Aging is associated with gender-specific hormonal changes that progressively lead to gonadal insufficiency, a condition which characterizes a minority of men and all women. Work-related factors, such as stress and pollutant exposure, affect gonadal function and can interfere with reproduction in both genders. A systematic review of the PubMed, SCOPUS and EMBASE databases was conducted, according to the Preferred Reporting Items for Systemic Reviews and Meta-Analyses (PRISMA) statement to investigate the effect of occupational factors on andropause and menopause. A total of 26 studies met the inclusion and exclusion criteria: 9 studies evaluated the effects of work on andropause symptoms, 8 studies examined its effects on age at menopause onset, and 9 studies addressed its effects on menopausal symptoms. Work-related factors, such as psychological stress, physical effort, and sleep disorders, showed a significant correlation with andropause manifestations, whereas age at menopause and severity of menopausal symptoms were both influenced by factors such as pesticide exposure, high job strain, and repetitive work. Since work accompanies men and women for most of their lives, it is essential to identify and prevent the risk factors that may affect reproductive health.

Steroid hormone levels are closely related to the endogenous circadian rhythm induced by sleep–wake and dark–light cycles. Shift work that disrupts the circadian rhythm may influence the levels of steroid hormones. The association between shift work and alterations in female sex steroid hormone levels has been studied, but little is known about testosterone and its precursor pregnenolone levels in male shift workers. The present study investigated serum pregnenolone and testosterone levels in a group of shift and daytime male workers. All participants were sampled at the beginning of the morning shift. Lower levels of serum pregnenolone and total testosterone were found in the shift workers compared to the daytime workers. Variations in pregnenolone levels may have consequences for well-being, and they might produce consequences for the levels of hormones downstream of the steroid hormone cascade, such as testosterone. The low levels of testosterone found in shift workers demonstrate the perturbative effect of shift work on testosterone serum levels, which may be independent and/or related to pregnenolone synthesis.