Maternal anti-D prophylaxis during pregnancy and risk of hemolysis among preterm infants.

Objective: To evaluate whether Rh-positive preterm newborn infants born to Rh-negative mothers treated with prophylactic anti-D immunoglobulins exhibited signs of hemolytic reaction, including anemia and hyperbilirubinemia.

Study Design: Retrospective data were collected for 94 Rh-positive preterm newborns born at gestational age (GA) 28 to 34 weeks to 76 Rh-negative mothers and for matched controls.

Result: We found 11.7% positive Coombs' tests among infants in the study group and slightly higher bilirubin levels at birth and on the following 3 days. No differences were recorded between the study and the control groups for hematocrit levels throughout hospitalization, maximal bilirubin level, phototherapy treatment or the need for blood transfusion.

Conclusion: Among preterm Rh-positive newborn infants born to Rh-negative mothers, there appears to be no evidence of significant hemolytic reaction derived from placental anti-D transfer. Further prospective studies are needed to confirm these findings in order to support anti-D administration close to preterm birth.