P-214 Obtaining a fresh sperm sample for Delayed-ICSI: Does it matter?
Authors: Sam J.P , Gan S.K , Lee C.S.S 
Published: June 2022

Abstract

Study question
Is a fresh sperm sample for Delayed-ICSI necessary to improve cycle outcomes?

Summary answer
Our results have demonstrated that the use of fresh sperm for Delayed-ICSI does not have any influence on outcomes compared to using 1-day-old sperm.

What is known already
Delayed-ICSI is a procedure whereby immature oocytes on Day0 are cultured overnight and injected the next day (Day1, if mature). When Lundin et. al.  (1996) compared the use of fresh sperm versus 1-day-old sperm for Rescue-ICSI on unfertilised oocytes, a higher fertilisation rate was found when fresh sperm was used. At Alpha IVF & Women’s Specialists (AIWS), Delayed-ICSI is carried out using 1-day-old (overnight) sperm obtained on Day0. Therefore, in order to affirm Lundin et. al.’ s findings, a comparison between the fresh and overnight sperm samples for Delayed-ICSI was done, and the outcomes were analysed.

Study design, size, duration
From January to July 2021, 187 IVF cycles with Delayed-ICSI on Day1-matured oocytes were done in AIWS. Of which, 89 cycles used overnight sperm – semen collected on Day0, which were processed for ICSI (Group A – mean maternal age: 37.3; age range 29.0-47.0) while the remaining 98 cycles used fresh sperm – semen collected on Day1, which were also processed for ICSI (Group B – mean maternal age: 37.9; age range 19.0-46.0).

Participants/materials, setting, methods
Semen samples were processed using density gradient centrifugation and/or swim-up. Day0-ICSI was done on all matured oocytes at 2.5-4.5hours post-retrieval (PIEZO, Japan). Immature oocytes were further cultured for 18-24hours and Delayed-ICSI was done immediately after maturity assessment with either overnight (Group A) or fresh sperm (Group B). All injected oocytes were cultured up to 7 days and trophectoderm biopsy for PGT-A screening (IonTorrent, USA) was performed on selected blastocysts prior to vitrification (Cryotec, Japan).

Main results and the role of chance
In Group A, the normal fertilisation (2PN), abnormal fertilisation (&gt;2PN), blastulation, blastocyst utilisation and euploidy rates of Delayed-ICSI were 64%, 14%, 34%, 17% and 33% respectively. In Group B, the normal fertilisation (2PN), abnormal fertilisation (&gt;2PN), blastulation, blastocyst utilisation and euploidy rates of Delayed-ICSI were 52%, 21%, 36%, 13% and 30% respectively. No statistical significance was observed in the fertilisation (2PN) (p = 0.2588), abnormal fertilisation (&gt;2PN) (p = 0.0978), blastulation (p = 0.9067), blastocyst utilisation (p = 0.5101) and euploidy rates (p = 1.000) between Group A and Group B.
Our findings showed that a 18-24hour incubation of sperm (1-day-old spermatozoa) had no influence on their fertilisation potential and the subsequent embryo development when compared to freshly prepared sperm for Delayed-ICSI. Furthermore, PGT-A analysis also revealed that overnight sperm do not contribute to an increase in chromosomal abnormalities in a blastocyst derived from Delayed-ICSI.

Limitations, reasons for caution
A larger patient cohort would have provided more data for the study, therefore further studies are required to validate our findings. Additionally, the effect of overnight incubation on the genetic and metabolic quality of a spermatozoa can also be studied to support our results.

Wider implications of the findings
The findings of this study have shown that fresh sperm samples on Day1 is not required as no significant differences in outcomes were observed between the use of fresh versus overnight sperm samples for Delayed-ICSI.

Trial registration number
Not applicable