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Birth characteristics, as reported on birth certificates, were compared in 498 Black children with sickle cell trait and 498 Black children with normal hemoglobin matched on sex and month of birth. All had participated in a voluntary sickle cell screening program in New York State (exclusive of New York City); mean age at screening was 6.4 years for both groups. Cases and controls did not differ signifi­cantly in mean birth weight, frequency of “low” birth weight, mean maternal and paternal age, frequency of birth defects, fertility of mothers, and frequency of most complications of pregnancy and labor. The higher frequency of abruptio placentae (relative risk, 3.0) and specified types of dystocia (relative risk, 2.6) in cases than in controls suggested the need for further studies.