Effects of grandparental and parental age, birth order, and geographic variation on the sex ratio of live-born and stillborn infants.
D000328:Adult; D000367:Age Factors; D000368:Aged; D000704:Analysis of Variance; D001722:Birth Order; D005190:Family; D005260:Female; D005313:Fetal Death / Q000453:epidemiology*; D005843:Geography; D006801:Humans; D007558:Italy; D008297:Male; D008423:Maternal Age; D008875:Middle Aged; D010290:Parents; D011247:Pregnancy; D012744:Sex Ratio; D012959:Socioeconomic Factors