Unregistered obstetric patients: factor in perinatal losses in regionalized perinatal network.
D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007226:Infant Mortality; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000453:epidemiology; D009519:New York City; D011247:Pregnancy; D011248:Pregnancy Complications; D011295:Prenatal Care; D012306:Risk