What is the average biparietal diameter (BPD) during pregnancy?

The average biparietal diameter (BPD) during pregnancy is approximately 9.5 cm, particularly around 34 to 36 weeks of gestation. The BPD is an important measurement taken during obstetric ultrasounds to assess fetal growth and development. It refers to the distance between the two parietal bones of the fetal skull and provides information about the fetal head size, which can be useful in estimating gestational age and detecting potential anomalies.

Accurate measurements of the BPD are crucial because they contribute to overall fetal biometry assessments, which help determine the appropriate management of the pregnancy. Moreover, as the fetus continues to grow, the BPD tends to increase, so understanding the average value for different gestational ages is important for monitoring fetal health.

The average of 9.5 cm reflects the growth trends established through clinical data, making it the most reliable figure to use when considering typical fetal development during late pregnancy.