The burden imposed by twin pregnancies οn a high-risk pregnancy unit: A retrospective cohort study in Greece

Introduction: Twin pregnancies are associated with several pregnancy complications often necessitating admission for close surveillance. The present study aimed to investigate the burden imposed by twin pregnancies on a high-risk pregnancy unit (HRPU) of a tertiary hospital. Materials and Methods: This was a retrospective cohort study conducted between January 2017 and December 2022 in the Third Department of Obstetrics and Gynecology, School of Medicine, Aristotle University of Thessaloniki, Greece. All women with twin pregnancies admitted in the HRPU were eligible to participate. The duration of hospitalization and the outcome of the pregnancy were the main outcomes of the study. Secondary outcomes were the associations between the duration and the pregnancy outcome and several maternal and obstetrical parameters. Results: From a total of 1,351 women hospitalized in the HRPU during the study period, 154 (11.4%) women were carrying twins. The mean duration of hospitalization was 6.1 days (± 6), the main indication for admission was threatened preterm labor (TPTL) (37%) and most cases ended up in delivery (64.9%). Advancing maternal age (OR: 1.066; 95% CI: 1.010-1.126; p=0.02), early gestational age on admission (OR: 0.807; 95% CI: 0.718-0.907; p<0.001) and fetal growth restriction (FGR) (OR: 2.728; 95% CI: 1.035-7.189; p=0.042) were identified as independent risk factors for longer stay at the HRPU. With regards to pregnancy outcome, advancing gestational age on admission (OR: 1.158; 95% CI: 1.044-1.285; p=0.006) and preterm prelabor rupture of membranes (PPROM) (OR: 6.239; 95% CI: 1.712-22.741; p=0.006) were identified as independent risk factors for delivery, instead of discharge. Conclusions: About one out of nine hospitalized high-risk pregnancies were twins, thus, imposing a high burden for the HRPU, while one third of them had symptoms of TPTL. Close antenatal care is required for twin pregnancies to early detect possible complications and thus, improve perinatal outcomes.