# P-504. Eight Years of Maternal Syphilis in Northern Mexico: Clinical and Demographic Profiles and Congenital Outcomes

## TL;DR

This study analyzes maternal and congenital syphilis cases in Northern Mexico from 2015 to 2022, highlighting poor prenatal care and treatment adherence as key factors in high rates of adverse neonatal outcomes.

## Contribution

The study provides detailed clinical and demographic insights into maternal syphilis and congenital outcomes in Northern Mexico over an eight-year period.

## Key findings

- Only 57% of pregnant women with syphilis attended adequate prenatal care.
- 26% received outpatient antibiotic treatment after a positive syphilis test.
- 13.5% of newborns had confirmed congenital syphilis, with 3.5% resulting in stillbirths.

## Abstract

Maternal and congenital syphilis remain significant global health issues, with >500,000 cases annually worldwide and serious outcomes including stillbirth, prematurity, low birth weight, and neurological damage. In Mexico, the steady rise in maternal syphilis reflects persistent challenges in early detection and follow-up, particularly in primary care. While national surveillance systems capture cases of acquired and congenital syphilis, they often lack clinical detail on neonatal outcomes, limiting a comprehensive evaluation.CS= Congenital Syphilis

We conducted a retrospective analysis of clinical data from pregnant women with a positive VDRL test and their newborns diagnosed at the Maternal and Pediatric Reference Hospital (HRMI) in NL, Mexico, between 2015 - 2022. Variables included maternal age, prenatal care, syphilis treatment, HIV coinfection, and neonatal outcomes classified according to CDC criteria. Descriptive statistics (frequencies, percentages, means, and ranges) were used to characterize maternal profiles and the congenital syphilis outcomes.

Clinical data from 1615 VDRL-positive pregnant women at the time of delivery along with their newborns (1619) were included. Mean maternal age was 22 ± 5.8 years. Alarmingly, only 923 (57%) attended adequate prenatal care, and only 426 (26%) received outpatient antibiotic treatment after the first positive VDRL test. Maternal HIV testing at the time of delivery revealed 22 women with a positive test (1.4%), all of which were novel diagnoses. Neonatal outcomes based on the CDC classification were as follows: 219 confirmed cases (13.5%), 1033 probable cases (63.8%), 301 possible cases (18.6%), and 66 syphilis exposure cases (4.1%). Of the probable cases, 721 newborns were considered at high-risk of developing congenital syphilis (44.5%) and were treated as such. A total of 57 stillbirths were documented (3.5%).

Despite being a preventable condition, congenital syphilis (CS) remains a major burden in Northern Mexico. Low prenatal care coverage and missed treatment opportunities continue to drive high rates of adverse neonatal outcomes. Strengthening early detection and timely treatment during pregnancy is critical to prevent avoidable morbidity and mortality.

All Authors: No reported disclosures