Mycoplasma genitalium infection among HIV-infected pregnant African women and implications for mother-to-child transmission of HIV

Abstract

Objective:

Many sexually transmitted infections (STIs) increase risk of mother-to-child transmission (MTCT) of HIV, but the effect of Mycoplasma genitalium (MG) is not known. We hypothesized that MG infection would be common among HIV-infected pregnant women and could be associated with in utero and intrapartum MTCT.

Design:

Observational case-cohort study

Methods:

This study used specimens from a Kenyan perinatal MTCT cohort (1999-2005) involving HIV-infected women and their infants, who received short-course zidovudine for prevention of MTCT. Vaginal swabs collected at 32 weeks gestation were tested for MG using a transcription-mediated amplification assay. Infant perinatal HIV infection was determined at birth and 4 weeks of age by DNA PCR. Using a case-cohort design, a random sample was generated with 3:1 control: case ratio; prevalence and correlates of MG were assessed with Chi-squared and t-tests; predictors of infant outcomes were analyzed using logistic regression.

Results:

Among 220 HIV-infected pregnant women evaluated, 47 women (21.4%) had MG. Antenatal MG infection was associated with higher HIV RNA in plasma (5.0 vs. 4.6 log ₁₀ copies/ml in MG-positive vs. MG-negative women, p=0.02) at 32 weeks. Women with MG were less likely to report prior STIs and genital ulcers (both p=0.05). There was no association found between exposure to MG and perinatal MTCT (OR=0.72, 95% CI 0.35, 1.51, p=0.39).

Conclusions:

Vaginal MG infection was frequently detected among Kenyan HIV-infected pregnant women and was associated with higher plasma HIV levels, but was not associated with perinatal transmission of HIV.