How semen exposure may help a mother's immune system accept her partner's baby

The role of semen in induction of paternal-specific tolerance during pregnancy

NIH-funded research University of Washington · NIH-11283925

This project looks at whether contact with a partner's semen helps a pregnant person develop immune cells that tolerate the baby.

Quick facts

Grant typeR01 grant
Study typeNIH-funded research
Funding institutionUniversity of Washington NIH-funded
Lab location1 site (Seattle, United States)
Project IDNIH-11283925 on NIH RePORTER

What this research studies

Researchers will collect samples such as vaginal and cervical tissue, blood, and semen to study how immune cells first encounter paternal antigens. They will examine antigen-presenting cells and tiny particles in semen called extracellular vesicles to see if these carry paternal molecules that promote regulatory T cells. The team will compare immune responses in people with healthy pregnancies to those who develop preeclampsia to look for differences in tolerance. Lab tests will use advanced cell profiling and metabolic analyses to map how tolerance is generated at the mucosal surface.

Who could benefit from this research

Good fit: Ideal candidates are people of reproductive age who are pregnant or planning pregnancy and willing to provide cervical/vaginal tissue or blood samples, and their partners who can provide semen samples.

Not a fit: People who are not pregnant, not planning pregnancy, or whose pregnancy problems are unrelated to immune tolerance mechanisms may not receive direct benefit from this research.

Why it matters

Potential benefit: If successful, this work could reveal mechanisms that help prevent pregnancy complications like preeclampsia and point to new prevention or treatment strategies.

How similar studies have performed: Epidemiological studies and early lab work suggest semen exposure can promote immune tolerance, but the detailed mechanisms in human tissues remain largely unproven.

Where this research is happening

Seattle, United States

Researchers

About this research

  1. This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
  2. Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
  3. For full project details, budget, and progress reports, visit the official NIH RePORTER page below.
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.