Gum disease may impair female fertility and egg quality – study

Gum disease may impair female fertility by triggering inflammation that affects the ovaries and egg quality, a study in mice suggests.

The findings point to a possible biological link between oral health and unexplained infertility.

Researchers said chronic oral inflammation was linked to oxidative damage, disrupted follicle development and reduced live birth rates in mice.

The study was led by prof Michael Klutstein at the Hebrew University of Jerusalem and prof Asaf Wilensky at the Hebrew University-Hadassah Medical Center, with students Dr Paz Kles and Stephen Ameho.

Scientists examined inflammation linked to dental implants in a mouse model, a common clinical scenario, meaning the research was carried out in animals rather than people.

They tracked how immune signals moved through the body and found the inflammation did not appear to stay confined to the mouth.

Instead, it triggered a systemic immune response, meaning an immune reaction across the body, that reached the ovaries.

The animals had increased levels of inflammatory cytokines in the ovaries. Cytokines are proteins used by immune cells to send signals during inflammation.

Researchers also found changes in immune cell populations, oxidative damage to ovarian tissue, impaired follicle development and reduced oocyte quality.

Oxidative damage happens when harmful molecules damage cells. Oocytes are immature egg cells, while follicles are small structures in the ovaries that contain developing eggs.

These biological changes were linked to reduced live birth rates under inflammatory conditions.

The study also found that oocytes showed DNA damage and epigenetic alterations similar to those seen in reproductive ageing.

Epigenetic changes affect how genes behave without changing the underlying DNA code.

Prof Klutstein said: “Inflammation is often thought of as a localised response, but our findings show that it can have systemic consequences that extend as far as the reproductive system.

“This work suggests that chronic oral inflammation may be an underrecognised factor in female infertility, potentially contributing to cases that currently have no clear explanation.”

The researchers said the findings add to growing evidence linking oral health with overall health.

Chronic oral inflammatory conditions, such as periodontitis, are widespread and have previously been associated with systemic diseases.

Periodontitis is a severe form of gum disease that can damage the tissue and bone supporting the teeth.

The authors said further research in clinical settings would be needed to understand whether the findings translate to patient care.

If confirmed in humans, they said the work could support new approaches to diagnosis and treatment, including anti-inflammatory or antioxidant strategies aimed at improving fertility outcomes.