Infertility Among Commercial Shuttle Bus Drivers in Onitsha Urban Nigeria: The Role of Testosterone Dysregulation and Occupational Heat Stress in Onitsha Metropolis, Southeastern, Nigeria

Male infertility has emerged as a growing public health concern globally, particularly in occupational groups exposed to environmental and physiological stressors. This study investigated testosterone dysregulation and infertility risk among commercial shuttle bus drivers in Onitsha metropolis, Southeastern Nigeria. A cross-sectional analytical study involving 180 participants (120 commercial shuttle bus drivers and 60 age-matched controls) was conducted between January and October 2025. Serum testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), cortisol, and semen parameters were assessed using ELISA and WHO semen analysis protocols.