The quality of the sperm is higher in the north of the State

BarcelonaThe quality of semen in men from northern Spain is higher than that of men from the center and south of the country, despite similar lifestyles. This is the conclusion of a study presented this Tuesday at the 42nd Annual Meeting of the European Society of Human Reproduction and Embryology (ESHRE), which links these differences to higher exposure to environmental contaminants. "Given the widespread presence of air pollution in many urban environments, its possible effects on male fertility deserve further investigation," argues Professor Rocío Núñez-Calonge, lead author of the study published in the journal Human Reproduction. To reach these conclusions, they analyzed the semen quality and lifestyle of 386 men who underwent a fertility assessment at seven assisted reproduction centers in Spain between June 2024 and December 2025. Factors such as place of residence, body mass index (BMI), medical history, physical activity, exposure to chemicals, medication use, smoking, alcohol, drugs, and coffee consumption were taken into account. The results revealed significant regional differences in semen volume, sperm concentration, motility, morphology, and total motile sperm count. The prevalence of asthenozoospermia (reduced sperm motility) and teratozoospermia (abnormal sperm morphology) was also considered.

According to the results, men living in northern Spain recorded higher semen quality overall, with an average total motile sperm count of 94.35 million, compared to 50.11 million in central Spain. The northern region also had the highest average sperm concentration (80.96 million/ml), and reduced motility affected 23.9% of men in the north, compared to 55.4% in southern Spain and 53.4% in central Spain.

Investigate environmental contaminants

Despite these differences, the participants' lifestyle was similar, which is why the authors believe that the impact of pollution on male fertility needs to be further investigated. For Núñez-Calonge, these conclusions could have implications beyond Spain, as studies from various countries report significant regional variations in semen quality. Therefore, she insists that broader and well-designed research is needed to better clarify the relationship between environmental exposure and sperm quality. "At the same time, stronger public health policies aimed at reducing exposure to contaminants, industrial chemicals, and plastic-derived compounds must be considered a priority to protect reproductive health in future generations," reasons the expert.