METHODS: Data were obtained from the China\'s Information System of Prevention of Mother-to-Child Transmission in Jiangxi Province. All syphilis infected pregnant women who delivered ≥28 gestational weeks and were registered in this system between 1 January 2013 and 31 December 2019 were enrolled. Pregnancy outcomes were evaluated by group-specific analyses according to their treatment status, adequacy and initiation time.
RESULTS: 4210 syphilis infected pregnant women were included in the analyses. Infants born to untreated mothers (n = 1364) were at significantly higher risk for stillbirth (adjusted odds ratio (aOR) = 1.74, 95% CI, 1.01-3.00, P = 0.045), preterm birth (aOR = 1.27, 95% CI, 1.02-1.59, P = 0.034) and low birth weight (LBW) (aOR = 1.44; 95% CI, 1.11-1.86, P = 0.006) than those born to treated mothers (n = 2846) after adjustment for confounding factors. A significantly higher risk of stillbirth (aOR = 3.68; 95% CI, 1.62-8.34, P = 0.002), preterm birth (aOR = 2.26; 95% CI, 1.71-3.00, P < 0.001), LBW (aOR = 2.23; 95% CI, 1.59-3.14, P < 0.001) and congenital syphilis (CS) (aOR = 3.63; 95% CI, 1.80-7.31, P < 0.001) was found in infants exposed to mothers treated inadequately (n = 1299) than those treated adequately (n = 1547). No pregnant women who initiated the treatment in the first trimester (n = 682) delivered a neonatal CS case. Compared with mothers who initiated treatment in the first trimester (n = 682), those initiated in the third trimester (n = 1234) suffered an increased risk of stillbirth (aOR = 4.48; 95% CI, 1.31-15.30, P = 0.017), preterm birth (aOR = 2.34; 95% CI, 1.61-3.40, P < 0.001) and LBW (aOR = 3.25; 95% CI, 1.97-5.37, P < 0.001).
CONCLUSIONS: Maternal treatment, especially early and adequate treatment, plays a crucial role in mitigating adverse pregnancy outcomes among syphilis infected women.