Percentage of motile spermatozoa at 22 hours after swim-up procedure: An indicator for intracytoplasmic sperm injection?

• Published in: Clinical and experimental reproductive medicine Vol. 43; no. 3; pp. 157 - 163
• Main Authors: Inoue, Taketo, Yonezawa, Yukiko, Sugimoto, Hironobu, Uemura, Mikiko, Ono, Yuri, Kishi, Junji, Emi, Nobuyuki, Ono, Yoshiyuki
• Format: Journal Article
• Language: Korean
• Published: 2016
• Subjects: Fertilization in vitro; Insemination; Spermatozoa; Sperm injections, intracytoplasmic
• ISSN: 2233-8233; 2233-8241

Objective: The decision to use in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), or split insemination (IVF-ICSI) in the first cycle is based on the number of motile sperm. Hence, total fertilization failure (TFF) often occurs during IVF cycles, despite normozoospermia. To investigate whether the cumulative motile swim-up spermatozoa percentage at 22 hours post-insemination (MSPPI) is an indicator for ICSI, we analyzed TFF, fertilization, blastocyst development, chemical pregnancy, clinical pregnancy, and live birth rates. Methods: This prospective study was performed using data obtained from 260 IVF cycles. At 22 hours after insemination, the remaining swim-up spermatozoa were observed and divided into six groups according to MSPPI (<10%, 10% to <30%, 30% to <50%, 50% to <70%, 70% to <90%, and 90% to 100%). Results: Regardless of the ejaculated motile sperm concentration ($0.6-280{\times}10^6/mL$ motile spermatozoa), the incidence of TFF significantly increased when MSPPI was <10%, and the fertilization rate significantly decreased when MSPPI was <30%. We found that cumulative MSPPI correlated with the cumulative fertilization rate (Spearman correlation, 0.508, p<0.001). Regarding embryo development, we observed no significant differences in the rates of blastocyst development, chemical pregnancy, clinical pregnancy, or live birth among all groups. Conclusion: Our findings suggest that MSPPI is a viable indicator for split IVF-ICSI and ICSI. Taken together, by employing the MSPPI test in advance before IVF, ICSI, or split IVF-ICSI cycles, unnecessary split IVF-ICSI and ICSI may be avoided.