves and her working capacity increases. At the same time, the expectant mother begins to have vivid and sometimes amazing dreams. This is due to the fact that fetal hormones act on the subcortex, which begin to circulate intensively, in addition, the size of the fetus increases significantly from 12 weeks of pregnancy. The sex of the baby does not affect which hormones are produced by the placenta.

Hormones at this time

Impulses from the brain stimulate the production of growth hormone, which from the 12th week begins to prepare the mother's genitals for childbirth.

Prolactin begins to be produced from the 12th week of pregnancy. The size of the fetus also enhances its production: the larger the baby, the greater the amount of this hormone in the blood. Under the influence of prolactin, the mammary glands grow and prepare for their main function: the production of colostrum and milk.

From the 12th week, cortisol, a hormone of the adrenal glands, is intensively produced. This substance reduces the susceptibility of the future mother's body to stress and adverse effects.external environment, making it possible to safely carry a pregnancy.

How to behave

The rules of conduct at this time are the same as during the entire pregnancy. Everything should be set up for the normal course of the gestation process. At 12 weeks of pregnancy, the size of the abdomen is not particularly enlarged, and you can engage in mental and physical labor, but without overload and overwork, which contributes to the proper functioning of all systems and organs. You should avoid cycling, sports that are accompanied by body shaking - jumping and sudden movements. Since you can already tell your family and superiors about your pregnancy, it is necessary that you be protected from night shifts, heavy physical labor with heavy lifting and prolonged sitting at the computer, working at height.

Physical exercise: pros and cons

Classes should be started only after consulting with your doctor. You can do yoga, physical education and non-fatiguing sports. High-quality nutrition, work and rest regimen, fresh air and walks before going to bed contribute to a good mood, the physiological course of all processes, and your baby already feels it.

New sensations at this time

The main unpleasant symptoms begin to disappear: weakness, malaise, drowsiness disappear, frequent urination is less of a concern. However, the mood does not improve, and there may be unreasonable aggression. Food addictions gradually cease, and the desire for something unusual to eat disappears. But do not overeat for the joys that morning sickness andvomiting disappeared, because the load on the excretory and digestive organs increases. Under the influence of internal progesterone, the main action of which is to maintain pregnancy, constipation appears.

At 12 weeks of pregnancy, the size of the abdomen does not increase much, especially in primiparas and in women with a body weight exceeding normal. In multiparous women, due to the less elasticity of muscles and skin, the abdomen becomes more noticeable. With multiple pregnancies, the size of the abdomen and uterus does not correspond to the term: they significantly exceed the weeks that are supposedly set by the monthly ones. Measurement of the circumference of the abdomen and the height of standing above the womb of the fundus of the uterus is already possible when visiting the antenatal clinic. Increased pigmentation of the navel and the line connecting the womb with the umbilical ring begins to appear.

From this period, changes occur on the skin: there may be rashes, acne, peeling. But these are isolated cases. Most often, increased blood circulation and estrogen hormones in the mother's body leads to the fact that the appearance of the skin improves, it becomes younger, there is a sparkle in the eyes and a blush on the face. The woman looks better than ever. The so-called inner glow appears - a sign by which they know about your pregnancy.

Mom's body weight becomes 1-2 kg more - this is a normal increase. From this period, the pregnant woman is weighed at each appearance to control weight and for the early diagnosis of latent edema.

Expectant mother begins to feel the pulsation of the aorta, which is mistaken for the movement of the fetus. From week 12, the increase beginsmammary glands, areola and nipples darken, the woman feels light tingling and at the same time the tenderness and importance of her condition.

Baby development

During this period, all the internal organs of the child were formed. At 12 weeks of pregnancy, the size of the fetus and its weight increased by almost 2 times. He already weighs 14-15 g, his height is almost 10 cm.

The little man has arms, legs. The baby's face has eyes with eyelids, a mouth, a nose, nails formed on the fingers, the first rudiments of muscles appeared. The baby's ears are already in place. The child can clench and unclench his fists, move his toes, wince, yawn, open and close his eyes, make swallowing movements. The brain begins to divide into two hemispheres, all its structures are formed, reflexes appear. The heart begins to beat at a speed of 160-165 beats per minute. The intestines have taken their normal position in the abdominal cavity, the liver is already producing bile. Blood cells are represented by erythrocytes and leukocytes. Bone maturation and muscle strengthening occur. In boys, testosterone begins to be produced, and the thyroid gland produces hormones. The immune system begins to function.

At 12 weeks pregnant, a photo of the fetus will show you how your baby has grown. This will be the first picture of the baby.

