photo credit: HeyRocker

For the past two decades, popular media has told us that the average male sperm count has dropped dramatically. We’re told that various environmental factors, including things like plastics, pesticides, or hormones used in our food supply have created significant dangers for men. We’ve been told that these factors act like estrogen in men’s bodies, decreasing sperm supply.

This all started with one report. The report, released back in 1992, told us that sperm counts had decreased by 50 percent from 1938 to 1991, and that the trend was going to continue. That single study had a huge impact, being cited in more than a thousand other scientific journal papers.

Now, to be sure, there were researchers who have criticized the report. They suggest that the quality of the data, as well as no standardization in semen collection methods and other factors, corrupted the data. Because the results were so dramatic, they caused people to panic, regardless of whether they were scientifically sound. Other studies that followed contradicted the original results.

Now, the same Danish group that did the original study has some new data based on 15 years of additional study, this time with more scientific controls in place. The new data seems to suggest that sperm counts are not on the decline, at least over the past 15 years. The data show fairly standard sperm count levels for the past decade and a half.

What does this tell us? Well, for starters, it shows us how one single study can have a tremendous impact on society. It’s not uncommon for an idea like this to spread like wildfire.

It also tells us that more research needs to be done in this area. After all, whether sperm counts are truly declining is a hugely important issue. And, it may well be that there are environmental factors that can cause a decline in sperm count. However, we need to be sure that this is the case, through consistent, proven research results, rather than listening to every scary bit of fertility news that comes across the wire.

This entry was posted on Wednesday, June 8th, 2011 and is filed under Fertility.