Assisted Reproductive Technology And Stillbirth Risk: Selected States, 2006-2011

INTRODUCTION: To examine trends and characteristics of stillbirths among pregnancies (live births and stillbirths) following assisted reproductive technology (ART) and to evaluate the association between ART and risk of stillbirth using linked ART surveillance and vital records from Connecticut, Florida, Massachusetts, and Michigan. METHODS: We examined trends of stillbirth rate (number of stillbirths/1,000 live births and stillbirths) and estimated the adjusted risk ratios (aRR) for associations between ART and stillbirth (adjusting for maternal characteristics, pregnancy history, and pre-pregnancy medical conditions), stratified by plurality and gestational age (<28 and >28 weeks). We also used ICD-10 to examine causes of stillbirth. RESULTS: During 2006–2011, 282 ART stillbirths and 15,540 non-ART stillbirths were identified. ART stillbirth rates were lower than the non-ART stillbirth rates for both singleton (3.1 versus 6.0) and multifetal pregnancies (9.4 versus 18.3). At <28 weeks, the risk of stillbirth among ART-pregnancies was significantly lower than for non-ART pregnancies, aRR 0.38, 95% confidence interval (CI) 0.22–0.65 among singletons and aRR 0.63, 95% CI 0.42–0.94 among multiples. The leading causes of stillbirth were similar for both ART and non-ART pregnancies; maternal conditions (16.6%) (eg, hypertensive disorders, infections, respiratory diseases, periodontal diseases, incompetent cervix, etc), followed by placental abnormalities (9.8%), umbilical cord conditions (9.2%), chorioamnionitis (3.8%), and low birth weight (2.7%). CONCLUSION: ART was associated with a decreased stillbirth risk prior to 28 weeks of gestation. Earlier detection and management of fetal and maternal conditions among ART-conceived pregnancies may explain the lower rates of early fetal death observed in this study.