Preeclampsia acts differently in in vitro fertilization versus spontaneous twins

To investigate risk factors and pregnancy outcome of spontaneous vs in-vitro fertilization (IVF) twins complicated with preeclampsia. A retrospective population-based cohort study comparing maternal and neonatal outcome in IVF vs spontaneously conceived twins was conducted. Deliveries occurred in a tertiary medical center between the years 1988 and 2010. Women who conceived after ovulation induction and those with chronic hypertension were excluded from the study. Multiple logistic regression models were used to control for confounders. The study population included 4428 twin pregnancies, of these 314 (7.1%) had preeclampsia; 64 (20.3%) were IVF twins and 250 (79.7%) were spontaneous twins. Preeclampsia was more common in IVF compare to spontaneous twins (13.8 vs 7.6%, OR = 1.81, CI = 1.50–2.17, P