Objective: To evaluate the significance of intracytoplasmic sperm injection in severe male factor 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.