The center for population research.
D000349:Africa; D001208:Asia; D001723:Birth Rate; D005060:Europe; D005193:Family Planning Services; D005260:Female; D006801:Humans; D007247:Infertility, Female; D007248:Infertility, Male; D008017:Life Expectancy; D008297:Male; D009316:National Institutes of Health (U.S.); D011153:Population; D012106:Research; D012109:Research Support as Topic; D014481:United States