HORIZONS PROJECT
Validation of the Accuracy of Prostate-specific Antigen Detection in Vaginal Fluids Obtained by Self-sampling as a Marker of Semen Exposure and Condom Failure

Male and female condoms are the only methods known to provide dual protection against unintended pregnancy and HIV and some sexually transmitted infections (STIs). For sexually active individuals, correct and consistent condom use is an important means for reducing the risk of HIV infection and other STIs, such as chlamydia and gonorrhea. While there is good evidence that the female condom is effective in pregnancy prevention and some evidence that it is effective against STI transmission, it is still unclear whether it is as effective as the male latex condom.

Horizons researchers in Brazil are conducting a study to examine the validity of the use of prostate-specific antigen (PSA) as a sensitive biomarker for semen exposure during sexual intercourse. Specifically, this study will:

1. Assess the accuracy of PSA detection after intravaginal exposure to known amounts of semen, comparing self-collected samples and samples taken by a trained nurse.
2. Assess the reliability of self-sampling for PSA detection, comparing the results with samples taken by a trained nurse, after intercourse using a male or female condom.

For the first study objective, 100 sexually active married women attending the family planning clinic of the University of Campinas will be enrolled in the study. For the second study objective, 100 additional sexually active eligible women at the Family Planning Clinic will be enrolled. The levels of PSA in the vaginal fluids obtained from the two different sampling techniques will be compared. The comparisons will be made for samples collected after sexual intercourse with a female condom and with a male condom.

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Location

Campinas, SP, Brazil

Duration

July 2006–June 2007

Horizons and Population Council researchers

Waimar Tun, Juan Díaz, Johannes van Dam

Non-Council collaborators

Luis Bahamondes (Department of Obstetrics and Gynecology, University of Campinas)

Centro de Pesquisas em Saúde Reprodutiva de Campinas

Donor

US Centers for Disease Control and Prevention

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See Also

• Brazil

• HIV and AIDS/Prevention

• Reproductive Health/Contraception

• Reproductive Health/Reproductive Tract Infections and Sexually Transmitted Infections

• Horizons Program

• Frontiers Program

• Ebert Program on Critical Issues in Reproductive Health

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