title: Neural-tube defects and mid-cycle abstinence: a test of the 'over-ripeness' hypothesis in man.
abstract: The prevalence of mid-cycle abstinence at the time of conception of infants born with neural-tube defects was found to be only 6-7 per cent (8/119) compared with that of 9-8 per cent (32/325) at the time of conception of non-affected siblings. This is suggestive evidence against mid-cycle abstinence--and, by inference, over-ripeness--as an important possible cause of neural-tube defects.
mesh_terms: D000022:Abortion, Spontaneous / Q000209:etiology; D000757:Anencephaly / Q000209:etiology*; D003268:Contraception Behavior; D005260:Female; D005306:Fertilization; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010060:Ovulation; D011247:Pregnancy; D012746:Sexual Abstinence; D012725:Sexual Behavior; D016136:Spina Bifida Occulta / Q000209:etiology*