Although it is still a controversial issue, obesity is increasingly related to fertility problems in men, always in relation to seminal quality. And, in fact, it has joined the list of risk factors for male infertility, along with tobacco, alcohol, drug use, exposure to toxic agents, some diseases, or treatment with certain medications.

However, the only thing that has been shown so far is that being overweight (defined by a body mass index (BMI) greater than 25) and waist circumference are directly related to lower seminal volume and lower sperm concentration. But no conclusive evidence has been obtained of how it affects their motility and morphology.

The truth is that the semen of obese men have a lower presence of testosterone and other hormones than those who are not overweight, which can be related to a decreased testicular function (hypogonadism) that would negatively affect the parameters that determine male fertility: DNA concentration, motility, morphology, and fragmentation.

A study carried out at Stanford University in which the semen of the men of 468 couples who wanted to have a child was analyzed has determined that the BMI and the waist circumference negatively influence the volume of ejaculation and the number of sperm per milliliter of semen. Men with a waist greater than 100 centimeters had a seminal volume 22% lower than that of those with a normal perimeter, in the same way, that in those with morbid obesity this was, on average, 2.8 milliliters, compared to 3.3 of normal weight.

However, by themselves, these data do not say much, since a seminal volume of between 1.5 and 5 milliliters is considered normal. Furthermore, this study has not detected any relationship between BMI and waist circumference with a higher or lower sperm concentration, a reduced vitality of the sperm, or an increase in malformed sperm.

In fact, some of the men included in the study had previously had at least one child. By way of conclusion, therefore, sexologist in Delhi could only ensure that obesity can influence the degree of male fertility, but it does not establish a cause-effect relationship between excess weight and infertility.