P-022 The ICSI Outcome of Frozen Thawed Testicular Sperm Utilization in Azoospermic Men with AZFc Microdeletion
Authors: Bakırcıoğlu D E , Özcan C , Tosun S , Bayazit N , Cengiz S , Uluğ U 
Published: June 2023

Study question

What is the efficacy of frozen thawed surgically retrieved spermatozoa in azoospermic men with AZFc microdeletion undergoing Introcytoplasmic sperm injection (ICSI)?

Summary answer

The comparison between frozen thaw to fresh testicular sperm did not show statistically significant difference in terms of fertilization, blastocyst development and pregnancy rates.

What is known already

In male infertility, Y chromosome microdeletion (YCM) may be the cause up to 10% of men with oligozoospermia or azoospermia. AZFc region deletion was mostly detected in YCM. In men with azoospermia and AZFc deletion spermatozoa can be retrieved via testicular sperm extraction (TESE). Today, couples suffering azoospermia due to AZFc deletion may have genetically own child by using testicular sperm with ICSI. Because of the rare incidence of AZFc deletion, the outcome of ICSI cycles in which frozen thawed spermatozoa utilized for assisted conception has not been widely known.

Study design, size, duration

The data of 611 men with non-obstructive azoospermia (NOA) who underwent microTESE surgery between 2014 and 2022 was retrospectively analyzed. Assisted reproduction treatment (ART) outcome of couples whose men with AZFc deletion was further analyzed according to the fresh or frozen thawed spermatozoa usage for ICSI.

Participants/materials, setting, methods

All of the patients were genetically screened with karyotype and Y chromosome microdeletion analysis and microTESE operation was performed for testicular sperm recovery. The patients who diagnosed AZFc deletion and had successful sperm recovery divided to two groups according to cryopreserved or fresh sperm utilization for ICSI. The spouse and men age, fertilization rate, blastocyst development, pregnancy and live birth rate was compared between the groups.

Main results and the role of chance

Twenty-seven (4.4%) men were diagnosed YMC deletion in total of 611 men with NOA who underwent microTESE. Spermatozoa was successfully retrieved in 14 men (51.8%) men who were diagnosed AZFc deletion. The mean age of women and men were 30.5 (3.5) and 32.8 (4.1) years, respectively. Oocyte retrieval and ICSI were accomplished in 18 cycles. In 7 (38.8%) cycles fresh testicular spermatozoa and in 11(61.2%) cycles frozen thawed testicular spermatozoa were used. In one cycle, embryo transfer was cancelled due to total fertilization failure. In total, fertilization rate as 2PN/M2 oocytes was 57% (119/206). In 5 cycles cleavage stage embryos were transferred whereas in remaining 13 cycles blastocysts were transferred. Blastocyst development rate as day 5 blastocyst/2PN was 45.2% (42/95). Comparison of fertilization and blastocyst development rates according to fresh TESE spermatozoa and frozen thawed TESE spermatozoa groups were 63.2% vs 54.4% and 50.0% vs 38.7% respectively (p &gt; 0.5 for both). Clinical and live birth rates per embryo transfer cycle were 57.1% vs 40.0% and 42.8% vs 30.0% respectively (p &gt; 0.5 for both).

Limitations, reasons for caution

Fresh and frozen thawed groups demonstrated no statistical difference in terms of ICSI outcome. However, relatively reduced fertilization and blastocyst development rates should be interpreted cautiously because beta type error. Further data is needed to clarify this difference.

Wider implications of the findings

The best of our knowledge our study is the largest in literature comparing frozen thawed and fresh sperm utilization for ICSI in men with AZFc deletion. This data may help for physicians and couples to give decision diagnostic microTESE surgery and cryopreservation of sperm further ICSI treatment.

Trial registration number

Not applicable