Sleep disturbances and semen quality in an Italian cross sectional study

In order to obtain information about the relationship between sleep disturbances and sperm parameters, we analyzed data from a study conducted in a Italian Fertility Clinic, in men of couples seeking help for infertility.

Male partners with or without a medical history of reproductive organ diseases (cryptorchidism, varicocele, orchitis, testicular torsion) were eligible for the study. There were 382 men evaluated from May 2014 to November 2016, all of whom completed a self-administered questionnaire on general lifestyle habits. Then all men underwent semen analysis. A total of 382 men aged 26 to 67 years (median age 39 year interquartile range 37-42) were recruited.

A total of 46.3% reported having sleep disturbances. In multivariate analysis, in absence of reproductive organ diseases, semen volume was lower in patients with difficulty in initiating sleep (2.0 ml, IQR 1.5-3.0 vs 3.0 ml, IQR 2.0-3.3, p = .01), whereas in presence of reproductive organ diseases motility A was lower in patients with early morning awakening (25.0%, IQR 15.0-35.0 vs. 40.0%, IQR 30.0-50.0, p = .001). In overweight men, semen volume was lower in patients with difficulty in initiating sleep (2.0 ml, IQR 1.5-3.0 vs 3.0 ml, IQR 2.0-3.0, p = .03). Moreover, among current smokers, patients with difficulty in initiating sleep had semen volume lower (1.5 ml, IQR 1.5-2.5 vs 3.0 ml, IQR 2.0-3.5, p = .0003) and sperm concentration higher (40 millions/ml, IQR 15-60 vs 10 millions/ml, IQR 5-50 p = .03) but total sperm count was not significant different.

Further studies are necessary to elucidate the relationship between sleep quality and semen parameters, which may have important public health implication.