The decline was 52.4 percent—from 99 million to 47 million sperm per milliliter of semen, said the authors. This was still above the range considered “normal” by the World Health Organization— between 15 million and 200 million sperm per milliliter. The topic is a controversial one, as numerous studies in the past have contradicted one another—some showing a sperm count decline, and others not. This sidesteps the problem of comparing samples measured with incomparable technologies—older tests tended to overestimate sperm count. The best way to confirm changes in sperm count would be through long-term surveillance, known as a prospective cohort study, of a group of healthy males.

Source: Manila Times July 26, 2017 12:22 UTC