Sexually transmitted infections and bacterial vaginosis among adolescent girls and young women in the early postpartum period: a cross-sectional study

Universal antiretroviral treatment (ART) for pregnant women has reduced mother-to-child transmission risk significantly. However, not all women on ART are virally suppressed during pregnancy and lactation. In addition to poor adherence to ART, co-infections particularly other sexually transmitted infections (STIs) are known to increase the risk of HIV acquisition and HIV transmission. While the prevalence of STIs during pregnancy has been well studied, the prevalence of STIs in the postpartum period and its association with HIV viral suppression are underreported. In this cross-sectional study, we determined the prevalence of STIs among adolescent girls and young women (AGYW) living with HIV (WLHIV) and without HIV (WNLHIV) at their 6–14 week postnatal clinic visit in a high HIV prevalence district in South Africa. All women were examined for STI-related symptoms and had vaginal swabs collected and stored for later STI testing. Vaginal swabs were tested for Trichomonas vaginalis (T.vaginalis), Chlamydia trachomatis (C. trachomatis), Neisseria gonorrhoeae (N. gonorrhoea) and herpes simplex virus-2 (HSV-2) using PCR. All women were tested for bacterial vaginosis (BV) using the Nugent scoring criteria. WLHIV had a blood sample collected for HIV viral load, Hepatitis B and syphilis. Included in this analysis were 82 WLHIV and 102 WNLHIV. Between 6 and 14 weeks postpartum, 40 (21.7%) AGYW tested positive for any STI and among these 15 (37.5%) were symptomatic and received empirical treatment. C. trachomatis was most commonly detected (10.9%), followed by HSV-2 (7.7%), T. vaginalis (3.8%) and N. gonorrhoea (1.6%). WLHIV were more likely to test positive for an STI (OR 2.0; 0.96–3.96) and BV (OR 4.2; 95%CI 2.1–8.1) compared to WNLHIV. Among WLHIV on ART, 70.5% had an undetectable plasma viral load (PVL) and 20.5% had a PVL > 1000 copies/ml. Testing positive for any STI or BV at the postpartum visit was not associated with PVL > 1000 copies/ml (OR 1.33; 95%CI 0.38–4.64). We report a high prevalence of largely asymptomatic STIs and BV in the early postpartum period and STIs in WLHIV were not associated with unsuppressed PVL.The high STI positivity rate among WNLHIV has implications for HIV risk during the postpartum period, and subsequently breastfeeding transmission.