Delivery and feto-neonatal outcomes of diamniotic twin pregnancies in women with no chronic disease or gestational complications: impact of mode of conception

Introduction: Autologous and heterologous assisted reproductive technology (ART) conceptions have been on the rise for the last few decades and alongside with that have the rate of multiple pregnancies. Multiple gestations are associated with high odds of gestational complications and, in turn, adverse delivery and feto-neonatal outcomes. Whether ART-conception further increases such elevated risk is still debated. ART is more commonly accessed by older women with chronic diseases, which relate to heightened likelihood of complications. We decided to investigate the influence of autologous and heterologous ART conception compared to spontaneous conception on delivery and feto-neonatal outcomes of diamniotic twin pregnancies in a cohort of healthy women with no chronic conditions or gestational complications. Materials and methods: Retrospective cohort study among diamniotic twin pregnancies in mothers without pregestational or gestational disease. Delivery and feto-neonatal outcomes were compared among three groups according to mode of conception: (1) spontaneous conception (SC, referent group, n = 251 pregnancies), (2) autologous ART-conception (A-ART, n = 87), and (3) heterologous ART-conception (H-ART, n = 22). Results: At adjusted analyses, twin pregnancies conceived by A-ART showed a twofold heightened risk of delivery by urgent/emergent cesarean section, as well as four and sevenfold increase in odds of blood loss >1000 and >1500 mL, respectively. H-ART pregnancies were at fivefold higher risk of undergoing prelabor cesarean section compared to SC, whereas no differences were identified for odds of severe post-partum hemorrhage. Also, A-ART and H-ART gestations displayed fetal and neonatal outcomes similar to SC pregnancies when analysis was adjusted for relevant confounding factors. Conclusion: Our results suggest that both A-ART and H-ART conception associate with increased odds of operative delivery among diamniotic twin pregnancies in healthy mothers with no chronic diseases or gestational complications. Also, a higher risk of severe postpartum hemorrhage appears to relate to A-ART independent of mode of delivery and maternal age. Further studies with larger series of uncomplicated twin pregnancies are warranted to improve our understanding of the relationship of ART to adverse delivery outcomes.