Of course. Different scientists have verified that those men with a body mass index greater than 30 have a poorer semen quality and, therefore, have greater difficulties when it comes to being able to achieve pregnancy naturally.
The reason for this is that overweight men tend to have low levels of androgens, such as testosterone. As a consequence of this decrease in male sex hormones, spermatogenesis, that is, the production of sperm is affected.
Therefore, men with a high BMI may present with oligozoospermia, and alteration of the semen characterized by a low concentration of sperm.