Maternal clinical disease characteristics and maternal and neonatal outcomes in twin and singleton pregnancies with severe preeclampsia.

Objective: Based on anecdotal observations, there is concern that severe preeclampsia leads to greater morbidity and mortality for mothers and neonates of twin pregnancies than for mothers and neonates of singleton pregnancies. Because few studies have been done, this study compared maternal disease characteristics and maternal/neonatal clinical outcomes of twin and singleton pregnancies complicated by severe preeclampsia.

Study Design: An historical cohort study of patients hospitalized at the Mount Sinai Hospital in New York City, NY, USA, from 2006 to 2010, compared 63 twin and 339 singleton pregnancies complicated by severe preeclampsia via chart review. Women were analyzed in two groups: hospitalized ≤34 weeks gestational age (GA) and hospitalized >34 weeks GA. Univariable analysis (using Chi-square test, Fisher's Exact test, Student's t-test, or Wilcoxon Rank-Sum test, as appropriate) then multivariable analysis (using multivariable linear regression or multivariable logistic regression, as appropriate) compared maternal disease characteristics and maternal/neonatal clinical outcomes in twin and singleton pregnancies.

Results: Women with twins were older [mean age 34.9 years (standard deviation (SD) 7.9 years) vs. 29.4 years (SD 7.4 years), P-value<.001] and women with singletons had a higher prevalence of chronic hypertension (21% vs. 8%, P=.02) and higher prevalence of history of preeclampsia (13% vs. 2%, P=.006). Women with twins were admitted for severe preeclampsia at an earlier gestational age (GA) [median twin 34.9 weeks GA (interquartile range, IQR, 32.7, 36.1) vs. median singleton 37.1 weeks GA (IQR 35.0, 38.9), P<.001]. Among women presenting ≤34 weeks GA (27 twins; 108 singletons), women with singletons had a higher mean systolic blood pressure (BP) (181.1 vs. 163.5, P<.001), higher mean diastolic BP (108.4 vs. 100.1, P=.002), and higher prevalence of headache (56% vs. 30%, P=.02). Among women presenting >34 weeks GA (36 twins; 231 singletons), women with singletons had a higher prevalence of headache (54% vs. 28%, P=.004).

Conclusion: Mothers and neonates of twin pregnancies complicated by severe preeclampsia do not appear to have greater morbidity and mortality compared to mothers and neonates of singleton pregnancies complicated by severe preeclampsia.