For urologists who treat infertility as part of their practice, it is not unusual to be “on call” to harvest sperm from the male partner of a couple undergoing in vitro fertilization (IVF). The timing of sperm harvesting is directly related to the day that egg retrieval of the female partner is going to occur. Some embryologists (who manipulate the sperm in the IVF laboratory and perform intracytoplasmic sperm injection [ICSI]) strongly believe that the sperm should be retrieved from the male partner on the same day that egg retrieval occurs. Conversely, other embryologists have no objection to performing sperm harvesting the day before egg retrieval, particularly if the sperm harvesting procedure is to be testicular sperm extraction (TESE). With TESE the sperm that are extracted from the tubules of the testicular tissue may take a while to obtain motility, which is the main in vitro criterion for choosing which sperm are to be used for the IVF plus ICSI process. By performing TESE the day before egg retrieval, the laboratory personnel allow themselves enough time to dissect the testicular tissue and retrieve the sperm, particularly in the case of nonobstructive azoospermic patients, for whom spermatogenesis may be severely impacted and in whom it may take a long time, relatively speaking, to find sperm in the tissue. However, some embryologists insist that sperm retrieved the day before egg retrieval do not “survive” as well as sperm retrieved the day of egg retrieval.
This inconsistency and variability between IVF laboratories and their embryologists is most likely due to the individual experience of each laboratory rather than any solid, evidence-based data. If it could be demonstrated that harvesting sperm earlier than the day of egg retrieval does not severely impact the ability of the sperm to undergo fertilization, this could make life easier for all concerned because on many occasions the actual day of egg retrieval does not fall on the date originally targeted. In fact, in some cases, the day of egg retrieval may be a week or so later than anticipated at the beginning of the stimulation cycle of the female partner. For urologists harvesting sperm in such a situation, this can play havoc with their daily routine and schedule.
Extended Culture of Human Spermatozoa in the Laboratory May Have Practical Value in the Assisted Reproductive Procedures
Hossain AM, Osuamkpe CO, Nagamani M.
Fertil Steril. 2008;89:237–23817482167
In an attempt to determine whether sperm function is impacted by keeping them in culture for an extended period after retrieval, Hossain and colleagues took 11 semen samples from supposedly normal men and kept them in culture for 7 days. They observed that the only function that significantly decreased after 24 hours was sperm motility, but even this parameter only demonstrated a decrease of approximately 20% (Figure 1). Sperm viability did not significantly decrease, which suggests that the majority of sperm that eventually became nonmotile at 24 hours in culture were still viable.
Figure 1.
Motility, viability, morphology, and membrane integrity patterns exhibited by spermatozoa in culture for 7 days. Values represent the mean ± standard error of 11 samples for each parameter at each time point. Reproduced with permission from Hossain AM et al, Fertil Steril. 2008;89:237–238.
Therefore, this pilot study suggests that sperm harvested from normal patients can be successfully retrieved and stored in culture for at least 24 to 48 hours or possibly longer before egg retrieval without significantly compromising their viability. Although the overall motility of the sperm did decrease after 24 hours, this was by only 20%, with the majority of the sperm still motile by that time. What obviously needs to be confirmed now is whether sperm from oligospermic patients behave in a similar manner. Such an observation in oligospermic men would definitely make life easier for those of us who have to rearrange our schedules on an almost daily basis when an egg retrieval is imminent.