To determine the gestational age can be approximated to focus on increasing the size of the uterus and its location in the pelvic cavity and abdominal cavity at 12 weeks of pregnancy the uterus is located at the upper edge of the symphysis pubis in 16 weeks - midway between the symphysis pubis and the umbilicus, at 20 weeks - at the level of the navel. At 28 weeks, the uterus is located midway between the umbilicus and the xiphoid process of the sternum, at 32 weeks she is at the highest level - reaches the sternum and rib extends beyond the arc, and then the fetal head is firmly pressed to the entrance of the pelvis and the height of standing uterus slightly decreases.
Roughly determine the gestational age and can be active at the beginning of feeling fetal movements - at first pregnancy, women begin to feel the movement of the child at 19-20 weeks of pregnancy, and women who are hatching a second (third, etc.) of the child can feel it for 2 weeks earlier. But this method of determining the duration of pregnancy is very inaccurate, because it is often a woman can not always accurately assess the activity of the child.
The most reliable way to determine the gestational age at the moment is an ultrasound. Just focusing on the size of the bones of the child, the results of measuring the size of the head, the degree of maturity of the placenta can determine the actual length of pregnancy with any of her time. This research can be conducted in any stage of pregnancy, because it does not threaten the mother and her unborn child are no complications. This method allows to determine the presence of pregnancy at the early timing, and monitor its development at any time.
To accurately determine the duration of pregnancy in women should focus on the combination of all these parameters, as in the case of significant differences in terms of the possibility of complications, and the definition of pregnancy to help prevent them.