The Effect of Comprehensive Care on Maternal and Fetal Outcomes in Sickle Cell Disease Pregnancies

Patients with Sickle Cell Disease (SCD) have increased rates of maternal and fetal complications compared to the general population, including premature rupture of membranes, post-partum infection, low birth weight, small for gestational age (SGA), intrauterine growth retardation (IUGR) and preterm delivery. They also experience higher rates of antepartum complications: painful vasoocclusive crises (VOC), infections, PIH/preeclampsia, abruption, antepartum bleeding, cardiomyopathy, pulmonary hypertension, cerebral vein thrombosis, pneumonia, pyelonephritis, deep vein thrombosis (DVT), transfusion and systemic inflammatory response syndrome. Comprehensive care reduces morbidity and mortality in infancy and early childhood and is the cornerstone of care in SCD. However, the effect of comprehensive care on maternal and fetal outcome in patients with SCD has not been examined. We hypothesize that pre-conception comprehensive care improve maternal and fetal outcomes and reduced rates of antepartum complications in patients with SCD.

We conducted a retrospective review of patients with SCD (SS, SC, S/beta-thalassemia) who delivered at the Mount Sinai Hospital (MSH), a high risk obstetrics care institution in Central Ontario, Canada, between 2000 and 2010 based on the Antenatal Database, Delivery Database, electronic and paper-based medical records. Patients were jointly managed by a maternal-fetal medicine (MFM) specialist and hematologist specialized in hemoglobinopathies. We analyzed the maternal and fetal characteristics and outcomes (age at delivery, genotype, gravida, gestational age, birth weight, number of Caesarian sections and vaginal deliveries), antepartum complications (pregnancy induced hypertension (including pre-eclampsia and eclampsia), gestational diabetes mellitus, preterm premature rupture of membranes, oligohydramnios, abruption/previa, venous thromboembolism, urinary tract infection), and SCD-specific complications (painful vaso-occlusive crises, acute chest syndrome, pneumonia, and transfusion) based on the presence or absence of comprehensive care prior to pregnancy by the Red Blood Cell Disorders (RBCD) Clinic at the University Health Network, a SCD comprehensive care centre from the same catchment area as MSH. t-test was used to compare means of two groups, Fisher's exact test and chi-squared tests were used to compare categorical frequency data, where appropriate. Alpha value of 0.05 was chosen as the level of significance.

We identified 79 deliveries by 64 patients with SCD who received obstetric care at MSH. Mean gestational age at delivery was 37.69 weeks (95% CI 37.00 to 38.37 weeks) and 21 (27%) were preterm (< 37 weeks). Thirty-one deliveries (39%) were by Caesarian section and 48 were delivered vaginally. Seventeen (22%) were low birth weight (< 2500 g) and 11 (14%) were small for gestational age. Maternal and fetal outcomes and rates of antepartum complications were similar to the existing literature (Powars, 1986; Smith, 1996; Serjeant, 2004; Barfield, 2010). Twenty-eight deliveries by 22 of the 64 patients received comprehensive care at the RBCD clinic prior to their pregnancies for a mean duration of 5 years. There was no significant difference in maternal or fetal outcomes or antepartum complications. The results suggest that the role of comprehensive care prior to conception may not be as crucial in pregnancy outcomes of patients with SCD as previously thought. The lack of difference may also be due to the fact that the patients' care was closely monitored during the pregnancy by both specialists in hemoglobinopathies and high risk obstetrics. Limitations of the study include its single-centered and retrospective nature, exclusion of stillbirths and miscarriages, and small sample size. Also, patients who were enrolled in the comprehensive care program may carry more comorbidities and SCD-specific complications, compared to patients referred from the community, but this was not examined in the present study. Further prospective observational studies of SCD patients in the child-bearing age, with attention to the frequency and type of pre-pregnancy SCD-specific complications, as well as standardized application of comprehensive care, will be helpful in determining whether comprehensive care is useful in reducing antepartum complications in patients with SCD.

Kuo:Novartis Canada: Research Funding.