LA JOLLA, CALIF. — Spermicides containing nonoxynol-9 are a safe alternative for women who are at low risk of acquiring sexually transmitted infections, according to a study from the University of Pittsburgh.
Use of an N-9 spermicide was compared with condom use in two cohorts of women in mutually monogamous heterosexual partnerships requiring long-term contraception, who had no sexually transmitted infections (STIs) or suspicion of STIs at the time of enrollment, said Dr. Bryna Harwood, now with the University of Illinois at Chicago.
“Overall, when we looked at users of any type of spermicide compared to condom users, the risk of having a lesion at follow-up colposcopy was similar in both groups. Interestingly, the condom group had a statistically significant increase in lesions characterized by epithelial disruption,” Dr. Harwood said at the annual meeting of the Association of Reproductive Health Professionals. Epithelial disruption is more commonly associated with N-9 spermicide use in high-risk settings, and lesions with epithelial disruption may increase the risk of acquiring HIV.
The finding comes 9 months after the Food and Drug Administration issued a nonbinding draft guidance warning that N-9 could irritate the vagina and rectum and increase STI risk. The FDA also recommended that the package inserts for latex condoms specify that they cannot entirely protect against STIs such as human papillomavirus and genital herpes.
The primary goal of this multicenter, randomized clinical trial was to compare the efficacy of different N-9 spermicide formulations. Participants were randomized to one of five formulations—gel, film, or suppository—for coital use. The colposcopic appearance of the genital epithelium was assessed in a substudy of 136 low-risk women assigned to one of the spermicide groups. At one center, 30 women whose partners used condoms were enrolled as a control group. All participants were followed over 6 months during spermicide or condom use. The mean numbers of coital acts per week (about two) were similar between groups.
Colposcopic lesions were described using CONRAD Program/World Health Organization standardized procedures, said Dr. Harwood, of the department of obstetrics and gynecology at the University of Illinois.
New lesions were identified in 48% of visits for spermicide users and in 51% of visits for condom users. However, lesions with epithelial disruption were present in only 11% of spermicide users versus 37% of condom users, Dr. Harwood explained.
In a discussion of the study, Dr. Christine Mauck said these findings are consistent with earlier observations that the differences in lesions between placebo and N-9 are seen only in frequent users. “I think the bottom line is that N-9 may be safe in women who don't use it frequently and are at low risk for HIV and STIs, and that's probably a lot of women we see in our practices, said Dr. Mauck, who is senior medical adviser for CONRAD in Arlington, Va.