Sex ratio in a sample of human fetuses in Denmark, 1962-1973.
The sex ratio was determined in 791 fetuses from pregnant women in the Copenhagen area 1962-1973. All the mothers were sterilized in connection with an induced abortion. Eighty percent of the fetuses had a crown-rump length between 50 mm and 150 mm corresponding to postmenstrual age of 11-19 weeks. The sex ratio was 138. There was no association between length and sex ratio. The difference between this sex ratio and that for live births in Denmark 1962-1973 (105-9) is substantial.
D000028:Abortion, Induced; D003718:Denmark; D004622:Embryo, Mammalian; D005260:Female; D005333:Fetus; D006801:Humans; D008297:Male; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012744:Sex Ratio