A clinical trial involving 5,045 women in South Africa and Zimbabwe found no statistical difference in the rate of new HIV infections in the two study arms: those who received a diaphragm plus lubricant along with male condoms for their partners and those who only received male condoms.
"In the context of a comprehensive HIV prevention package provided to all participants, the trial found no additional protective benefit against HIV infection from adding the diaphragm plus lubricant in the intervention arm," said the trial's lead investigator, Nancy Padian, PhD, director of UCSF's Women's Global Health Imperative.
The study, to be published online in The Lancet, reported an overall HIV incidence rate of 4.0 percent: 4.1 percent in the intervention arm that included provision of diaphragm and lubricant and 3.9 percent in the control arm that included only provision of condoms. Findings also showed 158 new HIV infections in the intervention arm and 151 in the control group.
"These results do not support the addition of the diaphragm to current HIV prevention strategies. Condoms remain the only proven barrier method for HIV prevention," said Padian.
All participants in the trial received a comprehensive package of safer-sex and family planning counseling, free male condoms, diagnosis and treatment of curable sexually transmitted infections, and free contraception.
The investigators could not evaluate whether using the diaphragm alone was better than using nothing, because most women in both arms of the trial reported male condom use.
The trial, known at "Methods for Improving Reproductive Health in Africa, or MIRA, began in 2003 and was conducted at sites in Harare, Zimbabwe, and Soweto and Durban, South Africa. The trial was launched because previous data has suggested that the cells in the cervix are particularly vulnerable to HIV infection, and use of a diaphragm presented the potential for protection. A flexible, dome-shaped rubber disk, a diaphragm is inserted vaginally with a gel to cover the cervix.
Collaborating institutions included the University of Zimbabwe-University of California, San Francisco Collaborative Research Program; Medical Research Council, HIV Prevention Research Unit of the (Durban); Perinatal HIV Research Unit, University of the Witwatersrand; and Ibis Reproductive Health.
The study was funded by the Bill & Melinda Gates Foundation.
The UCSF Women's Global Health Imperative (WGHI) provides scientific leadership to help women and girls across the globe protect themselves from HIV/AIDS, sexually transmitted diseases and unintended pregnancies, and to promote safe motherhood.
UCSF WGHI is a program of the AIDS Research Institute at UCSF. The AIDS Research Institute coordinates all of the HIV/AIDS research, treatment, and prevention activities at UCSF. Combining the best basic science, bench-to-bedside research, behavioral studies, direct care services, and policy development, the ARI at UCSF is one of the premier HIV/AIDS medical, education, and research institutions in the world.
UCSF is a leading university that advances health worldwide by conducting advanced biomedical research, educating graduate students in the life sciences and health professions, and providing complex patient care.