title: Mongolism, delayed fertilization and human sexual behaviour.
mesh_terms: D000328:Adult; D000367:Age Factors; D004314:Down Syndrome / Q000209:etiology*; D005260:Female; D005306:Fertilization; D006801:Humans; D008297:Male; D008423:Maternal Age; D010063:Ovum; D012725:Sexual Behavior