The WHO laboratory manual states that semen specimens produced at home should be delivered to the andrology laboratory for processing within 1 h and be maintained between 20 and 40°C during that time [1]. Reduced sperm motility and viability have been observed over time and at temperature extremes, perhaps due to the accumulation of non-sperm components, such as bacteria or reactive oxygen species [2,3,4, 16, 17]. Importantly, clinic collection, the recommended standard of care for diagnostic samples, maximally ensures the safety and identity of the semen sample. However, the exceptional needs for social distancing during the COVID-19 pandemic have prompted many changes in routine fertility care. Home semen collection is a valuable tool that can enable increased social distancing and patient convenience. Thus, it is crucial to understand whether home semen collection and time over 1 h for travel between collection and processing negatively affects couples’ chances of achieving a usable blastocyst and positive pregnancy test.
Prior studies have evaluated how location of semen collection and length of time from semen collection to processing, with the assumed greater duration and fluctuations in temperature during transport, impact semen analysis parameters and IUI outcomes, with mixed findings [5,6,7,8,9,10, 18]. In the randomized trial conducted by Gao et al., semen analysis results were similar between men who collected at home and at clinic, and patient satisfaction was higher after home collection [6]. Reassuringly, sperm morphology and levels of DNA fragmentation were also similar between the two groups. However, time to processing was not assessed, and these men were not undergoing fertility treatment. In the sole study to our knowledge evaluating semen parameters and embryo outcomes in a large cohort of couples undergoing IVF/ICSI who collected at home versus clinic, the patients chose their collection site and confounders such as maternal age and fertilization method were not controlled [8]. Given the limitations in method and scope of the literature, we aimed to evaluate how both collection location and time between collection and processing affect sperm parameters and embryology outcomes for couples undergoing IVF/ICSI in the exceptional context of the COVID-19 pandemic. Our study suggests that neither home collection nor processing within 2 h of collection is negatively associated with sperm parameters, FR, D5-UQBR, or PR.
Consistent with several other studies, we observed no detrimental effects of home collection, in our total cohort or within the same patient. Amongst conventional IVF cycles, for which changes in motility might have a greater detrimental effect on fertilization, we observed no differences in fertilization rate between the home and clinic groups. While the WHO manual recommends processing within 1 h for home collection of semen analyses, Appell et al. found that the most significant declines in sperm motility and viability at 20 and 37°C occurred beginning 3–6 h after collection [1, 3]. Our findings reinforce these early observations and suggest that motility remains relatively constant at or near body temperature for at least up to 2 h. Any slight changes in motility or sperm quality do not appear to affect early IVF outcomes. On the other hand, reduced stress at home, a proposed reason for superior quality of home collections [7, 19], or positive lifestyle changes during the COVID-19 quarantine, did not improve sperm parameters in our cohort of patients. Of note, we observed a significant increase in forward progression score with longer time to processing in all cycles in both unadjusted and adjusted models. Although statistically significant, an increase in 0.002 progression score is likely not clinically meaningful. This finding may be attributed to the decrease in viscosity of seminal fluid over time [20]. Additionally, in our subgroup of patients with pre- and post-COVID-19 cycles, we observed a marginal increase in fertilization rate with increasing time in the clinic group, as well as a slight but statistically significant improvement in motility, total motile count, and forward progression score with increasing time after home collection, even after controlling for confounding variables. A positive association with time, due to a factor such as reduced semen viscosity, should also be present in both groups, suggesting these observations are likely an artifact of low power. Ultimately, there was no difference in the D5-UQBR. Therefore, more studies are needed to update the literature on how sperm parameters vary over time under specific conditions.
This study has several key strengths. Our IVF laboratory implemented a single protocol change due to the COVID-19 pandemic that allowed us to evaluate the effect of semen collection location and time to processing on sperm parameters and embryology outcomes while ensuring that all other conditions remained consistent between the clinic and home groups over a short period of time. We believe this design reduced the risk of selection bias, though most couples who underwent cycles immediately after the COVID-19 shutdown were potentially lower prognosis individuals intent on restarting fertility treatment as soon as possible. Home collections were all performed with masturbation using the standard collection cup, which avoided the additional confounder of interrupted coitus, which was allowed in the study by Shetty Licht et al. [5]. Our analyses took other key potential confounders into account, including days of abstinence, as this duration has been shown to alter sperm parameters and was not consistently controlled in prior studies [5, 7, 21,22,23]. Another strength of this study is the subgroup analysis of patients with a cycle using clinic collection and a cycle using home collection, illustrating that within the same patient, there was no detrimental effect of home collection. Because these patients served as their own control, this reduced the likelihood of uncontrollable patient-specific variables affecting our results.
The cycles included in our analysis were collected during 2020, and while we included PR data, complete clinical pregnancy and live birth rate data were not available. Our cohort included a small number of conventional IVF cycles, and as fertilization in these cycles may be more susceptible to deterioration in sperm motility or quality, further investigation with a larger number of conventional IVF cycles is warranted. Future studies should also explore whether semen collection and processing conditions have any long-term impact on the offspring in IVF/ICSI cycles. For our subgroup of patients who underwent a cycle prior to and after COVID-19, we did not include a PR comparison, as the majority of these patients underwent a short interval repeat IVF cycle after an unsuccessful prior attempt. The times to processing for home collections varied significantly, which may have reduced our ability to detect certain differences between the home and clinic groups. It is also possible that our home collection findings are not generalizable to other fertility clinic populations or to other seasons (i.e., winter travel conditions). However, given the range in commuting distances across a large metropolitan city that include walking, driving, and train travel, we believe that our population captures a variety of remote collection settings. Furthermore, Song and colleagues found no impact of season on home collection IUI outcomes in their study [10]. Finally, further studies could assess how longer time periods up to 6 h between collection and processing affect sperm parameters and early IVF outcomes.