JBRA Assisted Reproduction 2025;29(Suppl.2 SBRA 2025):147
Poster Presentation
29^th Annual Congress of the SBRA. São Paulo/SP - Brazil, 2025
doi: 10.5935/1518-0557.20263942

P-135. Impact of microplastics on male fertility: a comprehensive re view of potential harmful effects

Catarina Favero Monteiro Pinheiro¹, Gabrielle Gonçalves Oliveira¹, Gabriel Monteiro Pinheiro¹, Julia Roverso Correa Silveira¹

¹ Universidade Santo Amaro - São Paulo - SP - Brasil

Objective: Considering the increasing prevalence of microplastics in the environment and their emerging threat to human reproductive health, this review aims to comprehensively analyze current data on microplastic-induced male fertility impairment, elucidate the toxicological mechanisms involved, and highlight the critical need for accelerated research and policy action
Methods: This narrative review included studies published between 2010 and 2025, identified through PubMed and Web of Science using the keywords "microplastic," "reproductive system," "male fertility," and "infertility." After screening 45 records and applying predefined inclusion criteria, we selected studies focusing on human fertility and microplastic-related reproductive toxicity. Low-quality studies and those based solely on animal models were excluded. The selected articles were critically analyzed to synthesize current knowledge and identify research gaps. In total, eight articles met the inclusion criteria.
Results: Semen quality has declined significantly over the past 80 years, potentially due to environmental pollutants caused by industrialization. Microplastics (MPs) are plastic particles smaller than 5 mm, generated by the degradation of larger plastic products, and are widely distributed in the environment, including air, water, soil, and the food chain. Besides carrying toxic additives used in plastic manufacturing, MPs can accumulate in human tissues and cross biological barriers, raising growing concerns about their potential effects on fertility, pregnancy, and long-term health. Emerging evidence suggests that MPs may play a role in the observed decline in male reproductive health. A recent study provided the first direct evidence of microplastic contamination in the human male reproductive system. MPs were detected in six testicular and thirty semen samples, with polystyrene being the most prevalent polymer in testicular tissue (67.7%), while polyethylene and polyvinyl chloride predominated in semen. Another study evaluating 18 male seminal fluid samples found MPs in 55% of them. Polytetrafluoroethylene was the most prevalent polymer, detected in 41% of the samples. Other identified polymers included polystyrene (14%), polyethylene terephthalate, polyamide (5%), and polyurethane (5%). To assess the potential impact of MPs on male fertility, researchers exposed 98 human semen samples to increasing concentrations of polyvinyl chloride for six hours. Exposure resulted in a significant reduction in sperm motility, accompanied by increased oxidative stress and DNA fragmentation—demonstrating a clear toxic effect of MPs on sperm function. Additionally, a meta-analysis involving 1,200 male patients undergoing infertility diagnostics detected microplastics in 68% of testicular tissue samples. Men with MP contamination exhibited significantly lower sperm counts compared to those without, along with histopathological evidence of inflammation, oxidative damage, and disruption of the seminiferous epithelium. Studies suggest MPs impair reproductive health via multiple biological mechanisms. Oxidative stress appears to be a central mechanism. MPs promote overproduction of reactive oxygen species (ROS), leading to sperm DNA damage, reduced motility, and granulosa cell apoptosis, ultimately affecting spermatogenesis and gamete quality. Disruption of the hypothalamic–pituitary–gonadal (HPG) axis is also suggested as a potential contributing factor. Exposure to MPs may alter the secretion of key reproductive hormones, such as FSH, LH, and testosterone, potentially disrupting gonadal maturation and hormonal balance.
Conclusion: Current evidence indicates that microplastic (MP) exposure has the potential to adversely affect male fertility, primarily through mechanisms involving oxidative stress and endocrine disruption. Although data from human studies remain limited, converging finding, including diminished sperm motility, endocrine alterations, and histopathological damage, underscore the imperative for further high-quality research. In view of the pervasive distribution of MPs and their propensity for bioaccumulation, the advancement of scientific investigations and the implementation of targeted public health interventions are essential to preserve reproductive health and mitigate potential long-term consequences for future generations.