Sickle cell disease and increased adverse maternal and perinatal outcomes in different genotypes.

BACKGROUND: Sickle cell disease (SCD) comprises a heterogeneous group of inherited hemolytic disorders that increases the risk of maternal and perinatal complications due to chronic systemic inflammatory response, endothelial damage and vaso-occlusion. The contribution of genotypes to the severity of outcomes during pregnancy is not completely established.

METHODS: A retrospective study of medical charts was performed to compare maternal and perinatal outcomes in Hb SS, Hb SC disease and sickle-beta thalassemia (Hb Sβ) pregnancies followed at a high-risk antenatal care unit over a 6-year period. A descriptive analysis of morphological findings was performed of the placenta when pathology reports were available.

RESULTS: Sixty-two SCD pregnant women [25 Hb SS (40 %), 29 Hb SC (47 %) and 8 Hb Sβ (13 %)] were included. Overall, SCD was associated with maternal complications (77 %), preterm birth (30 %), cesarean section (80 %) and a need of blood transfusion. In general there were no statistically significant differences between genotypes. The only significant difference was the hemoglobin level at first antenatal care visit which was lower for the homozygous genotype (7.7 g/dL) compared to Hb SC and Hb Sβ (9.7 g/dL and 8.4 g/dL, respectively; p-value = 0.01). Ten of 15 evaluated placentas showed abnormal morphological findings CONCLUSION: SCD, regardless of the underlying genotype, is associated with increased adverse maternal and perinatal outcomes and placental abnormalities associated with maternal vascular malperfusion.