Abstract
OBJECTIVE: To compare obstetric and perinatal outcomes between assisted reproductive technology (ART)-conceived and spontaneously conceived twin pregnancies using a nationwide Korean cohort. METHODS: This retrospective cohort study used Korean National Health Insurance Service data from October 2017 to December 2021. Twin pregnancies were identified via International Classification of Diseases, 10th revision codes and classified by conception type based on embryo transfer procedure codes. Outcomes included miscarriage, preeclampsia, placenta previa, gestational diabetes mellitus (GDM), emergency cesarean section (CS), intrauterine growth restriction (IUGR), and macrosomia. Multivariable logistic regression was used to calculate adjusted odds ratios (aORs), controlling for maternal age and comorbidities. Subgroup analyses stratified by maternal age were also performed. RESULTS: Among 36,013 twin pregnancies, those conceived via ART showed higher risks of placenta previa (aOR, 1.81; 95% confidence interval [CI], 1.57-2.08), preeclampsia (aOR, 1.31; 95% CI, 1.17-1.47), GDM (aOR, 1.32; 95% CI, 1.22-1.43), emergency CS (aOR, 1.21; 95% CI, 1.08-1.34), and IUGR (aOR, 1.18; 95% CI, 1.07-1.31). In women ≥35 years, risks were more pronounced for preeclampsia (aOR, 1.38; 95% CI, 1.19-1.61) and emergency CS (aOR, 1.22; 95% CI, 1.06-1.42). CONCLUSION: Twin pregnancies conceived via ART are associated with significantly increased risks of obstetric and perinatal complications compared with spontaneous conceptions. Given the growing utilization of ART, these findings underscore the importance of individualized prenatal care and vigilant perinatal monitoring in ART-conceived twin pregnancies, particularly among women of advanced maternal age.