Artificial oocyte activation in severe teratozoospermia undergoing intracytoplasmic sperm injection.

OBJECTIVE: To evaluate efficiency of ionomycin on fertilization and cleavage rates, embryo development, and pregnancy rate after intracytoplasmic sperm injection (ICSI) in teratozoospermic patients.

DESIGN: Laboratory study.

SETTING: Isfahan fertility and infertility Center, and Royan institute, Tehran, Iran.

PATIENT(S): Eighty-seven couples with male factor etiology (severe teratozoospermia) undergoing ICSI.

INTERVENTION(S): Ionomycin for artificial oocyte activation.

MAIN OUTCOME MEASURE(S): After oocyte collection, the oocytes were randomly divided into two groups: control and artificial oocyte activation (AOA). The injected oocytes in the control group were cultured in G1. The remaining oocytes were chemically activated by exposure to 10 muM ionomycin for 10 minutes. Around 16 to 18 hours after ICSI, fertilization was assessed by the presence of pronuclei. The percentage of cleavage and high-quality embryos were calculated 48 and 72 hours after ICSI. Clinical pregnancy also was determined based on ultrasound observation of a fetal heart beat.

RESULT(S): There are significant differences in the mean of fertilization and cleavage rates 72 hours after ICSI between AOA and control groups. In patients who had no fertilization in the control group and all the embryos for transfer derived from the AOA group, two pregnancies were recorded. In the patients who had poor fertilization rate (1%-33%) in the control group (14.30%), there was a significant increase in mean fertilization rate (58.31%) because of AOA. The results of the present study also reveal that the samples had motile sperm, whereas in the chemically activated group this difference was not significant. CONCLUSION (S): It can be concluded that in cases with severe teratozoospermia AOA may improve fertilization and cleavage rates, which in turn, affect the implantation and pregnancy rate.