Objective: To estimate the effect of maternal heart disease on fetal growth and neonatal outcomes.
Methods: A retrospective cohort study of all women with congenital and acquired heart disease admitted at Chelsea and Westminster Hospital between 1994 and 2010 was performed. The women who delivered immediately before and immediately after each index pregnancy were used as controls. Data were obtained from medical and obstetric notes. Birth weight percentiles were calculated using a customized birth weight percentile program, and neonatal complications (preterm birth, perinatal mortality, and recurrence of congenital heart disease) were noted.
Results: Median birth weight percentile was significantly lower in the heart disease group (31) compared with the control group (49;P.001 Mann-Whitney U test [corrected].The rate of neonatal complications was significantly higher in the heart disease group (34% compared with 15%). Preterm birth occurred in 42 (13%) pregnancies, of which 67% were iatrogenic. Eighty-one (25%) newborns in the heart disease group were small for gestational age, and there were four stillbirths and four neonatal deaths (perinatal mortality rate 20 per 1,000).
Conclusion: This cohort study suggests a significant reduction in fetal growth rates associated with maternal heart disease, which is also associated with preterm delivery and reduced birth weight. The presence of maternal cyanosis and a reduced cardiac output are the most significant predictors.
Level of evidence: II.