Diminished ovarian reserve is a risk factor for preeclampsia and placental malperfusion lesions

To assess obstetric outcomes and placental findings in pregnancies attained by in vitro fertilization (IVF) in patients with diminished ovarian reserve (DOR).Retrospective cohort study.University-affiliated tertiary hospital.DOR, defined as an antral follicle count (AFC) of 6 or less (DOR group), compared with patients with no DOR and an antral count above 6 (control group).Live singleton births after IVF between 2009 and 2017.Primary outcomes were placental findings, including anatomic, inflammatory, vascular malperfusion, and villous maturation lesions, as categorized according to the Amsterdam Placental Workshop Group Consensus. Secondary outcomes included obstetric and perinatal outcomes.A total of 110 deliveries of patients with DOR were compared with 772 controls. Maternal age was higher in the DOR group than in the control group (36.3 ± 4.4 years vs. 35.3 ± 4.1 years, P=.02). Patients with DOR were more likely to have a diagnosis of endometriosis (P=.02) and less likely to have a diagnosis of male factor (P<.001), ovulation disorder (P<.001), or tubal factor (P=.04), or a transfer of a blastocyte (P=.007). After adjustment for confounders, pregnancies in the DOR group were notable for a significantly higher rate of preeclampsia (8.1% vs. 2.7%, adjusted odds ratio: 3.05, 95% confidence interval: 1.33-6.97). On placental examination, DOR was associated with a higher rate of fetal vasculopathy (P=.01) and multiple fetal vascular malperfusion lesions (P=.03), and a lower rate of circummarginate insertion (P=.01) and intervillous thrombosis (P=.02).DOR, specifically defined as an AFC of 6 or less, is associated with a higher incidence of preeclampsia and multiple placental fetal vascular lesions.