How to determine how many weeks of pregnancy?
During the first visit to the pregnant woman, the gynecologistdetermines the preliminary date of birth using the Naegele formula. To set the due date, he uses a special obstetric calendar, but a woman can make simple calculations on her own.
Using the calendar, week of pregnancydetermined by the formula Negele Photo: GettyTo find out when the pregnancy began, it is necessary to add 7 days to the first day of the last month and take 3 months. 40 weeks are counted from the received date - this will be the preliminary day of delivery. It is important! The obstetric method is far from accurate, especially for women with an irregular menstrual cycle. It is easier for women to keep a monthly calendar for calculating the onset of pregnancy by the embryonic method. The probability of conceiving a child is highest during ovulation. It is possible to determine this favorable period for fertilization by deducting two weeks from the beginning of the last menstrual period. The errors in determining the week of gestation by the date of ovulation are related to the fact that it is likely, though less likely, to conceive a child on other days of the menstrual cycle.
Medical methods to help determine the week of pregnancy
Over the course of 9 months, a woman goes through threeplanned ultrasounds: at 10-14, 20-24 and 32-34 weeks. The examinations help to promptly identify fetal malformations and monitor the course of pregnancy. The tasks of obstetric ultrasound scanning also include specifying the week of pregnancy. The first ultrasound is of particular value for gynecologists in this regard, as it provides the most accurate information.
It is relatively accurate to determine the week of pregnancy with an Ultrasound Photograph: Getty The age of the fetus is determined by the diagnostician by measuring:
- child's head size;
- distance from coccyx to crown;
- the diameter of the chest;
- abdominal circumference;
- thigh length
Comparing the obtained data and average values,indicated in the table, the doctor determines the week of pregnancy. During the examination, the gynecologist can determine the period by the size of the uterus. This is easiest to do at the beginning of pregnancy: in the fourth week, the female organ is the size of a chicken egg, in the eighth week - a goose egg. The first movement of the fetus is also important for determining the period. Women feel the movements of the first child from the 20th week, the next children - from the 18th. So, the pregnancy period is calculated by the date of the beginning of the last menstruation. More accurate data is given by the first ultrasound examination, carried out in the third month. Read about
