Maternal age and Down's syndrome. The shift of affected infants to younger mothers in Hokkaido.
D000328:Adult; D004314:Down Syndrome / Q000235:genetics; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007564:Japan; D008423:Maternal Age; D011247:Pregnancy; D014178:Translocation, Genetic