Significant decline in sperm count globally, including India, may threaten human existence

New Delhi: An international team of researchers has found a significant decline in sperm counts over the years in many countries globally, including India. Sperm count is an indicator of human fertility. However, it also is a sign of men’s health.

Low level sperm count can lead to chronic disease, testicular cancer and a decreased lifespan, the researchers said. The decline reflects a global crisis related to modern environment and lifestyle, with broad implications for the survival of the human species, the researchers said. The study was published Tuesday in the journal ‘Human Reproduction Update’.

The research used data from 53 countries. It includes an additional seven years of data collection (2011-2018) and focuses on sperm count trends among men in regions not reviewed previously, specifically South America, Asia and Africa. The data shows, for the first time that men in those regions share the significant decline in total sperm counts (TSC) and sperm concentration (SC).

This was seen previously in North America, Europe and Australia. The study shows an accelerated post-2000 decline in TSC and SC globally. “India is part of this larger trend.

In India, due to availability of good data (including 23 estimates in our study, one of the countries with the richest data), we have more certainty that there is a strong and sustainable decline, but it’s similar globally,” Professor Hagai Levine of Hebrew University of Jerusalem in Israel told this agency. “Overall, we’re seeing a significant worldwide decline in sperm counts of over 50 per cent in the past 46 years. It is a decline that has accelerated in recent years,” Levine added.

The current study did not examine the causes of sperm count declines. Levine however, pointed to recent research indicating that disturbances in the development of the reproductive tract during fetal life are linked to lifetime impairment of fertility and other markers of reproductive dysfunction. “Additionally, lifestyle choices and chemicals in the environment are adversely affecting this fetal development,” Levine explained.

“Our findings serve as a canary in a coal mine. We have a serious problem on our hands that, if not mitigated, could threaten mankind’s existence. We urgently call for global action to promote healthier environments for all species and reduce exposures and behaviours that threaten our reproductive health,” Levine asserted.

The scientist noted that a separate study in India should be done, better by following the same population over time. “However, there is no reason to think the trend in India is different,” Levine informed. Professor Shanna Swan at the Icahn School of Medicine, Mount Sinai, US, stressed that low sperm count do not only affect men’s fertility, but have serious ramifications for men’s health more generally, and are linked with other adverse trends, termed together as testicular dysgenesis syndrome.

“The troubling declines in men’s sperm concentration and total sperm counts at over one per cent each year as reported in our paper are consistent with adverse trends in other men’s health outcomes, such as testicular cancer, hormonal disruption, and genital birth defects, as well as declines in female reproductive health,” Swan said.  .