Association between in vitro fertilization and ischemic placental disease by gestational age.

Johnson, Katherine M; Hacker, Michele R; Thornton, Kim; Young, Brett C; Modest, Anna M

OBJECTIVE To evaluate the association between in vitro fertilization (IVF) and ischemic placental disease (IPD), stratified by gestational age. DESIGN We performed a secondary analysis of a retrospective cohort study of deliveries. SETTING Deliveries were performed over 15 years at a single tertiary hospital. PATIENT(S) We included all parturients who had a live born infant or an intrauterine fetal demise (IUFD). INTERVENTION(S) We compared pregnancies resulting from IVF cycles to non-IVF pregnancies. MAIN OUTCOME MEASURE(S) 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). RESULT(S) Of the 69,084 deliveries during the study period, 3,763 (5.4%) were conceived with IVF. The incidence of preterm delivery was 32.6% in IVF pregnancies and 10.8% in non-IVF pregnancies. Multiple gestations were more common in IVF pregnancies. Compared to non-IVF pregnancies, IVF pregnancies were more likely to develop both preterm and term IPD, even after adjustment for maternal age and parity. The risk of preterm IPD was 4 times higher (95% confidence interval, 3.7-4.4) in patients who underwent IVF compared with those who did not undergo IVF. Among parturients who delivered at ≥37 weeks of gestation, IVF pregnancies had 1.7 times the risk of term IPD (95% confidence interval, 1.6-1.9) compared with non-IVF pregnancies. CONCLUSION(S) IVF was strongly associated with preterm IPD. We found a similar, but attenuated, association between IVF and term IPD. The stronger association with preterm IPD suggests an association between IVF and placental insufficiency.