Objective: To establish an intracytoplasmic sperm injection treatment program for couples with male infertility and to determine those factors important for success.
Design: A retrospective analysis of 171 consecutive cycles of intracytoplasmic sperm injection concerning 145 infertile couples.
Setting: Infertility clinic in a private hospital associated with a university hospital.
Patients: Couples with infertility in the male partner whose sperm parameters were unacceptable for conventional IVF or in whom fertilization by conventional IVF failed repeatedly.
Interventions: One hundred seventy-one transvaginal oocyte retrievals were completed after superovulation with GnRH agonist and gonadotropins.
Main outcome measures: The parameters evaluated included fertilization, cleavage, implantation, pregnancy, and spontaneous abortion in relation to patient indications and improved procedures.
Results: After intracytoplasmic sperm injection, normal fertilization occurred in 45% of the oocytes (n = 1,499). Of 171 treatment cycles, 93% of the couples had fertilization and 86% had ET. Thirty-six pregnancies were achieved. During the period studied, the mean fertilization rate increased from 21.3% during the first 17 weeks to 67.8% during the last 13 weeks, and the pregnancy rate (PR) per started cycle increased from 12.8% to 31.3%.
Conclusions: Technical factors critical for achieving high rates of fertilization and pregnancy were the use of standardized intracytoplasmic sperm injection pipettes, the immobilization of sperm before injection, and the aspiration of a minimal amount of ooplasm before reinjection with the sperm. Intracytoplasmic sperm injection appears to be superior to other micromanipulation methods for alleviating male infertility.