Letter: Birth control and genetic changes in Chile.
D000757:Anencephaly / Q000453:epidemiology; D002677:Chile; D005193:Family Planning Services; D005260:Female; D005313:Fetal Death / Q000235:genetics; D006801:Humans; D008297:Male; D011247:Pregnancy; D012744:Sex Ratio; D014798:Vital Statistics