Anencephaly in Japan: paternal age, maternal age and birth order.
The statistical association between incidence of anencephaly and paternal age, maternal age and birth order was analysed in 1815 cases of foetal deaths with anencephaly reported during 1975--6. The birth order association was confirmed with an extremely high degree of statistical significance.
D000293:Adolescent; D000328:Adult; D000757:Anencephaly / Q000453:epidemiology / Q000235:genetics*; D001722:Birth Order; D005260:Female; D005313:Fetal Death / Q000453:epidemiology; D006801:Humans; D007086:Illegitimacy; D007564:Japan; D008297:Male; D008423:Maternal Age; D008954:Models, Biological; D010331:Paternal Age; D011247:Pregnancy; D012044:Regression Analysis; D012306:Risk