Premature births.
D000293:Adolescent; D000328:Adult; D005260:Female; D005313:Fetal Death / Q000209:etiology; D006801:Humans; D007182:Income; D007231:Infant, Newborn; D007234:Infant, Premature; D008423:Maternal Age; D008428:Maternal Mortality; D007744:Obstetric Labor Complications / Q000453:epidemiology; D007752:Obstetric Labor, Premature / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality; D010298:Parity; D011247:Pregnancy; D011295:Prenatal Care; D013997:Time Factors