Use of combined contraceptive vaginal rings was associated with an increased risk for several types of sexually transmitted infections (STIs), based on data from a pair of studies presented at the annual clinical and scientific meeting of the American College of Obstetricians and Gynecologists (ACOG).
Previous research has shown that the use of a combined contraceptive vaginal ring (CCVR) may promote changes in immunity in the female genital tract by upregulating immune-related genes in the endocervix and immune mediators within the cervicovaginal fluid, wrote Amy Arceneaux, BS, a medical student at the University of Texas Medical Branch John Sealy School of Medicine, Galveston, and colleagues.
The infection rates in the female genital tract can vary according to hormones in the local environment and continued safety analysis is needed as the use of CCVR continues to rise, the researchers noted.
In a retrospective chart review, the researchers assessed de-identified data from TriNetX, a patient database, including 30,796 women who received etonogestrel and ethinyl estradiol CCVRs without segesterone and an equal number who were using oral contraceptive pills (OCP) without vaginal hormones. Patients were matched for age, race, and ethnicity.
Overall use of CCVRs was significantly associated with an increased risk for Herpes simplex virus 2 (HSV-2; relative risk [RR], 1.790), acute vaginitis (RR, 1.722), subacute/chronic vaginitis (RR, 1.904), subacute/chronic vulvitis (RR, 1.969), acute vulvitis (RR, 1.894), candidiasis (RR, 1.464), trichomoniasis (RR, 2.162), and pelvic inflammatory disease (RR, 2.984; P < .0005 for all).
By contrast, use of CCVRs was significantly associated with a decreased risk for chlamydia (RR, 0.760; P = .047). No differences in risk appeared for gonorrhea, syphilis, HIV, or anogenital warts between the CCVR and OCP groups.
Another study presented at the meeting, led by Kathleen Karam, BS, also a medical student at the University of Texas Medical Branch John Sealy School of Medicine, Galveston, Texas, focused on outcomes on vaginal health and infection risk in women who used CCVRs compared with women who did not use hormones.
The study by Ms. Karam and colleagues included de-identified TriNetX data for two cohorts of 274,743 women.
Overall, the researchers found a significantly increased risk for gonorrhea, HSV-2, vaginitis, vulvitis, pelvic inflammatory disease, anogenital warts, and candidiasis in women using CCVR compared with those using no hormonal contraception, while the risk for chlamydia, syphilis, and HIV was decreased in women using CCVR compared with those using no hormonal contraception.
“I was pleasantly surprised by the finding that the group of women using the hormonal contraception vaginal ring had decreased risk for HIV and syphilis infections,” said Kathleen L. Vincent, MD, of the University of Texas Medical Branch John Sealy School of Medicine, Galveston, Texas, and senior author on both studies, in an interview. She hypothesized that the estrogen released from the ring might have contributed to the decreased risk for those infections.
The findings of both studies were limited primarily by the retrospective design, but the results suggest a need for further study of the effect of local hormone delivery on the vaginal mucosa, the researchers wrote.
Although the study population was large, the lack of randomization can allow for differences in the behaviors or risk-taking of the groups, Dr. Vincent said in an interview.
“The fact that there were STIs that were increased and some that were decreased with use of the vaginal ring tells us that there were women with similar behaviors in both groups, or we might have seen STIs only in one group,” she said. “Additional research could be done to look at varying time courses of outcomes after initiation of the vaginal ring or to go more in-depth with matching the groups at baseline based on a history of risky behaviors,” she noted.