Outcomes with intracytoplasmic sperm injection using fresh vs. frozen elongated spermatids from microsurgical testicular sperm extraction

Objective To evaluate the reproductive outcomes of intracytoplasmic sperm injection using fresh and frozen-thawed elongated spermatids obtained from microsurgical testicular sperm extraction from men with non-obstructive azoospermia. Design Retrospective cohort study. Subjects A total of 256 infertile men underwent one or more mTESE procedures between 2004 and 2017, with the intention of attempting to conceive via intracytoplasmic sperm injection with their female partners. Exposure Intracytoplasmic sperm injection was performed using fresh or frozen-thawed elongated spermatids. Main Outcome Measure(s) Sperm retrieval rate, fertilization rate, blastulation rate, having an embryo transfer, positive beta-human chorionic gonadotropin level, clinical pregnancy rate, live birth rate, miscarriage rate. Results 256 men with non-obstructive azoospermia underwent 292 mTESE procedures. Of these, 90 men underwent a total of 99 mTESE procedures where only elongated spermatids were retrieved and ICSI later performed. One hundred-thirty eight ICSI cycles were performed using fresh or frozen elongated spermatids. Fertilization and blastulation rates were 35.3% and 19.3% overall. Clinical pregnancy and live birth rates were 4.3% and 2.9%, respectively. There were no differences between live birth outcomes with fresh and frozen elongated spermatids (p = 0.36). This relationship persisted after adjusting for male age at time of mTESE, female age at time of ICSI, and number of oocytes inseminated (fresh vs. frozen-thawed, OR=0.40 [0.03-5.33]). Conclusion A non-significant difference in reproductive outcomes between fresh and frozen-thawed elongated spermatids can facilitate scheduling of mTESE procedure before or concurrently with ovarian stimulation cycles without compromising patient outcomes. However, the overall very poor reproductive outcomes with elongated spermatids suggests that very thorough counselling of patients utilizing spermatids should be mandatory, and use of donor sperm should be strongly considered to improve chances of a live birth.