Hormonal contraceptives, genital tract infections influence cervical immunology
Interactions between hormonal contraceptives and various genital tract infections may alter cervical immunity and increase the risk for HIV seroconversion among women, according to recently published data.
“Before this study, there were all these controversial reports, some showing that [depot medroxyprogesterone acetate (DMPA)] increases the risk of HIV infection and others showing it doesn’t, and there was no biologic explanation for the differences between studies,” researcher Raina N. Fichorova, PhD, MD, of Harvard Medical School, said in a press release. “This new study offers an explanation for the inconsistent studies, and it lies in the microbial communities of the reproductive tract.”
Raina N. Fichorova
Fichorova and colleagues analyzed the impact of infection and hormonal contraceptives (HCs) within a cohort of 832 women enrolled in Uganda and Zimbabwe. Participants were divided into groups based on the use of injectable DMPA, combined oral contraceptives (COC) or non-HC alternatives, with women recently infected with HIV (n = 199) compared with those who remained uninfected (n = 633) during a 6-month follow-up. Cervicovaginal infections (CVI) were diagnosed using PCR, antibody enzyme-linked immunosorbent assay (ELISA), wet mount and Nugent scoring. Samples collected via cervical Dacron swabs also were processed and simultaneously measured for the presence of eight cervical immunity biomarkers.
The researchers found that women using COC and DMPA had lower rates of lab-confirmed CVIs compared with those using no HCs (P =.046). In addition, Trichomonas vaginalis infection was associated with abnormal immunity among the non-HC group.
Among women with no genital infection and a normal Nugent score, COC users showed higher levels of the proteins IL-1 beta, IL-6, IL-8 and IL-1RA. This increase was reduced with the detection of gonorrhea, chlamydia, trichomoniasis, candidiasis and an abnormal Nugent score, while RANTES was increased with herpes, chlamydia and an abnormal Nugent score. Meanwhile, DMPA users without infection demonstrated higher levels of proteins associated with HIV seroconversion. Also, reductions in immunity levels were seen between IL-1RA and gonorrhea, chlamydia and herpes; secretory leukocyte protease inhibitor and gonorrhea; and IL-1 beta, MIP-3 alpha and IL-1RA/IL-1 beta ratio with trichomoniasis.
These altered levels of immunity proteins among women with various CVI using HC provide evidence of interactions worthy of increased consideration, the researchers wrote.
“Cervicovaginal pathogens and altered vaginal microbiota contribute to the differences in the effects of HC on the cervical mucosal immune environment in HIV-negative women,” Fichorova and colleagues wrote. “A deeper understanding of the pathogen-HC interactions may provide further insights for development of targeted interventions based on HC use and CVI status to improve reproductive health in women.” – by Dave Muoio
Disclosure: The researchers report no relevant financial disclosures.