Cardiac Risk Score to Predict Small for Gestational Age Infants in Pregnant Women With Heart Disease

Abstract

BackgroundOne of the most common fetal complications in pregnant women with cardiovascular disease is a small for gestational age (SGA) neonate, which is associated with a higher risk of perinatal morbidity/mortality and poor long-term health outcomes. The objective of this study was to identify cardiac determinants and derive a risk score for clinically relevant SGA < 5th percentile (SGA-5th). MethodsA prospective cohort of 1812 pregnancies in women with heart disease were studied. SGA-5th was the outcome of interest, defined as birth weight < 5th percentile for gestational age and sex. Multivariable logistic regression analysis was used to identify predictors for SGA-5th. Based on the regression coefficients, a weighted risk score was created. ResultsSGA-5th complicated 10% of pregnancies, 11 predictors of SGA-5th were identified, and each was assigned a weighted score: maternal cyanosis (8), Fontan palliation (7), smoking (3), moderate or severe valvular regurgitation (3), β-blocker use throughout pregnancy (4) or only in the 2nd and 3rd trimesters (2), high baseline β-blocker dose (4), body mass index < 18.5 kg/m2 (3) or 18.5-24.9 kg/m2 (1), Asian/other ethnicity (2), and significant outflow tract obstruction (1). In the absence of these identified risk factors, the risk of SGA-5th was approximately 4%. Pregnancies with risk scores of 1 had a rate of 5%; 2, 7%; 3, 9%; 4, 12%; 5, 14%; 6, 18%; 7, 23%; 8, 28%; and ≥ 9, 34%. ConclusionsThere are a number of cardiac predictors that are associated with increased risk of SGA-5th. This is a prognostically important outcome, and consideration should be given to routinely predicting and modifying the risk whenever possible.