[Factors influencing very preterm birth at less than 32 weeks of gestation: a multicenter retrospective study]

To explore the influencing factors for very preterm birth at a gestational age of <32 weeks in the Xinjiang Uygur Autonomous Region.

Clinical data of women with preterm deliveries and their newborns admitted to five hospitals in Xinjiang from January 2023 to December 2024 were retrospectively collected. The subjects were divided by gestational age into very preterm (<32 weeks of gestation) and moderate/late preterm (32-36⁺⁶ weeks of gestation) groups. Risk factors associated with very preterm birth were analyzed.

A total of 4 105 pregnant women with preterm deliveries were included, with 793 cases (19.32%) in the very preterm group and 3 312 cases (80.68%) in the moderate/late preterm group. The factors significantly associated with very preterm birth were as following: hypertensive disorders of pregnancy (OR=1.785, 95%CI: 1.492-2.135, P<0.05), excessive gestational weight gain (GWG, OR=2.002, 95%CI: 1.672-2.397, P<0.05), insufficient GWG (OR=1.746, 95%CI: 1.326-2.300, P<0.05), chorioamnionitis (OR=2.163, 95%CI: 1.694-2.763, P<0.05), premature rupture of membranes ≥18 hours (OR=2.158, 95%CI: 1.599-2.912, P<0.05), placental abruption (OR=2.228, 95%CI: 1.646-3.014, P<0.05), and ≤7 prenatal visits (OR=3.419, 95%CI: 2.882-4.055, P<0.05).

In the Xinjiang Uygur Autonomous Region, hypertensive disorders of pregnancy, excessive or insufficient GWG, chorioamnionitis, premature rupture of membranes ≥18 hours, placental abruption, and ≤7 prenatal visits are risk factors for very preterm birth. Strengthening high-risk pregnancy management is necessary for reducing the incidence of very preterm birth.