Small Penis Study Controversy

Many men were horrified recently when the media began running sensational headlines indicating that men with smaller penises were less likely to be able to have children. These headlines were based on a study presented at the 2018 American Society for Reproductive Medicine conference; however, they are a complete distortion of the study’s actual findings.

The Study

The actual study was conducted on a convenience sample of 815 men who presented to a men’s health clinic from 2014 to 2017. The doctors routinely measured the stretched, flaccid penile length of the men as part of their health workup. The doctors stated that they believe stretched penile length is a good indication of erect penile length, which can be difficult to directly measure in a clinical setting. They found a statistically significant difference in penile length between the men who were found to be infertile and the men who were not; however, the average difference was only 1 cm, or 0.4 inches.

Problems with the Study

One problem with this study is the source of the patients and the method used to enroll them; they only enrolled men who presented at a men’s health clinic, suggesting the patients studied are not representative of the general population, instead being a group of men who were suffering from various types of reproductive issues.

The biggest problem with this study, however, is the media interpreting its results to mean that a shorter penis length was the cause of the men’s infertility. All the study showed was that there was a correlation between the two factors, and a famous phrase that is often used in scientific research is that correlation does not mean causation. In fact, in this group of men, it is much more likely that an underlying hormonal or genetic factor was the cause of both the infertility and the shorter penis.

Other scientists have speculated that exposure in utero to a class of chemicals called phthalates, which are found in plastics and currently have reached high levels in the environment and in human bodies, can affect the development of the male reproductive system. Thus, exposure to these chemicals as a fetus could lead to both infertility and a shorter penis.

Talk to Our Expert

We would like to repeat: having a shorter penis does not mean you are infertile. However, if you are worried about your penis size or your fertility, please don’t hesitate to get in touch with the office of Mark P. Solomon, MD, with locations in Beverly Hills, CA and Bala Cynwyd, PA. Contact us today to book a consultation and learn more!