How can we calculate the gestational age by weeks and months
Not all women know how to correctly calculate the duration of pregnancy. Weekly - this is the most common method of calculation among gynecologists. Such a calculation is most convenient for the conduct of pregnancy, as well as to find out about the expected date of birth (DA). Each woman individually proceeds pregnancy. Date of birth is therefore appointed only approximately, since the child can not be born on a certain day and hour.
What factors affect the calculation of DA
It is believed that pregnancy should last 40 weeks, but doctors warn that the baby is fully formed by week 38 and can be born at any time. A child may be born before the DA with a woman carrying a large fetus (more than 4 kg), its low location, as well as with multiple pregnancies. It does not matter that in the fortieth week the baby was not born.He can be born on the 41st or 42nd week, it is considered the norm. If, on the 42nd week of pregnancy, the woman has not given birth, then she should contact her gynecologist, or better, go to the maternity hospital right away. If necessary, doctors will cause contractions with the help of special preparations.
Calculate the duration of pregnancy
So, one of the main tasks of a gynecologist and a pregnant woman is to calculate the duration of pregnancy. Weekly the gynecologist calculates the term, focusing on the date of the beginning (or end) of the last menstrual period, but it also happens that the pregnant woman called this date incorrectly, respectively, the gynecologist's assumptions about how the pregnancy proceeds, and what period it may be wrong. In this case, it is possible to calculate the gestational age by weeks or months and you can calculate the DA. There are many ways to do this:
- When calculating the period by months, pregnancy should last about 9 months (plus or minus 1 week) from the end of the last month. According to obstetric calculations, the gestation period is about 10 months, since gynecologists consider him to be based on the date of the last month before the pregnancy.In this case, the months are called lunar and are considered in accordance with the lunar cycle (28 days). That is, a woman should give birth in about 280 days.
- One of the easiest ways to know and calculate the gestation by weeks is to go for an ultrasound scan. However, the apparatus allows for a certain error: on small terms it can be miscalculated in days, and on large ones - in weeks.This is because the ultrasound examines the duration of pregnancy according to general parameters (height, weight, etc.), but these data are individual for each child.
- There is also a special calendar used by obstetrician-gynecologists. In this case, the account is kept weekly from the date of commencement of the last menstruation until the day of contacting the antenatal clinic. In this case, as already mentioned, the DA will fall between 38-41 weeks from the beginning of the last menstrual period.
- Regular examination by a gynecologist is also one of the ways to determine the duration of pregnancy. In the first trimester, the doctor determines the term by the size of the uterus, and then - by its distance from the navel.