Prenatal sex ratio in man. Observations contradictory to the prevailing concept.
D000653:Amniotic Fluid / Q000166:cytology; D004622:Embryo, Mammalian; D005260:Female; D005835:Genitalia / Q000196:embryology; D006066:Gonads / Q000033:anatomy & histology; D006801:Humans; D008297:Male; D011247:Pregnancy; D012728:Sex Chromatin; D012732:Sex Determination Analysis; D012744:Sex Ratio