High Prevalence of Sexually Transmitted Infections in Pregnant Women Living in Southern Brazil

Abstract

Background: Porto Alegre, Brazil, has the highest rates of congenital syphilis and HIV in the country. Other treatable sexually transmitted infections (STIs) are associated with poor pregnancy and neonatal outcomes, but are only diagnosed by syndromic algorithms.

Methods: Between September 2018 and November 2019, we offered all pregnant women clinic-based STI testing for HIV antibody and treponemal antibody (via lateral flow assay rapid tests provided by the Brazilian Government) and for Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis (via polymerase chain reaction-based testing provided by Gene Xpert, Sunnyvale, CA) in 10 public prenatal health clinics in Porto Alegre. Participating women answered a brief survey via audio computer-assisted survey instrument regarding demographics, partnerships, and sexual behaviors. All infected individuals received appropriate treatment and referrals.

Results: Of 400 pregnant women recruited, 94 (24%) were diagnosed with an STI, including 2% with HIV, 11% with syphilis, 9% with chlamydia, 1% with gonorrhea, 5% with trichomoniasis, and 3% with more than 1 STI. In our multivariate analysis, younger age (adjusted odds ratio [AOR], 1.1; 95% confidence interval [CI], 1-1.2), being non-White (AOR, 1.8; 95% CI, 1.1-3.1), having less education (AOR, 2; 95% CI, 1.2-3.4), and having a relationship <1 year (AOR, 2; 95% CI, 1.1-3.6) were all independent predictors of women having an STI. Endorsing symptoms of an STI (e.g., vaginal ulcers/lesions and vaginal discharge) was not predictive of having a laboratory-diagnosed STI (OR, 1.1; 95% CI, 0.7-1.7).

Conclusions: Etiologic-based screening for STIs was uniformly accepted by women attending both hospital-based and primary health clinics in the south of Brazil and can result in appropriate treatment of pregnant women.

Figure 1

Flowchart of enrollment and distribution of STIs in pregnant women in the study. Among 400 women screened, 24% had a positive result for at least 1 STI, and 3% had positive results for more than 1.

Figure 2

Proposed conceptual framework of factors increasing vulnerability to STIs during pregnancy.