Comparative effectiveness of physiological intracytoplasmic sperm injection and intracytoplasmic sperm injection in couples affected by abnormal sperm morphology

Objective: This study compared outcomes after physiological intracytoplasmic sperm injection (PICSI) versus conventional intracytoplasmic sperm injection (ICSI) in couples affected by abnormal sperm morphology.Methods: This retrospective cohort study included 246 couples in whom the male partner had abnormal sperm morphology, defined as normal morphology <4% according to World Health Organization 2021 criteria, and who underwent assisted reproductive treatment at the in vitro fertilization and Tissue Engineering Center, Hanoi Medical University Hospital, from January 2022 to January 2024. Couples underwent either PICSI or conventional ICSI according to routine clinical practice. To reduce confounding, 1:1 matching based on female age, anti-Müllerian hormone level, and antral follicle count was performed. Embryological and clinical outcomes were compared between groups. Clinical outcomes were assessed only in first frozen embryo transfer cycles using day-5 blastocysts.Results: No significant differences were observed between the PICSI and ICSI groups in embryological outcomes, including the number of metaphase II oocytes, fertilization rate, day-5 blastocyst formation rate, and high-quality blastocyst rate. Clinical outcomes were also comparable, including the rates of positive serum beta-human chorionic gonadotropin, clinical pregnancy, implantation, ongoing pregnancy, pregnancy with multiple gestational sacs, and live birth. Subgroup analyses stratified by female and male age likewise showed no significant differences in outcomes.Conclusion: In this real-world Vietnamese cohort of couples affected by abnormal sperm morphology, PICSI demonstrated no significant advantage over conventional ICSI. These findings support individualized selection of sperm injection techniques rather than routine PICSI use. Future prospective studies incorporating sperm DNA fragmentation testing and sibling-oocyte designs are warranted.