Metabolism Might Play A Role In Recurring Miscarriages, Researchers Say

MONDAY, Dec. 22, 2025 (HealthDay News) — Women who have recurrent miscarriages might be suffering from a metabolic problem that affects their ability to sustain a pregnancy, a new pilot study says.

Blood tests of women who’d suffered two or more consecutive lost pregnancies showed that their bodies might have differences in the way they process vitamin B3 (niacin), researchers recently reported in the journal Human Reproduction.

“Every miscarriage is heartbreaking,” lead researcher Harmut Cuny, a senior postdoctoral scientist with the Victor Chang Cardiac Research Institute in Sydney, said in a news release. “Our goal is to understand the biology behind them, so that in time, fewer families have to go through such loss.” 

About 1 in every 50 couples trying to conceive experience recurring miscarriages, researchers said in background notes.

These problems might be tied to nicotinamide adenine dinucleotide (NAD), a biochemical formed by the breakdown of vitamin B3, researchers said.

Earlier mouse studies showed that low NAD levels can cause birth defects and miscarriage, which could be prevented by giving the rodents vitamin B3 supplements, researchers said.

NAD is involved in many essential biological processes that are vital during pregnancy, including cellular energy processing and DNA repair, researchers said.

For the new study, researchers compared 88 women between ages 20 and 40, of whom 37 had a history of recurrent miscarriage.

Blood tests revealed distinct changes in three NAD-related metabolites in those who had experienced repeated losses.

However, these differences occurred whether or not women were taking vitamin B3 supplements, suggesting that a deeper metabolic imbalance might be involved.

Rather than a woman’s NAD levels being too low, changes in how vitamin B3 is metabolized might play a key role, researchers said.

Based on this pilot study, researchers are embarking on a three-year research project to look into NAD-related markers that might indicate a higher risk of miscarriage, and whether supplements or other methods might lower that risk.

“There is an unmet need for biomarkers that allow identification of women at risk of miscarriage to enable early intervention prior to conception and in early pregnancy,” the research team wrote in its paper.

“Given the numerous essential roles of NAD for embryonic development, further research into the role of NAD and related metabolites in miscarriage causation will improve our understanding towards preventative intervention strategies,” the team concluded.

More information

The American Pregnancy Association has more on pregnancy nutrition.

SOURCE: Victor Chang Cardiac Research Institute, news release, Nov. 19, 2025

What This Means For You

A metabolite of vitamin B3 might be involved in women who have repeated miscarriages, researchers say.