The term of pregnancy can be determined in several ways. These methods are distinguished by their accuracy, convenience, accessibility for women. The exact period of gestation is extremely important for doctors, as it allows you to observe and make correct conclusions about the fetal development of the fetus. Determination of the gestational age is of great importance for the early detection of fetal development pathology, timely correction of pregnancy. By the time of gestation, doctors and a woman will know the date of birth of the baby.
The period of pregnancy can be accurately calculated by conception, by the first stirring of the fetus, by the first day of the last menstruation, etc.
By conception
Conception of the child occurs at the time of the fusion of the sperm and the egg, which should occur in the 1-2 days after ovulation in a woman. Many women learn about ovulation for the following symptoms: thick mucous discharge, tingling in the lower abdomen and in the region of the ovaries, an obvious sexual attraction. Other women use special tests for ovulation in contraceptive use to exclude unwanted pregnancies during ovulation days or vice versa, with the goal of conception. Some women determine basal temperature to learn about ovulation.
However, even if the day of conception is determined exactly, which is possible in a single sexual intercourse, doctors put a longer period of about 2 weeks. There is a misconception that this is due to the fact that the fruit is large, but it is not. Dimensions of embryos in early terms do not differ. And doctors calculate the obstetric term of gestation, from which they then repulse when determining the date of birth. In other words, the definition of pregnancy by conception is important and informative for the woman herself, but not for the doctor.
Obstetrical period
The obstetric period is determined in a different way and without taking into account the day of ovulation. In order to establish this period accurately, the doctor needs information about the first day of the last menstruation, and the duration of bleeding, in general, is not important. It is from the moment of the first day that the pregnancy begins counting. Therefore, it often turns out that the gestation period, determined by you for conception or for ovulation, differs from obstetric for a period of two weeks. Now this should not cause you any surprise.
Date of the first stirring
Usually, when determining the expected date of birth, the doctor follows the above-described obstetric gestation period, the ultrasound testimony in the early stages of pregnancy, and that is not unimportant, by the date of the first stirring of the fetus. The baby starts to feel primiparous women on the 20th week, rejuvenating much earlier - on the 18th week.
Ultrasound examinations
In the absence of pregnancy pathology, the first ultrasound is performed for 12-14 weeks, although this period is not suitable for an accurate determination of the gestation period. Intrauterine development of embryos is the same only during the first weeks after conception. Just in this period the doctor can set the gestation period to 1 day. Ultrasound examines the location of the fetus, palpitation, if any, etc. If the fetus lags behind in development according to the criteria of ultrasound or any deviations are detected, the studies are repeated after 7-10 days. Repeated ultrasound helps to identify a dead pregnancy in the early stages and other abnormalities.
The duration of pregnancy based on the results of ultrasound is more accurately determined in the early stages. Follow-up ultrasound at the 20th and 32nd weeks is accompanied by a refinement of the gestation period according to the size of the body parts and their proportions. Note that in the second half of pregnancy the fetus develops very individually. The norm is the birth of a baby on time with a weight of 2800-4000.
Visit the gynecologist
The first visit to a gynecologist by a future mother is always accompanied by an examination that should identify abnormalities and determine the gestational age, the location of the fetus in the case of an ectopic pregnancy. In the period of 5-6 weeks (delay of menstrual periods for 3-4 weeks) the uterus is increased slightly. In size it is comparable to a chicken egg, by 8 weeks - with a goose egg, at 10 weeks - with a female fist. At 12-14 weeks, the doctor can accurately determine the length of the uterus when viewed with a centimeter tape.