The impact of newborn gender on the placental histopathology and perinatal outcome in singleton live births resulting from in vitro fertilization treatment

Abstract Research Question Does the newborn gender have an impact on the placental histopathology pattern and perinatal outcome in singleton live births following in vitro fertilization treatment? Design Retrospective cohort study evaluating data of all live births from one academic tertiary hospital following in vitro fertilization treatment during the period from 2009 to 2017. All patients had placentas sent for pathological evaluation irrelevant of maternal and fetal complications status. The exclusion criteria were abnormal uterine cavity findings, previous uterine surgery, in vitro maturation cycles, preimplantation genetic diagnosis cycles, and multiple pregnancies. The primary outcomes included anatomical, inflammation, vascular malperfusion and villous maturation placental features. The secondary outcomes included fetal, maternal, perinatal and delivery complications. To adjust our results for factors potentially associated with placental pathology features we conducted a multivariate analysis. Results A total of 1057 live births were included in the final analysis and were allocated to the study groups according to the fetal gender: males (n=527) and females (n=530). After the adjustment for potential confounding factors, male gender was significantly associated with villous agglutination (OR 9.8; 95% CI 1.4–78.2), avascular villi (OR 4.1; 95% CI 1.3–12.6), and maternal vascular malperfusion (OR 1.8; 95% CI 1.2–2.7). Female gender was significantly associated with bilobed placenta (OR 0.2; 95% CI 0.06–0.8) and subchorionic thrombi (OR 0.5; 95% CI 0.3–0.9). The prevalence of adverse fetal, maternal, and delivery outcomes was similar between the groups. Conclusions The newborn gender has a significant impact on the placental histopathology pattern, which can contribute to the development of adverse perinatal outcomes.