title: Variation of primary and secondary mammalian sex ratio.
authors.forename: M E
authors.initials: ME
authors.lastname: Bernstein
mesh_terms: D000022:Abortion, Spontaneous / Q000453:epidemiology*; D000818:Animals; D005260:Female; D006801:Humans; D007315:Insemination, Artificial; D008297:Male; D011247:Pregnancy; D012744:Sex Ratio; D013094:Spermatozoa / Q000032:analysis*