Determining the estimated time of birth of a baby causes difficulties not only for the expectant mother, but, at times, for the doctor. When calculating the date of birth, obstetricians-gynecologists rely on several indicators.
Instructions
Step 1
Try to determine when your baby is born by the date of your last period. Add 280 days to its first day. The resulting number may become the date of birth of your baby. But it should be borne in mind that in this way you can determine the time of birth only if you have a regular menstrual cycle lasting 28 days. If the cycle is less, then childbirth can be earlier and, conversely, if more - later.
Step 2
The next way to determine the date of birth is the ultrasound results. During the study, the doctor, using special tables, determines the correspondence between the size of the fetus and the duration of pregnancy. On the first ultrasound, more accurate results are given. In late pregnancy, the size of the fetus fluctuates, so it is difficult to determine the exact date of birth. Sometimes the doctor can determine a shorter pregnancy period by ultrasound. This is sometimes associated with intrauterine growth retardation of the fetus.
Step 3
In addition, you can calculate when the baby is born from the date of its first stirring. If you will be giving birth for the first time, add 20 weeks to this date. If you have already had childbirth - 22 weeks. But this method is not objective, since a woman can take intestinal peristalsis for moving the crumbs. Or, on the contrary, for a long time to take the movement of the child for the processes in the internal organs. In addition, many pregnant women feel the first movement in the early stages - at 15-16 weeks.
Step 4
The doctor will be able to determine the exact date of your baby's arrival when examining you in a chair. If the first visit to the antenatal clinic was up to 12 weeks, then the doctor will tell you the exact duration of pregnancy and the expected date of birth by the size of the uterus. Remember that the date of birth depends on the individual characteristics of your body and on the readiness of the baby to be born. Don't worry if labor doesn't start on the expected day. A normal pregnancy lasts 38 to 42 weeks.
