Collecting semen samples at home for fertility assessment: time for a new standard?

Background: In fertility clinics the standard approach to semen collection involves a private room close to the laboratory to avoid fluctuations in temperature and to control the time between collection and processing. There are still no firm conclusions whether collecting semen at home has any influence on sperm quality and reproductive competence. The purpose of this study was to assess whether the site of semen collection affects semen parameters. Methods: This retrospective cohort study performed at a tertiary level public fertility center included 8634 semen samples from 5880 men undergoing fertility assessment from 2015 to 2021. The impact of sample collection site was evaluated using a generalized linear mixed model. A subgroup analysis comparing clinic to home collection within the same patient was performed on 1260 samples from 428 men by paired t-test or Wilcoxon Signed Rank Test. Results: Samples collected at home (N.=3240) had significantly higher semen volume, sperm concentration and total sperm count respect to samples collected at clinic (N.=5530) (median (range): 2.9 (0.0-13.9) mL versus 2.9 (0.0-11.5) mL, P=0.016; 24.0 (0.0-252.0) million/mL versus 18.0 (0.0-390.0), P<0.0001; 64.6 (0.0-946.0) million versus 49.3 (0.0-1045.0), P<0.0001, respectively). There was no difference in abstinence period and sperm motility. Paired comparisons of semen characteristics in 428 patients with home-collected (N.=583) and clinic-collected (N.=677) samples confirmed a no negative effect on volume and total sperm count. Conclusions: Our data provide evidence for a not disadvantage with collection at home.