COVID-19 Vaccination and the Risk of Preterm Labor: A Cross-Sectional Study in Karachi, Pakistan
Vaccination and Preterm Labor Risk
Keywords:
COVID-19, vaccination, pregnancy, preterm labor, maternal health, neonatal outcomes, Pakistan, public healthAbstract
Abstract
Background
Preterm birth accounts for a majority of neonatal morbidity and mortality globally. The COVID-19 pandemic added extra maternal stressors that have the potential to impact pregnancy outcome. This investigation explores whether maternal COVID-19 vaccination is related to decreased preterm labor and better neonatal health outcomes.
Methods
A comparative cross-sectional study was conducted at a public hospital in Karachi, Pakistan, including 200 pregnant women (100 vaccinated, 100 unvaccinated). Preterm labor was defined as delivery before 37 weeks of gestation. Data on vaccination status, maternal demographics, and pregnancy outcomes were analyzed using chi-square tests, independent t-tests, multivariate logistic regression, Cox proportional hazards models, and propensity score matching.
Results
Preterm labor was significantly reduced in the vaccinated group (7%) than in the unvaccinated group (15%) (p = 0.04). Adjusted multivariate analysis revealed that vaccinated mothers had 54% reduced odds of preterm labor (aOR = 0.46, 95% CI: 0.21-0.98, p = 0.04). Propensity score matching sensitivity analysis validated this relationship (aOR = 0.44, 95% CI: 0.19-0.92, p = 0.04). Cox proportional hazards modeling hazard ratio was 0.52 (95% CI: 0.27-0.99, p = 0.04), which represented 48% lower preterm birth hazard among vaccinated mothers. Neonatal ICU admissions were also lower in vaccinated mothers (5% vs. 12%, p = 0.03), and birth weight was higher (3100 ± 450 g vs. 2900 ± 520 g, p = 0.02). No differences were seen by vaccine type or trimester of vaccination.
Conclusions
COVID-19 vaccination among pregnant women has a substantially reduced risk of preterm labor, reduced neonatal ICU admissions, and better birth weight outcomes. These findings strongly endorse integrating maternal COVID-19 vaccination into standard antenatal care in low-resource settings to improve maternal and neonatal health.
Keywords
COVID-19, vaccination, pregnancy, preterm labor, maternal health, neonatal outcomes, Pakistan, public health
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