(P436) Syphilitic Stillbirths and Syphilitic Neonatal Deaths in Florida, USA, 2012-2021

Background

Untreated syphilis in pregnant women can lead to syphilitic stillbirth or syphilitic neonatal deaths (SS/SND). Reported congenital syphilis (CS) cases in Florida increased 362% from 39 in 2013 to 180 in 2021. We evaluated how this increase in CS changed the proportion of cases resulting in SS/SND and assessed risk factors for SS/SND.

Methods

Reported cases of CS from 2012-2021 were extracted from Florida’s sexually transmitted diseases surveillance system. These cases were categorized by SS/SND status within 1 year of delivery. Frequencies and proportions of CS cases resulting in SS/SND were assessed. CS cases were stratified by SS/SND outcomes and assessed for categorical odds ratios (univariate and logistic regression) based on maternal age, race/ethnicity, maximum non-treponemal titer (NTT) during pregnancy (proxy for infection intensity), syphilis stage, drug use, and prenatal care (proxy for duration of infection). CS cases resulting in SS/SND were examined for weeks gestational age (WGA) at delivery and screening practices during pregnancy.

Results
CS cases were reported in 911 infants; 10% were SS (75) or SND (15), 13 of whom died ≤7days from birth. SS/SND increased from 3 in 2012 to 23 in 2021. SS/SND ranged between 8% and 13% of CS cases for all years except 2014 (2%). Mothers with high (1:32 or 1:64) (aOR=4.0 95%CI 1.9-8.6) or very-high NTT (≥1:128) (aOR=6.0 95%CI 2.7-13.6) and lack of prenatal care (aOR=3.5 95%CI 2.0-5.9) were more likely to be an SS/SND. SS/SND occurred at 20–26 WGA (27; 30%); 27–33 WGA (47; 52%), and 34–40 WGA (16; 18%). Of the SS/SND, 64 (71%) had no screening >30 days prior to delivery; 17 (19%) tested negative prior to an SS/SND, and 9 (10%) tested positive at initial screening. The shortest times from negative test to SS/SND were 56 and 62 days (median=145).

Conclusions

Frequency of SS/SND in Florida increased but the proportion remained relatively stable. Maternal high-titer NTT and no prenatal care were risks for SS/SND. Engaging pregnant women in prenatal care along with screening early in pregnancy with timely treatment could prevent most SS/SND. Rescreening is valuable as SS/SND can occur 2 months after a negative prenatal test.