Risk Factors for Prolonged Intertwin Delivery Interval and Associated Maternal and Second Twin Morbidity

This work aimed to identify possible risk factors and the morbidity associated with prolonged intertwin delivery interval (IDI).

A retrospective cohort study at a single tertiary care center. Women with twin gestations who reached the second stage of labor between January 2010 and December 2019 were included in the study. Demographic and clinical characteristics were compared between short IDI (≤15 minutes) and prolonged IDI (>15 minutes). The primary outcome was the rate of 5-minute Apgar score ≤ 7.

A total of 461 women were included; 312 of whom were in the short IDI group and 149 were in the prolonged IDI group. Rates of 5-minute Apgar score ≤ 7 and neonatal acidemia were significantly higher in the prolonged IDI group (3.5 vs. 9.7%, p = 0.008; 4.3 vs. 15.7%, p = 0.01, respectively). Vaginal delivery was less likely to occur in the prolonged IDI group (75.8 vs. 93.3%). Placental abruption and hemoglobin drop ≥ 3 g/dL were more prevalent in the prolonged IDI group (4 vs. 1%, p = 0.03; 39.1 vs. 24.7%, p = 0.01, respectively). In the multivariate analysis, age ≥ 30 years (adjusted odds ratio [aOR]: 1.76, p = 0.01), nulliparity (aOR: 1.66, p = 0.03), and birth weight ratio ≥ 1.2 (aOR: 1.92, p < 0.05) were associated with prolonged IDI.

Prolonged IDI is associated with an increased risk for neonatal acidemia and low 5-minute Apgar score, and with an increased rate of cesarean delivery, placental abruption, and hemoglobin drop ≥ 3 g/dL. Advanced maternal age, nulliparity, and twin birth weight ratio ≥ 1.2 are associated with prolonged IDI.

· Prolonged was found to be associated with higher neonatal acidemia and lower 5-minute Apgar score.. · Prolonged IDI is also associated with increased rate of cesarean delivery, placental abruption, and blood loss.. · Advanced maternal age, birth weight discordancy, and nulliparity were associated with prolonged IDI..