Key points are not available for this paper at this time.
Summary The fetal biparietal diameter was measured by ultrasound during normal pregnancy. The range of biparietal diameter values for each week of pregnancy from 13 weeks until term (1029 measurements) was determined and longitudinal data (646 measurements) were used to illustrate the variation in growth rate according to fetal maturity, head size and weight.
Campbell et al. (Tue,) studied this question.