Association Between Maternal Syphilis Infection and Stillbirth Among Women Delivering at Jinja and Hoima Regional Referral Hospitals: An Unmatched Case-Control Study.

BACKGROUND AND AIMS: Maternal syphilis infection remains a preventable contributor to stillbirth in low- and middle-income countries. Evidence on its distribution among stillbirth deliveries, its independent association with fetal death, and the role of infection severity remains limited in Ugandan referral hospitals. This study aimed to compare maternal syphilis infection between stillbirth and live-birth deliveries, estimate its adjusted association with stillbirth, and assess whether maternal rapid plasma reagin (RPR) titers showed a dose-response relationship with stillbirth. METHODS: A hospital-based unmatched case-control study was conducted among 406 women delivering at Jinja and Hoima Regional Referral Hospitals from January to April 2026. Maternal syphilis infection was determined using serologic testing. Group differences were assessed using chi-square tests, and multivariable logistic regression estimated adjusted odds ratios (AORs) and 95% confidence intervals (CIs). RESULTS: Maternal syphilis infection was more common among stillbirth deliveries than live births (11.9% vs. 3.7%; χ 2 (1) = 10.015, p = 0.002). After adjustment, maternal syphilis infection was associated with higher odds of stillbirth (AOR 3.91, 95% CI: 1.65-9.31; p = 0.002). Increasing RPR titer category was associated with increasing odds of stillbirth (ordinal trend OR 1.98, 95% CI: 1.26-3.12; p = 0.003). CONCLUSION: Maternal syphilis infection was independently associated with stillbirth, and higher RPR titer categories showed a graded association with stillbirth. These findings support strengthened antenatal syphilis screening, timely treatment, and risk-based follow-up in referral-hospital settings.