I would like to ask about your opinion on sperm counts. I occasionally read alarmistic reports that sperm counts are decreasing all over the developed world compared to some decades ago. I wonder: Are we sure they are, or could it be that the subset of men who volunteer to give their sperm to research just masturbate more often now compared to before the arrival of internet pornography?
I assume that in every decade, only a subset of males will participate in studies of sperm counts. Participating in such a study should mean that one needs to jerk off in a research environment and ejaculate into a container. In every decade, some men will find that task very easy and others will be very uncomfortable with it. So only a subset of all eligible men will volunteer to do it.
That way, researchers will always get test subjects who are more comfortable with masturbation than the average male. The question is: Did that subset of males increase their masturbation rates when the internet made pornography more available? And does masturbating more often deplete sperm counts? (I looked through the internet and got the impression that it at least sometimes does). As a researcher, what is your opinion about this? Could researchers forget to adjust for such a simple source of error, or have I just got something completely wrong?
>does masturbating more often deplete sperm counts?
Sperm counts take 2 – 4 days to recover after ejaculation, whether by masturbation or coitus. In the study I mentioned: https://pubmed.ncbi.nlm.nih.gov/28981654/ they controlled for ejaculation abstinence time. By necessity this was self-reported so it may have been inaccurate, but I don't think it's the main cause.
Furthermore the decrease in sperm counts has been accompanied by an increase in disorders of sexual development (such as hypospadias and cryptorchidism), which suggests to me a developmental cause.
I would like to ask about your opinion on sperm counts. I occasionally read alarmistic reports that sperm counts are decreasing all over the developed world compared to some decades ago. I wonder: Are we sure they are, or could it be that the subset of men who volunteer to give their sperm to research just masturbate more often now compared to before the arrival of internet pornography?
I assume that in every decade, only a subset of males will participate in studies of sperm counts. Participating in such a study should mean that one needs to jerk off in a research environment and ejaculate into a container. In every decade, some men will find that task very easy and others will be very uncomfortable with it. So only a subset of all eligible men will volunteer to do it.
That way, researchers will always get test subjects who are more comfortable with masturbation than the average male. The question is: Did that subset of males increase their masturbation rates when the internet made pornography more available? And does masturbating more often deplete sperm counts? (I looked through the internet and got the impression that it at least sometimes does). As a researcher, what is your opinion about this? Could researchers forget to adjust for such a simple source of error, or have I just got something completely wrong?
>does masturbating more often deplete sperm counts?
Sperm counts take 2 – 4 days to recover after ejaculation, whether by masturbation or coitus. In the study I mentioned: https://pubmed.ncbi.nlm.nih.gov/28981654/ they controlled for ejaculation abstinence time. By necessity this was self-reported so it may have been inaccurate, but I don't think it's the main cause.
Furthermore the decrease in sperm counts has been accompanied by an increase in disorders of sexual development (such as hypospadias and cryptorchidism), which suggests to me a developmental cause.