Analysis of Factors Affecting Fertilization and Pregnancy Rate in Intracytoplasmic Sperm Injection Using Ejaculated Sperm

Jun, J H; Lim, C K; Kim, J W; Byun, H K; Han, M H; Lee, H J; Choi, B C; Yoo, K J; Baik, E C; Koong, M K; Son, I P; Kang, I S; Jun, J Y

Abstract

Intracytoplasmic sperm injection (ICSI) has been reported as the most successful technique to obtain high fertilization and pregnancy rate in infertile couples who could not be helped by traditional in vitro fertilization or previously described techniques of assisted fertilization. We performed retrospective analysis, in relation to the number of retrieved (NRO) and injected oocytes (NIO), sperm parameters, maturation rate of retrieved oocytes (MRO), fertilization rate after ICSI (FRI) and age of patient (AGP) in 975 ICSI cycles using ejaculated sperm during 1994~1996. The purpose of this study was to determine the important factors affecting fertilization and ongoing pregnancy rate in the ICSI cycles using ejaculated sperm. A total of 8,809 injected oocytes, 6,138 (69.7%) oocytes were normally fertilized and 213 (22.8%) ongoing pregnancies were achieved in 933 cycles of embryo transfer. The fertilization rates were significantly different in relation to NRO (from 67.3% to 75.0%), NIO (from 68.5% to 73.9%), sperm parameters (from 64.4% to 73.0%), MRO (from 64.6% to 73.9%)and AGP (from 67.8% to 74.4%), respectively. The ongoing pregnancy rates were significantly different in relation to NRO (from 10.0% to 26.6%), NIO (from 10.4% to 27.9%), FRI (from 18.5% to 30.6%) and AGP (from 6.7% to 25.4%), respectively. From these results, it can be concluded that ICSI using ejaculated sperm can provide high normal fertilization rates (above 64%) in all groups analyzed and NRO, NIO, FRI and AGP are important factors determining a successful ongoing pregnancy.