Copper intrauterine devices up risk of T. vaginalis infection

The risk of contracting Trichomonas vaginalis (TV) infection seems to be higher in women using copper intrauterine devices (Cu-IUD) as a contraceptive, according to a study presented at the recently concluded 2021 International AIDS Society Conference on HIV Science (IAS 2021).

“TV and Mycoplasma genitalis (MG) are associated with numerous adverse reproductive health sequelae among women, but data on their prevalence among women using contraceptive methods are limited,” the researchers said. The present study aimed to determine the effect of different contraceptive methods—including Cu-IUD, levonorgestrel (LNG) implant, and injectable depot medroxyprogesterone acetate (DMPA-IM)—on the frequency of these infections.

Drawing from the Evidence for Contraceptive Options in HIV Outcomes (ECHO) trial, the researchers conducted a three-site (Cape Town, Johannesburg, and Kisumu) nested study, randomly assigning 458 women to receive DMPA-IM, Cu-IUD, or LNG implants. Study outcomes were TV and MG rates compared across intervention arms. Incident symptomatic sexually transmitted infections (STI) were treated during follow-up.

Overall, the prevalence rates of TV and MG infections were 9.2 percent and 8.4 percent, respectively. These were highest in the Cape Town site (11.8 percent and 9.1 percent, respectively) and lowest in Johannesburg (3.3 percent and 6.7 percent, respectively). [IAS 2021, abstract PEB094]

Stratifying analysis according to the contraceptive method showed that TV was significantly more prevalent among women using Cu-IUDs relative to DMPA-IMs or LNG implants (15.3 percent vs 5.6 percent and 6.5 percent). No such effect was reported for MG.

Logistic regression analysis, adjusted for age, study site, and prostate-specific antigen, confirmed these findings. The likelihood of contracting TV infection was significantly higher among women using Cu-IUD as compared with DMPA-IM (odds ratio [OR], 3.57, 95 percent confidence interval [CI], 1.47–8.69) or LNG implant (OR, 2.86, 95 percent CI, 1.30–6.28).

In contrast, DMPA-IM and LNG implant conferred comparable risks of TV (OR, 0.80, 95 percent CI, 0.29–2.19). MG likewise remained unaffected by the type of contraceptive used, with ORs ranging from 0.81 to 0.92, none of which achieved statistical significance.

 “TV and MG are highly prevalent among reproductive aged women in these settings. The significantly higher TV risk among Cu-IUD users when controlling for PSA detection suggests a biologic, rather than behavioural, mechanism and corroborates earlier findings,” the researchers said.

“TV is associated with numerous adverse reproductive health sequelae and is a risk factor for other STIs including HIV,” they added. “Consideration should be given to STI counseling and testing among Cu-IUD users. Additional research is needed to understand the biological mechanisms of potential increased TV risk among Cu-IUD users.”