Аңдатпа
Abstract Study question Do occupational exposures in the oil and gas industry and Aktau International Sea Port increase the prevalence of spermatogenesis disorders in Aktau compared to Almaty? Summary answer Aktau’s oil, gas, and port industries expose workers to pollutants, potentially causing oxidative stress, hormonal imbalances, and increased spermatogenesis disorders compared to highly populated Almaty. What is known already Aktau, an industrial hub in Kazakhstan, hosts the oil and gas industry and the Aktau International Sea Trade Port, exposing workers to environmental and occupational hazards. Employees in oil and gas extraction, refining, and transportation face exposure to toxic chemicals, and heavy metals, while port workers encounter fuel emissions and industrial pollutants, all linked to reproductive health risks. One systematic review of 45 studies highlights these risks. Unlike Almaty, which has severe air pollution but higher normozoospermia rates, Aktau’s industrial exposure raises concerns about workplace toxins' impact on male fertility. Even low-dose exposure to pollutants may impair spermatogenesis over time. Study design, size, duration This retrospective comparative study analyzed sperm analysis data collected from October 1 to November 30, 2024, at the in vitro fertilization (IVF) centers “Ecomed” in Aktau and Almaty, with 208 samples from Aktau and 422 from Almaty. Informed consent was obtained from all participants. Participants/materials, setting, methods This retrospective comparative study included 630 men (208 from Aktau, 422 from Almaty) who underwent sperm analysis at “Ecomed” IVF centers between October 1 and November 30, 2024. Men aged 18–55 years with no genetic infertility disorders were included. Samples were analyzed using WHO-validated protocols and CASA. The study examined spermatogenesis disorders in both cities, assessing occupational and environmental exposures. Data analysis used the Chi-Square test, with significance set at p < 0.05. Main results and the role of chance Normozoospermia was observed in 77% of cases in Almaty but only in 13.5% in Aktau. The remaining 86.5% in Aktau had spermatogenesis disorders, including oligozoospermia, asthenozoospermia, teratozoospermia, oligoasthenoteratozoospermia, and azoospermia. Azoospermia prevalence was higher in Aktau (4%) compared to Almaty (2%), suggesting a potential link between industrial exposure and male infertility. The Chi-Square test (p < 0.05) confirmed that these differences were statistically significant, indicating a low probability that the variations occurred by chance, reinforcing concerns about occupational and environmental impacts on reproductive health. Limitations, reasons for caution The study is retrospective and observational, meaning it cannot establish causation, only associations between industrial exposure and spermatogenesis disorders. Data is limited to “Ecomed” IVF centers, which may not represent the entire male population in Aktau and Almaty. Wider implications of the findings The study underscores the importance of male reproductive health screening in industrial regions. Infertility prevention programs should consider environmental and occupational risk factors in addition to lifestyle and genetic influences. Trial registration number No