AUTOIMMUNE HEMOLYTIC ANEMIA DURING PREGNANCY AND PUERPERIUM: AN INTERNATIONAL MULTI-CENTER EXPERIENCE.

Relapsing or occurring de novo autoimmune hemolytic anemia (AIHA) during pregnancy or puerperium is a poorly described condition. Here we report 45 pregnancies occurring in 33 women evaluated at 12 centers from 1997 to 2022. Among the 20 women with AIHA diagnosis before pregnancy, 10 had a relapse. Additional 13 patients developed de novo AIHA during gestation/puerperium (two patients had AIHA relapse during a second pregnancy). Among 24 hemolytic events, anemia was uniformly severe (median Hb 6.4 g/dL, range 3.1-8.7) and required treatment in all cases (96% steroids +/- intravenous immunoglobulin, IVIG, 58% transfusions). The response was achieved in all cases and was complete in 65% of cases. Antithrombotic prophylaxis was administered in eight patients (33%). Rituximab was administered in four patients, and cyclosporine was added in one after delivery. The rate of maternal complications was 15%, including premature rupture of membranes, placental detachment, and preeclampsia. Early miscarriages occurred in 13% of pregnancies. Fetal adverse events (22% of cases) included respiratory distress, fetal growth restriction, preterm birth, AIHA of the newborn, and two perinatal deaths. In conclusion, the occurrence of AIHA does not preclude the ability to carry a healthy pregnancy, provided close monitoring, prompt therapy, and awareness of potential maternal and fetal complications.