Altitude ascent: Exploring the unknown terrain of women’s reproductive health

High-altitude (HA) environments pose significant challenges to human survival and performance due to the physiological effects of hypoxia. Studies have indicated that hypoxia can impact reproductive health and fertility both in vitro and in vivo , although the results have often been inconsistent. One of the key mediators of hypoxia-induced physiological responses is nitric oxide (NO), recognised as a vital factor in female reproductive health, but either excessive or insufficient NO levels can affect various reproductive processes. Despite extensive research on male and female natives at high altitudes, a notable gap persists in studies of female sojourners or mountaineers, suggesting a potential decline in reproductive health among these groups. This review focuses on changes in reproductive hormones, increased NO, complications during pregnancy, disruption of circadian rhythm and alterations in NO and protein expression in women who visit or reside in HA areas. These insights aim to open new paths and direct future research, providing a deeper understanding of reproductive challenges and promoting possible solutions for visitors and natives of HA.