ASSISTED FERTILIZATION WITH INTRACYTOPLASMIC SPERM INJECTION

Objective: To evaluate the significance of intracytoplasmic sperm injection in severe male tor infertility and previous failed fertilization. Design: Prospective observational study. Setting: Private infertility clinic, London. Subjects: Sixty-nine patients with a long-standing history of infertility of which 48 had previous failed fertilization, 15 had <1 million progressive motile sperm per ejaculate, and the remaining 6 had obstructive azoospermia. Intervention: Assisted fertilization with primary intracytoplasmic sperm injection was carried out in 69 IVF. Outcome: Normal (two pronuclei [2PN]) fertilization and pregnancy rates. Results: A total of 967 oocytes were collected and 785 were subsequently microinjected. Normal fertilization (2PN) occurred in 410 oocytes (52%) and 90.5% of those cleaved. Sixty-four patients underwent ET, with a total of 181 embryos transferred. Twenty-five patients conceived with a pregnancy rate of 39% per transfer. The implantation rate was 16% and the total pregnancy loss rate 24%. Failed fertilization after intracytoplasmic sperm injection occurred in four cases. Conclusions: Intracytoplasmic sperm injection is increasingly becoming the treatment of choice in infertile couples where assisted fertilization is indicated. The high fertilization and pregnancy rates observed with this technique, together with a low risk of abnormalities, has revolutionized treatment of male factor infertility.