Semen quality in Asturias leads Spain with highest sperm concentration and motility, study finds

A study published in Archives of Medical Research has revealed that Asturias leads Spain in semen quality.

Men in the region have the highest sperm concentration (59.8 million/mL), total motility (54.3%) and total motile sperm count.

The research, which analysed 2,329 samples across 12 regions, suggests that environmental and lifestyle factors may influence these differences.

A study published in Archives of Medical Research and presented at the congress of the European Society of Human Reproduction and Embryology (ESHRE), analysed semen samples from 2,329 men undergoing fertility studies between February and October 2022. The research was led by biologist Rocío Nuñez Calonge. The researchers found that men studied in Asturias had the highest sperm concentration —59.8 million sperm per millilitre on average—, the highest total motility (54.3%), and the highest total number of motile sperm. These results were statistically significant compared to other regions, such as Granada, Alicante and Madrid, which recorded the lowest values.

BEYOND THE LABORATORY: A ROBUST METHODOLOGY

All analyses were performed using exactly the same laboratory protocol and under internal and external quality controls, reducing the possibility that the observed differences were due to methodological variations between centres. Previous studies on geographical differences in semen quality often compare results obtained in different laboratories with different procedures. In this case, the twelve centres used standardised protocols and participated in a common quality control programme, so the authors consider it unlikely that the differences were due to measurement errors. The study also found no differences between regions in the age of participants or in the days of sexual abstinence prior to sample collection, two factors that can influence semen analysis results.

WHY DOES THIS HAPPEN? HYPOTHESES AND LIMITATIONS

The research does not identify the cause of these differences, although the authors suggest several hypotheses. These include the influence of environmental factors, such as temperature, altitude or exposure to pollutants, as well as lifestyle habits that could vary between territories. Previous studies have linked high temperatures, exposure to certain chemicals and other environmental factors with poorer semen quality. However, the researchers stress that their study cannot demonstrate this relationship because it did not have individual information on smoking, alcohol consumption, body mass index, educational level or other factors that also influence male fertility. The authors also emphasise that all participants attended assisted reproduction clinics for a fertility evaluation, so the results do not necessarily represent all Spanish men. Furthermore, the study is observational, which prevents establishing cause-and-effect relationships.

For InasTour, the results of this study add a new dimension to the appeal of Asturias as a place to live. The quality of the environment, the climate and the lifestyle in the region are factors that not only contribute to well-being but may also have a positive impact on health, which is a key consideration for international buyers and families seeking a healthy environment in which to settle.

This is the first national study to compare semen quality between different Spanish regions using a homogeneous methodology in all centres, providing solid evidence that there are geographical differences that merit further investigation.

The study published in Archives of Medical Research places Asturias at the top of the ranking for semen quality in Spain, with significantly better results in sperm concentration, motility and total motile sperm count. Although the causes of these differences are still unknown, the study highlights the importance of environmental and lifestyle factors. This finding adds to the list of attributes that make the region a privileged place to live and invest, where quality of life and health seem to go hand in hand with the natural environment and the local culture.