During pregnancy, it is common to check the biparietal diameter of the fetus during prenatal examinations, which is beneficial for understanding the development of the fetus. However, when a pregnant woman at 37 weeks of gestation checks her biparietal diameter, the result shows that it is 98mm. Is this considered long?
Generally speaking, the average biparietal diameter of a fetus at 37 weeks of gestation is about 90mm, with an error of no more than 6.3mm. Therefore, the biparietal diameter of a fetus detected at 37 weeks of gestation is 98mm, which is slightly longer. This length is mostly around 39 or 40 weeks of gestation, but due to individual developmental differences, it is not surprising that some fetuses have a longer biparietal diameter than the average fetus.
The biparietal diameter of the fetus is actually the widest length of the fetal head horizontally from left to right, which may be called the greater transverse diameter of the head. Usually, checking the biparietal diameter of the fetus during pregnancy is to examine the development of the fetus, see if the head is symmetrical, and also serve as a reference for whether the pregnant woman can give birth naturally. Sometimes, it can even be used as a reference data for fetal weight estimation.
In general, the narrowest part of a woman's pelvis is about 100mm, which is the widest distance allowed for the fetus to pass through. When the biparietal diameter of the fetus approaches 100mm, doctors will advise women not to choose vaginal delivery during labor because the fetus may face significant obstacles during delivery. Therefore, it is generally recommended that women choose cesarean section.
