By the end of the first trimester: height - 6-8 cm, weight - 14-19 grams.
The first trimester is the most decisive in the entire pregnancy, because it is during these 12 weeks that all the organs of the unborn baby are laid.
The vast majority of miscarriages also occur in the first trimester of pregnancy, so it is very important for a woman to follow doctor's prescriptions, take vitamins and lead a healthy lifestyle.
Changes in baby's development occur almost daily. By the end of the third week of pregnancy, the egg is implanted into the wall of the uterus and turns into a fertilized egg. Around it, the placenta, fetal sac and amniotic fluid are formed.
Even at the very initial stage of development in an embryo, it is already possible to distinguish prototypes of brain cells, future blood, skeleton, muscles, genitourinary system, gastrointestinal tract and glands.
By the end of the third month, the rudiments of all organs are forming in the baby, and the formation of the circulatory system is almost complete. Until 20 weeks, the main organ producing blood will be the liver, then it will be replaced by the bone marrow.
By the end of the trimester, the child can listen to the heartbeat with a stethoscope, and on especially accurate devices, you can observe the heartbeat from 21 days after conception!
The child forms a head, on which ears, mouth, eyes are visible (by the end of the trimester, the eyelids are also formed). The arms and legs are separated from the body, and palms, feet and fingers become visible on them, and tiny marigolds are noticeable on the fingers.
The basis of the nervous system is formed: the brain and spine are formed. The brain grows rapidly, so the size of the head is so far superior to all other parts of the body. But by the end of pregnancy, the head-to-body ratio will be 1: 5 (in an adult, 1: 8).
Incredibly, by 12 weeks, the baby even begins to move the arms and legs, trying to swallow and suck. But the mother still does not feel these movements, since the child is very small. With the help of ultrasound, baby's movements can be observed from the 8th week of pregnancy!
The sex of the child is determined at the time of conception, but the external genital organs are formed and are visualized only by 9-12 weeks, and quite precisely the sex of the child is determined already in the second trimester.
By the end of the trimester, the formation of the placenta ends. Now she takes over the functions of producing hormones and supporting the baby. The corpus luteum, which produced progesterone and estrogen in the 1st trimester, gradually loses its functions to it. Thanks to this, the mother ends with unpleasant toxicosis.
Critical days in the first trimester, when the risk of spontaneous abortion is highest, fall on 4-6, and then 8-12 weeks of pregnancy. In the first case, the threat of miscarriage is associated with improper implantation of the ovum into the uterus, in the second - due to an unfavorable hormonal background.
By the end of the trimester, the weight gain is 1.2-2 kg, the height of the bottom of the uterus is 10-11 cm. While the baby is building his body, his mother also undergoes global changes.
First, there is a restructuring of the whole organism, starting from the structure of the body (breast enlargement, uterine growth, weight gain), ending with the appearance of additional glands ("corpus luteum"). All this cannot but cause difficulties, the most famous of which is toxicosis.
Toxicosis is a characteristic phenomenon in the first trimester of pregnancy. Morning sickness, dizziness, weakness, even fainting conditions occur due to the fact that the corpus luteum, which is formed at the time of implantation of the ovum into the uterus, produces additional hormones progesterone and estrogen, which are necessary for the nutrition and development of the baby. But toxicosis is not at all in all women, this does not mean that the pregnancy is somehow going wrong.
The woman stops menstruating, although sometimes there may be a slight spotting. If the discharge becomes profuse and is accompanied by pain, you should immediately consult a doctor (this may be a sign of an incipient miscarriage).
In addition to toxicosis, a sign of the first trimester is the frequent urge to urinate due to the increasing pressure of the uterus on the bladder, breast enlargement and swelling, as well as its soreness, many women have veins.
On a psychological level, many women experience the first stress, mood swings, changes from a joyful-excited state to a depressive-depressed state. The expectant mother is irritable, may cry for no apparent reason, and often her sexual desire decreases. This is largely due to her fatigue from everything: from toxicosis, from work, from worries for the future baby, from worries about her new role - the role of a mother.
At the physical level, emotional changes are associated with hormonal changes and increased stress on the kidneys, liver, and pancreas. Usually by 13-14 weeks, this goes away with toxicosis.
The best recommendations are to think about yourself and relax more, exclude all possible reasons for stress from your life, walk, swim, breathe fresh air, and not sit in the office or at home. In extreme cases, take valerian, lemon balm, mint, and rosehip tea in limited quantities. If you feel that you cannot cope with yourself, do not hesitate and see a psychologist.
Until the 12th week, it is advisable for the expectant mother to register with the antenatal clinic. According to the plan, the first examination should take place at 8-10 weeks, in order to do the first ultrasound at 10-12 weeks and pass a double test to determine fetal malformations.
In the first trimester, the expectant mother takes the following tests:
- clinical blood test;
- blood biochemistry;
- general urine analysis;
- blood test for group and Rh factor, antibodies to Rh factor;
- a blood test for infections (toxoplasmosis, HIV, syphilis, rubella, parvovirus, hepatitis);
- gynecological smears for vaginal infections;
- examination by specialist doctors (endocrinologist, ophthalmologist, therapist, dentist, etc.);
- "double test" of blood for the level of hCG and plasma protein A in combination with ultrasound of the neck area (screening for congenital chromosomal developmental abnormalities, for example, Down's syndrome).
Conception - 1st trimester - 2nd trimester