Adipose tissue growth patterns during human gestation: a histometric comparison of buccal and gluteal fat depots

Morphometric analysis of fat lobule size and number, and fat cell number in middle buccal and gluteal fat depots during the prenatal period was carried out using histological sections from 88 typical-for-age or normal human prenates of both sexes. The sample ranged from 110 to 385 mm Crown-Rump length (or from 14 through 42 gestational weeks). Compared with the buccal fat pad, the gluteal fat was one to four weeks delayed in lobule maturation. In addition to fat maturation differences between buccal and gluteal fat sites, gluteal fat characteristically showed fewer but larger fat lobules than did the buccal fat pad. Conversely there appeared a larger number of fat cells per unit area in the buccal fat than in the gluteal fat. Fat accumulation in human buccal and gluteal fat depots include differences in growth timing and magnitude, but also different developmental patterns. These patterns suggests our hypothesis that while lobule hyperplasia and hypertrophy occur at both sites, gluteal fat lobules grow primarily through lobule hypertrophy whereas the buccal fetal pad grows through lobule hyperplasia.