Deconstructing Perinatal Health Disparities An Analytical Cross-Sectional Study of Parental Social Determinants and Clinical Preterm Birth Subtypes in Karimnagar, India

Background: Preterm birth, defined as delivery before 37 completed weeks of gestation, is a leading cause of neonatal and under five mortality. Spontaneous and provider initiated preterm birth arise through different clinical pathways yet are often analyzed together. We examined associations of maternal and paternal education, antenatal care utilization, pre-gestational diabetes and chronic hypertension with each subtype, using full term birth as the reference. Methods: This analytical cross sectional study was conducted at a tertiary care teaching hospital in Karimnagar, Telangana, India, from May to July 2024. Of 172 eligible primiparous women with singleton live births, 150 with complete paternal data were analyzed, comprising 50 full term births, 75 spontaneous preterm births and 25 provider initiated preterm births. Gestational age was established by first trimester crown rump length reconciled with the last menstrual period. Binary logistic regression, with a secondary multinomial model, produced crude and adjusted odds ratios with 95 percent confidence intervals, and E-values assessed robustness to unmeasured confounding. Results: Mean maternal age was 24.6 years. Maternal college education was associated with lower odds of spontaneous preterm birth, with an adjusted odds ratio of 0.38 and a 95 percent confidence interval of 0.16 to 0.92, but not of provider initiated preterm birth. Paternal college education was associated with lower odds of both subtypes. Six or fewer antenatal visits, pre-gestational diabetes and chronic hypertension were associated with higher odds of both subtypes, with adjusted odds ratios from 2.41 to 4.82. Severe pre-eclampsia or eclampsia was the leading indication for provider initiated delivery, accounting for 40 percent of cases. Conclusions: In this selected tertiary care cohort, education, antenatal care and cardiometabolic factors were differentially associated with preterm birth subtypes. Because of the single center design, the small provider initiated group and gestational age bias in visit counts, the findings are exploratory and associational. Larger prospective multicenter studies are warranted.