Obstetric calendar.
The midwifery calendar for establishing the gestation period begins on the first day of the last menstruation. Naturally, fertilization of the egg at this moment can not occur, as it is just beginning to ripen. Fertilization of the egg occurs at the time of ovulation (the release of the ovum from the ovaries), approximately two weeks after the end of the menstrual cycle (in many women the menstrual cycle is individual, and may be less or more). At the time of ovulation, conception occurs-the fertilization of the cell with a sperm cell. Therefore, the term of pregnancy usually begins two weeks later than the time set by the obstetrician-gynecologist.
Pregnancy in the midwife calendar is divided into weeks, months and trimester. In the week of 7 days, in the month of 4 weeks, or 28 days. The pregnancy lasts 40 weeks, this is 10 obstetric months. The entire duration of pregnancy is divided into trimesters: the first - from 0 to 12 weeks; the second - from 13 to 24 weeks, the third - from 25 to 40 weeks. Each trimester is characterized by its own characteristics.
- The first trimester of pregnancy (from 0 to 12 weeks).
The first trimester is characterized by a change in the hormonal background of a woman. The woman's body begins to prepare for pregnancy and its preservation, a large amount of progesterone, the female sex hormone, begins to be released. This hormone helps reduce the number of contractions of the muscles (soft tissues) of the uterus to protect the fetus. And since soft tissues are found in other organs, inhibition of muscle contractions occurs in them. Most often, the work of the gastrointestinal tract worsens, metabolism becomes worse, food is delayed in the body. This leads to nausea, vomiting, heartburn and even constipation. Also, the appearance of such unpleasant sensations can be facilitated by an increased tone of the vagus nerve. He departs from the brain and also inhibits the work of the gastrointestinal tract. All the unpleasant symptoms found on this term are called early toxicosis.
In this first trimester, the placenta begins to form. The placenta protects the woman from the loads from the fetal metabolism. Usually, after its formation, an early toxicosis passes.
In the first trimester, a woman needs to register with an obstetrician-gynecologist. This will help to identify ectopic pregnancy and the presence of possible diseases that need to be cured (infectious, hormonal disorders and others).
- Second trimester of pregnancy (from 13 to 24 weeks).
In this trimester, a lot of research is carried out related to the development and health of the child. An ultrasound (ultrasound) is performed, which shows the fetus's condition (its mass and height). It also shows the condition of the amniotic fluid, the fetal membranes and the tone of the uterus. Analyzes for hormones are carried out. In this trimester, it is possible to detect hereditary and chromosomal diseases (such as Down's disease), as well as various vices.
Complications in this trimester can be associated with a lack of oxygen (fetal hypoxia), usually a child begins to respond to it. The character of his movements changes, the frequency of heartbeats, hiccups appear. It is also possible the occurrence of iron deficiency anemia, bleeding and late miscarriage.
When identifying hypoxia, due to research, a special treatment is prescribed, which includes respiratory gymnastics. Such treatment is necessary especially in the second trimester, as the fetal brain develops intensively.
In this trimester, placenta formation ends, early toxicosis disappears, and there is no severity and shortness of breath in the third trimester. The woman begins to feel better. She has more time for her own affairs and herself, and she looks even better than before pregnancy.
The second trimester is the most convenient time to start attending courses for young parents. In such occupations, the father of the child may be present, who at the first minute of birth will be able to help the pregnant: in our time, the presence of the child's father is more frequent during childbirth. In this trimester, it is worth paying special attention to the choice of maternity home.
- Third trimester of pregnancy (from 25 to 40 weeks).
The beginning of the third trimester is calm, but as the baby grows, the load on the organs increases. Pressure on the diaphragm and heart increases, shortness of breath begins. Many women can also be disturbed by constipation, heartburn, hemorrhoids and frequent urination. Increases the load on the lower back and legs. There may be varicose veins, pain in the lower back.
In the third trimester, a woman should pay special attention to proper nutrition, and balance the order of exercise and good rest. It is worthwhile to follow the posture and choose a comfortable pose for sleep. If you follow these rules, you can avoid worry and pain.
When there are signs of childbirth, you need to calm down and go to the hospital.