Towards zero mortality in sickle cell pregnancy: A prospective study comparing haemoglobin SS and AA women in Lagos, Nigeria

Abstract

Introduction: Sickle cell disease in pregnancy carries increased risk of maternal and perinatal morbidity and mortality. Past studies on pregnancy complications in sickle cell disease women were limited by relatively small sample sizes, and use of retrospective and hospital discharge data.

Study design: This prospective case-control study compared booked pregnant Haemoglobin (Hb) SS women with AA controls from two tertiary centres in Lagos, in order to precisely identify their complication and mortality rates and identify associated factors. Eligible pregnant HbSS and HbAA women were recruited from antenatal clinics at booking and follow-up visits. Information was collected on a proforma and data was analyzed using IBM SPSS version 20.

Results: We found higher complication rate in HbSS group, commonest complications being vaso-occlusive crisis (RR 1.47, 95% CI 1.22 - 1.78), pregnancy induced hypertension (RR 1.31, 95% CI 1.08 - 1.57), urinary tract infection (RR 1.32, 95% CI 1.12 - 1.57), and intrauterine growth restriction (RR 1.2, 95% CI 1.05 - 1.34). HbSS group had higher systolic and mean arterial blood pressure values in early puerperium compared to HbAA group (p = 0.014 and 0.024 respectively). No maternal death recorded in both group. Incidence of low birth weight <2.5Kg was 38% in HbSS and 4% in HbAA subjects, p = 0.001. However, overall maternal and perinatal outcomes were comparable in both groups (p = 1.000).

Conclusion: Although sickle cell disease poses higher obstetric risk in pregnancy, maternal and perinatal outcome can be as good as in the non-sickle cell pregnant women if adequate and prompt individualized care is given to this group of women.

Keywords: Complications; haemoglobin AA; haemoglobin SS; maternal outcome; perinatal outcome; sickle cell disease pregnancy.