Greater female communalities in prenatal hand and dental development.

As shown in 15 male and 17 female developmentally-normal, 6-9 week (15-47 mm crown-rump length) embryos, intercorrelations (communalities) involving both mesial and distal deciduous teeth and proximal and distal segments of the developing hand were systematically higher in female embryos than in male embryos, without exception, a finding in surprising accordance with postnatal dimensional and temporal development of the dentition and of the appendicular skeleton.