The use of biomarkers of semen exposure in sexual and reproductive health studies.

Biomarkers of semen exposure have been used in studies investigating the safety and efficacy of barrier methods of contraception. They have been used as objective indicators of semen exposure when studying sexual behaviors and in human immunodeficiency virus/sexually transmitted infection research interventions where participants are advised to avoid unprotected sex. Semen biomarkers have also been used to assess or validate self-reported sexual behaviors or condom use in reproductive health settings. Prostate-specific antigen (PSA) and Y chromosome DNA (Yc-DNA) have each been evaluated in the past as semen biomarkers and are the most widely used in the field. While both are considered reliable for evaluating exposure to semen, each has unique characteristics. In this report, we summarize the literature and provide some considerations for reproductive health researchers who are interested in using PSA or Yc-DNA as semen biomarkers. We also synthesize our previous published work on the optimal conditions of collecting and storing specimens and assay performance in the presence of other vaginal products that may influence various assays. Semen biomarkers are innovative and promising tools to further study and better understand women's reproductive and sexual health and behavior. More research is needed to better understand the strengths, limitations, and optimal performance conditions of specific assays in vivo.