713: The association between in vitro fertilization and ischemic placental disease by gestational age

Conditions of ischemic placental disease (IPD)—preeclampsia, abruption, and intrauterine growth restriction (IUGR)—more often occur together when they occur in the preterm period, suggesting a common pathophysiologic mechanism for IPD at preterm gestations. In vitro fertilization (IVF) is associated with IPD, though the mechanism is unclear. We evaluated the effect of gestational age on the association between IVF and IPD and hypothesized that IVF would be more strongly associated with preterm IPD than term IPD. The cohort included deliveries from 2000 to 2015 at a tertiary hospital. We used data from an affiliated infertility treatment center and birth certificates to determine if the pregnancy was due to IVF or spontaneous (non-IVF). The primary outcomes were preterm and term IPD (preeclampsia, placental abruption, small-for-gestational age infant (SGA), or an intrauterine fetal demise (IUFD) due to placental insufficiency). We defined SGA as <10thpercentile using U.S. growth curves and preterm as <37 weeks’ gestation at delivery. We used log-binomial regression to estimate risk ratios (RR) and 95% confidence intervals (CI), adjusted for maternal age and/or parity. Of the 69,084 deliveries, 3,763 (5.4%) were IVF pregnancies. The incidence of preterm delivery was 32.6% in IVF pregnancies and 10.8% in non-IVF pregnancies. Compared to non-IVF pregnancies, IVF pregnancies were more likely to develop IPD/IUFD due to placental insufficiency. The effect was stronger for preterm deliveries (RR: 4.0; 95% CI: 3.7-4.4) than term deliveries (RR: 1.7; 95% CI: 1.6-1.9). IVF pregnancies had a higher risk of each component of IPD,and the risks were stronger in the preterm period (Table). The cumulative incidence of IPD was higher for IVF pregnancies at every gestational age (Figure). Figure caption: Cumulative incidence of IPD/IUFD due to placental insufficiency by gestational age, comparing pregnancies conceived with IVF (upper blue line) to those that were not conceived with IVF (lower red line) Pregnancies conceived with IVF are at higher risk of IPD/IUFD due to placental insufficiency in the preterm period than in the term period. These findings support the hypothesis that IVF is associated with placental insufficiency.View Large Image Figure ViewerDownload Hi-res image Download (PPT)