Association between maternal syphilis treatment and adverse pregnancy outcomes

Abstract

Objective To examine the association between maternal syphilis treatmentand the adverse pregnancy outcomes. Methods Syphilis-infected pregnant women retrieved from Information System of Prevention Mother-to-child Transmission of Human Immunodeficiency Virus (HIV), Syphilis, and Hepatitis B Management in Hu′nan Province between January 2012 and December 2017 were retrospectively studied. Information of demographic characteristics, pregnancy history, and syphilis infection/treatment history among these syphilis-infected pregnant women were collected and analyzed. According to the anti-syphilis treatment situation during pregnancy, syphilis-infected pregnant women were divided into three groups: non-treatment group, non-standardized treatment group and standardized treatment group. The incidences of adverse pregnancy outcomes among the three groups were calculated. Multivariate logistic regression was used to control confounding factors and analyze the association between maternal syphilis treatment and the adverse pregnancy outcomes. The adjusted odds ratios (aOR) and 95% confidence interval (CI) were calculated. Results Among 9 059 syphilis-infected pregnant women, 13.9% (1 262), 31.3% (2 834), and 54.8% (4 963) were untreated, non-standardized treated and standardized treated patients, respectively. The incidences of total adverse pregnancy outcomes in the non-treatment, non-standardized treatment and standardized treatment groups were 25.5%(322), 20.8%(589), and 16.2%(806), respectively. The incidences of stillbirth in the three groups were 2.3%(29), 1.3%(38), and 0.6%(28), respectively; those of preterm birth were 12.6%(159), 10.5%(297), and 6.0%(299), respectively; those of low birth weight were 6.4%(81), 6.2%(175), and 3.3%(162), respectively; those of small for gestational age were 10.9%(138), 8.4%(237), and 8.0%(399), respectively; those of neonatal death were 1.3%(17), 1.0%(28) and 0.3%(15), respectively; those of neonatal asphyxia were 1.9%(24), 0.9%(25), and 0.9%(46), respectively; those of neonatal pneumonia were 0.6%(8), 0.9%(26), and 0.6%(32), respectively; those of birth defects were 2.8%(35), 1.3%(37), and 1.1%(57), respectively; those of neonatal congenital syphilis were 2.5%(31), 2.4%(69), and 0.8%(42), respectively. Compared with standardized treatment group, maternal syphilis without treatment was associated with increased risks of total adverse pregnancy outcomes (aOR=1.73), stillbirth (aOR=4.82), preterm birth (aOR=2.52), low birth weight (aOR=1.88), neonatal death (aOR=3.29), neonatal asphyxia (aOR=2.42) and birth defects (aOR=3.26) all P<0.01; maternal syphilis with non-standardized treatment was associated with increased risks of total adverse pregnancy outcomes (aOR=1.34), stillbirth (aOR=2.54), preterm birth (aOR=1.98), low birth weight (aOR=1.84), neonatal death (aOR=2.49) and neonatal congenital syphilis (aOR=1.70, P<0.05 or 0.01). Conclusions Maternal syphilis without treatment or with non-standardized treatment would increase the risks of adverse pregnancy outcomes. It is necessary to further strengthen the early screening and early treatment for syphilis-infected pregnant women, and improve the rate of standardized treatment to reduce the occurrence of adverse pregnancy outcomes. Key words: Syphilis; Pregnant women; Treatment; Adverse pregnancy outcomes