Maternal age and spina bifida: longitudinal versus cross-sectional analysis.
D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008423:Maternal Age; D009518:New York; D011247:Pregnancy; D011336:Probability; D016135:Spinal Dysraphism / Q000453:epidemiology*