Temporal trend of conventional sperm parameters in a sicilian population in the decade 2011–2020

Abstract

Objective: To evaluate the changes of conventional sperm parameters in men who referred to an andrology reference center in Catania (Eastern Sicily, Italy) in the decade 2011–2020. Methods: For this purpose, we selected–retrospectively and randomly–the reports of 1409 semen analyses performed according to the 2010 WHO criteria. Data on sperm concentration, total sperm count, progressive sperm motility, and percentage of normal forms were analyzed using linear regression of the raw and logarithmic-transformed data. The sperm parameters were subsequently pooled in two five-year periods (2011–2015 and 2016–2020) and compared with each other. Finally, the influence of the city of residence was assessed on five-year pooled data. Main results: A slight but non-significant decline of total sperm count (−2.26 million/year; p = 0.065) and the percentage of spermatozoa with normal morphology (−0.08%/year; p = 0.057) was observed. In contrast, a significant increase of progressive sperm motility (+0.28%/year; p = 0.008) over time was found. The total sperm count of the quinquennium 2016–2020 was significantly lower. and an upward trend of progressive sperm motility was found. compared to the years 2011–2015. No changes in sperm concentration and morphology occurred in the years 2011–2015 vs. 2016–2020. Sperm conventional parameters did not differ when the five-year pooled data were analyzed according to the town of residence. Conclusions: Divergent trends of total sperm count and progressive sperm motility over time were found in patients from Eastern Sicily. This may point out the need of assessing whether a time-dependent change of biofunctional sperm parameters occurs to really understand the trend of sperm quality over time.