It is from this period that the most interesting and amazing changes begin: the baby is growing rapidly, the functions of all its organs are improving in order to quickly acclimatize tonew living conditions outside the abdomen. At 12 weeks pregnant, a photo of a fetus on an ultrasound will show you a baby that has grown significantly since conception.

What ultrasound shows

Required studies at 12 weeks of pregnancy - fetal ultrasound and determination of serum markers.

An ultrasound is done to see:

• fetal development according to timing;

• the work of the heart, the rhythm with counting the number of heartbeats;

• placenta status;

• the presence of a second fetus in the case of twins;

• signs of chromosomal abnormalities or malformations;

• state of myometrium: the presence of nodes or hypertonicity with the threat of interruption;

• other pelvic organs in order to identify pathological processes.

Ultrasound at this time can be carried out with a conventional and vaginal sensor and helps to determine the size of the fetus, the sex of the child at 12 weeks of pregnancy, and measure all the main indicators. An important point: determining the exact date of birth. At 12 weeks of pregnancy, an ultrasound photo will show you not a fetus, but already a little man.

The coccygeal-parietal size of the fetus must be measured - the distance from the coccyx to the crown at the moment of maximum extension of the baby. This measurement is taken in the sagittal plane, which divides the body into two equal halves.

Ultrasound is not only necessary to determine the sex of the baby. Although at this time, with the availability of modern equipment, this is also possible. The boy's penis looks likearrowhead, the girl's genitals - in the form of two strips.

Many want to find out the sex of the baby at 12 weeks of pregnancy in order to prepare for the birth: buy the necessary clothes of the appropriate color, prepare the eldest son or daughter for the birth of a younger brother or sister.

For doctors, ultrasound is necessary to detect fetal malformations or chromosomal abnormalities. To do this, measure the collar space. Normally, this indicator is no more than 2.5 mm. If the thickness is 3 mm or more, then this indicates Down syndrome, Edwards, Turner, Patau and other chromosomal abnormalities.

A good marker is to determine the length of the bones of the nose of the fetus. This indicator, if it is 2 mm or more, in 50-80% of cases indicates Down's disease.

At 12 weeks of pregnancy, ultrasound can also show such malformations: anencephaly - the absence of cerebral hemispheres, acrania - the absence of skull bones, ectopia of the heart - its incorrect position, umbilical hernia, defect of the anterior abdominal wall, fused twins, complete atrium - ventricular blockade, in which life is impossible, cystic lymphaginoma of the neck, defect of the anterior abdominal wall, etc.

About the defects, parents must be informed in order to make a choice in favor of further prolongation of pregnancy or its termination. During this period, an abortion can still be performed without serious complications for the woman.

Required and optional studies

To determine the defects of all pregnant women,a blood test for the quantitative composition of serum markers of maternal blood: free subunit β - hCG and placental pregnancy-associated protein (PAPP-A). An ultrasound together with this study is called a screening test, which is not a final diagnosis, but only suggests the development of a child with chromosomal abnormalities.

Accurate diagnosis can be made after invasive methods of prenatal diagnosis. At this time, it is possible to conduct a biopsy of the chorion. Do not be afraid of this procedure. Currently, it is performed under ultrasound guidance, and the risk of complications is minimized.

Some clinics perform other sonographic examinations in addition to ultrasound. At your request, you can take a 3D photo and ultrasound at 12 weeks of pregnancy. For a boy or a girl, however, this study may show an unreliable result. You can double-check and find out exactly the sex of the child at 18-20 weeks with a second screening ultrasound.

Besides urine and blood tests, screening for syphilis, HIV, hepatitis, viral and bacterial infections is mandatory.

Symptoms to watch out for

You need to know the dangerous symptoms that can appear at 12 weeks of pregnancy. What happens to a child if the stomach suddenly starts to hurt or spotting appears?

For pain in the lower abdomen of a different nature, you must immediately call an ambulance or contact your gynecologist. The most common cause of this pain isthreatened miscarriage at 12 weeks of gestation. An ultrasound photo will show the tone of the uterus, sometimes deformation and even placental abruption. But sometimes there are pains that are not related to pregnancy. These are appendicitis, lumbago, flatulence, food infection, renal colic, tension of the ligamentous apparatus of the uterus and others.

Discharge from the genital tract of various colors and volumes is a symptom that requires immediate hospitalization in the gynecological department. This may signal placental abruption and termination of pregnancy. At 12 weeks pregnant, an ultrasound photo will show the exact location and size of the detachment. Intensive maintenance therapy is needed to treat such a symptom at the indicated time.