Application of a ready-to-use calcium ionophore increases rates of fertilization and pregnancy in severe male factor infertility

Abstract

Objective: To analyze whether a ready-to-use calcium ionophore improves outcomes, from fertilization to live birth, in patients with severe male factor infertility.

Design: Artificial oocyte activation offered to applicable patients over a 20-month period.

Setting: Specialized in vitro fertilization (IVF) centers in Austria and Germany.

Patient(s): Twenty-nine azoospermic and 37 cryptozoospermic men.

Intervention(s): Mature oocytes treated with a ready-to-use Ca(2+)-ionophore (GM508 Cult-Active) immediately after intracytoplasmic sperm injection (ICSI).

Main outcome measure(s): Rates of fertilization, implantation, clinical pregnancy, and live birth.

Result(s): Patients had had 88 previous cycles without artificial activation that resulted in a fertilization rate of 34.7%, 79 transfers (89.8%), and 5 pregnancies, which all spontaneously aborted except one. After artificial oocyte activation, the fertilization rate was 56.9%. In terms of fertilization rate, both azoospermic (64.4%) and cryptozoospermic (48.4%) men statistically significantly benefited from use of the ionophore. In 73 transfer cycles, positive β-human chorionic gonadotropin levels were observed in 34 cases (46.6%) and 29 cycles (39.7%) that ended with a clinical pregnancy. The corresponding implantation rate was 33.3%. Four spontaneous abortions occurred (11.8%), and 32 healthy children were born.

Conclusion(s): This is the first prospective multicenter study on artificial oocyte activation in severe male factor infertility. Present data indicate that a ready-to-use calcium ionophore can yield high fertilization and pregnancy rates for this particular subgroup. In addition to fertilization failure after ICSI, severe male factor infertility is an additional area for application of artificial oocyte activation.