#AI reads Urine# Identification of potential NAD-related biomarkers of recurrent miscarriage risk
Published 16 November, 2025
This study focused on non-pregnant women aged 20–40 years, comparing NAD-related metabolites between 37 women with a history of recurrent miscarriage (at least 2 consecutive spontaneous miscarriages before 20 weeks of gestation) and 51 women without such a history. It was found that in women with a miscarriage history, the levels of three NAD salvage pathway excretion products (1MNA, 2PY, and 4PY) in whole blood, plasma, and urine, as well as nicotinamide (NAM) in urine, were significantly elevated. Among these, plasma 1MNA was directly associated with miscarriage risk—for every 1-unit increase in plasma 1MNA, the risk of miscarriage rose by 2%—and these associations were independent of age and vitamin B3 supplementation. When combining 1MNA, 2PY, 4PY, and age for prediction, the accuracy reached 89%.
Notably, the biomarkers in urine played a prominent role: not only could 1MNA, 2PY, 4PY, and NAM in urine effectively distinguish between the two groups of women, but urine samples also offered distinct advantages—they are easy to collect and process, require no invasive procedures, and after creatinine normalization, the levels of key biomarkers in random urine samples were consistent with those in 24-hour urine samples (which better reflect full-day excretion). This makes urine a convenient and feasible sample option for recurrent miscarriage risk assessment, while also confirming the association between abnormal NAD metabolism and recurrent miscarriage.
Hum Reprod. 2025 Oct 31:deaf195. doi: 10.1093/humrep/deaf195.
Youhe Gao
Statement: During the preparation of this work the author(s) used Doubao / AI reading for summarizing the content. After using this tool/service, the author(s) reviewed and edited the content as needed and take(s) full responsibility for the content of the published article.
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