Seasonal AMH variability implies a positive effect of UV exposure on the deterioration of ovarian follicles

Anti-Müllerian hormone (AMH) is produced exclusively by granulosa cells of ovarian follicles and is an indicator of ovarian reserve which declines with age. Seasonality in AMH levels have been reported to be correlated with variations in Vitamin D levels, which is dependent on sunlight exposure. However, the effects of age and its association with solar radiation intensity with respect to AMH was never studied before. In this study, we investigated the relationship between AMH levels with season and with solar radiation intensity in a cohort of 2235 women aged 19–40 years undergoing hormonal work-up over a four-year period. Our findings revealed that among women aged 20–29 years, there was no significant association between AMH levels and either season or solar radiation intensity. However, for women aged 30–40 years, a seasonal pattern was observed, with higher AMH levels during spring and autumn months characterized by moderate solar radiation intensity. Women in their declining ovarian reserve age were found to be more sensitive to the effects of moderate solar radiation. Moderate solar radiation exposure positively impacted AMH levels, whereas low and high intensity exposure had a negative effect. Our findings indicate that age and solar radiation intensity must be considered when assessing AMH levels and provide valuable insights into the intricate relationship between AMH, seasonality, and UVB exposure in the context of reproductive health.