Maternal characteristics of preterm singleton birth following assisted reproduction: a population-based study

Objective To identify pregestational maternal characteristics that are associated with an increased risk for preterm births (PTB) of assisted reproductive technology (ART) singleton pregnancies.Patients and methods We evaluated the Slovenian National Perinatal Information System (NPIS). We included all ART singletons born during the period 2006–2015. We compared births before and after 36 completed weeks’ gestation for maternal age, parity, prepregnancy BMI, height, previous PTB, preexisting hypertension and diabetes, and history of uterine gynecological operations.Results Chronic hypertension (OR 2.5, 95% CI 1.3–4.8), previous preterm birth (OR 2.4, 95% CI 1.5–3.7), pregravid obesity (OR 1.6, 95% CI 1.2–2.1) and an existing indication for cerclage (OR 6.2, 95% CI 3.7–10.5) were associated with an increased risk of PTB.Conclusions Chronic hypertension, previous PTB, pregravid obesity and an existing indication for cerclage are associated with increased risk of PTB among ART pregnancies.