956 Pregnancies complicated by any fetal anomaly are at increased risk for maternal morbidity and mortality

Abstract

Limited information exists regarding the impact of any fetal anomaly on maternal outcomes. We sought to determine if expectant management of a pregnancy complicated by fetal anomalies was an independent risk factor for severe maternal morbidity or mortality. This was a retrospective cohort study of the NICHD Consortium for Safe Labor (CSL) database. The exposure of interest was pregnancies complicated by any fetal anomaly. The outcome analyzed was a composite outcome of death, intensive care admission, pulmonary embolism, severe pre-eclampsia, eclampsia, or hysterectomy. Cases with missing information were excluded. After an unadjusted analysis, propensity scoring was utilized. Covariates were demographic factors, prior obstetric outcomes, and pre-existing medical comorbidities which would be available to clinicians at the time of second trimester fetal anatomy ultrasound assessment. Cases and controls were matched with preference given to exact matches. Sampling was done without replacement, and greedy match tolerance was within a probability of 0.1. Multivariable analysis was performed to adjust for propensity score. Of the 228,562 deliveries in the CSL database, 179,452 met inclusion criteria. 12,797(7.1%) were complicated by fetal anomalies, and 4510 (2.5%) we're complicated by the composite outcome. Fetal anomalies increase the relative risk of severe morbidity or mortality (RR 2.1 p<0.0001, 95%CI 1.94-2.28, NNH 39) in unadjusted analysis. Propensity scoring led to 7623 matched cases and controls, and pregnancies complicated by fetal anomalies increased the odds of the composite outcome (aOR 1.73 p<0.0001, 95%CI 1.44-2.07). Pregnancies complicated by any fetal anomaly nearly double the patient's underlying risk of severe maternal morbidity or mortality. This information should be utilized in shared decision-making at the time of prenatal diagnosis. Future studies should attempt to stratify patient risk based on the type and severity of the complicating fetal anomaly.