Determinants of preterm birth among women delivered in Orotta National Maternity Referral Hospital, Eritrea: a case-control study

Abstract Background Preterm birth remains a leading cause of neonatal morbidity and mortality globally, with a disproportionate burden in sub-Saharan Africa. Despite sustained investments in maternal health services in Eritrea, context-specific evidence on determinants of preterm birth is limited. This study aimed to identify determinants of preterm birth among women delivering at Orotta National Maternity Referral Hospital, Eritrea. Methods An unmatched case-control study was conducted from June 2023 to April 2024. Data were collected using structured interviews and medical record review. Descriptive statistics and logistic regression were employed using IBM SPSS (version-27.0). Results A total of 336 women participated in the study, comprising 112 preterm cases and 224 term controls. In the overall maternal population, BMI < 18.5 kg/m² (AOR = 5.16, 95% CI: 2.15, 12.39), exposure to pregnancy-unrelated medications (A/B categories: AOR = 3.81, 95% CI: 1.02, 14.23; C/D/X categories: AOR = 8.37, 95% CI: 2.34, 29.88), fewer than three antenatal care (ANC) visits (AOR = 7.27, 95% CI: 3.00, 17.65), 4 to 7 ANC visits (AOR = 2.31, 95% CI: 1.16, 4.60), and bleeding during the current pregnancy (AOR = 5.02, 95% CI: 2.25, 11.20) were significantly associated with preterm birth. Among multigravida women, BMI < 18.5 kg/m² (AOR = 5.84; 95% CI: 1.86, 18.36), exposure to pregnancy-unrelated medications (C/D/X categories: AOR = 5.93; 95% CI: 1.05, 33.59), fewer than three ANC visits (AOR = 6.65; 95% CI: 1.91, 23.18), bleeding during the current pregnancy (AOR = 5.30; 95% CI: 1.82, 15.37), and history of abortion (AOR = 2.49, 95% CI: 1.12,5.52) were significantly associated with preterm birth. Conclusion Preterm birth is significantly associated with maternal undernutrition, inadequate antenatal care utilization, pregnancy complications, and adverse reproductive history. Strengthening nutritional support, early risk identification, and comprehensive antenatal services may substantially reduce preventable preterm births.