Poverty as a criterion of risk.
D000293:Adolescent; D000328:Adult; D001741:Black or African American; D001722:Birth Order; D001724:Birth Weight; D002657:Child Development; D005006:Ethnicity; D005193:Family Planning Services; D005260:Female; D005313:Fetal Death / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007226:Infant Mortality; D007231:Infant, Newborn; D007234:Infant, Premature; D008423:Maternal Age; D008428:Maternal Mortality; D010298:Parity; D010414:Pennsylvania; D011203:Poverty; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology / Q000209:etiology*; D011647:Puerto Rico; D012959:Socioeconomic Factors; D014481:United States