Prenatal characteristics and factors contributing to congenital syphilis: A descriptive analysis of cases reported to the Canadian Paediatric Surveillance Program June 2021 through May 2023

Objectives The incidence of congenital (CS) in Canada increased from 2.1 to 14.5 reported confirmed cases/100,000 live births from 2017 to 2023 (from 8 to 53 cases). We aimed to document prenatal characteristics and contributing factors to CS among mothers or birthing parents (M/BP) of infants with CS in Canada. Methods Participants of the Canadian Paediatric Surveillance Program, which includes both paediatricians and paediatric subspecialists, were invited to report on CS cases meeting the study case definition between June 2021 and May 2023. A detailed questionnaire was completed by the reporting clinician. We used descriptive statistics in the assessment of prenatal risk factors among cases, including data on healthcare access, diagnosis, and treatment as well as on socio-demographic, socio-economic and socio-behavioural determinants. Results During the 24-month study period, 245 live-born cases of CS were reported, including 81 (33.1%) confirmed and 164 (66.9%) probable cases from seven provinces and territories. Substance use in pregnancy was reported in 65% of cases. Only half of M/BP had at least 1 prenatal care visit during their pregnancy, while only one-quarter had ≥ 1 prenatal care visit in each trimester. In a quarter of cases, no syphilis screening was performed during pregnancy. Prenatal syphilis treatment was not initiated among 20% who screened positive. Conclusion In this country-wide assessment, we identified substantial failures in the delivery of adequate prenatal care to M/BP of live-born infants diagnosed with CS. Public health action, such as community outreach to ensure prenatal care for all pregnant people, with specific attention to the prenatal healthcare needs and engagement in the care of those who use substances, is pressing.