Artificial oocyte activation with Ca2+ ionophore improves reproductive outcomes in patients with fertilization failure and poor embryo development in previous ICSI cycles

Research question

Does artificial oocyte activation (AOA) by a calcium ionophore (ionomycin) improve the previous fertilization failure or poor embryo development of intracytoplasmic sperm injection (ICSI) account for male factor infertility or other infertility causes?

Design

This retrospective study involved 114 patients receiving ICSI-AOA in Shanghai First Maternity and Infant Hospital with previous ICSI fertilization failure or poor embryo development. The previous ICSI cycles of the same patients without AOA served as the control group. The fertilization rates, cleavage rates, transferable embryo rates and blastocyst formation rates of the two groups were compared. Additionally, the clinical pregnancy, implantation rate and live birth rates were also compared to assess the efficiency and safety of AOA. Furthermore, two subgroup analyses were performed in this study based on the cause of infertility and the reason for AOA. The fertilization rate, embryonic development potential and clinical outcome were compared among groups.

Results

Among 114 ICSI-AOA cycles, the fertilization rate, top-quality embryo rate, implantation rate, clinical pregnancy per patient and live birth rate per patient were improved significantly compared with previous ICSI cycles (p<0.05 to P< 0.001), and the miscarriage rate in the AOA group was significantly lower than that of the control group (p<0.001). In the AOA subgroups based on the cause of infertility, the fertilization rates of each subgroup were significantly improved compared with previous control cycles except for the mixed factor infertility subgroup (p<0.05 to p<0.001). In the AOA subgroups based on the reason for AOA, the fertilization rates of each subgroup were significantly increased compared with those in their previous ICSI cycle without AOA (p<0.001); however, there was no significant difference in the top-quality embryo rate. No significant improvement was found in the implantation rates and the clinical pregnancy rate in each subgroup except for the poor embryo development subgroup. In the 114 AOA cycles, 35 healthy infants (21 singletons and 7 twins) were delivered without major congenital birth defects or malformations.

Conclusion

This study showed that AOA with the calcium ionophore ionomycin can improve the reproductive outcomes of patients with previous fertilization failure and poor embryo development after ICSI.

Assisted oocyte activation with calcium ionophore 44 hours after intracytoplasmic sperm injection resulting in successful pregnancy

Assisted Oocyte Activation (AOA) with Calcium Ionophore, is possible to manually activate the oocytes and cure globozoospermia, thus leading to successful pregnancy in 1 h after ICSI. But in this case, we report a case that 44 h after ICSI, the arrest zygotes assisted oocyte activation with calcium ionophore, obtained clinical pregnancy and live birth. Accordingly, AOA may provide us with an immediate treatment for embryonic arrest in the future.

Comparison of Human Oocyte Activation Between Round-Headed Sperm Injection Followed by Calcium Ionophore Treatment and Normal Sperm Injection in a Patient With Globozoospermia

Fertilization failure is common in patients with round-headed sperm, a form of globozoospermia. Artificial oocyte activation is able to assist oocyte fertilization after sperm injection in these patients. Comparisons between oocyte fertilization with or without calcium ionophore have been reported in patients with round-headed sperm. However, no comparison has been reported between round-headed sperm injection followed by calcium ionophone activation and normal sperm injection. In this case report, half of oocytes from a patient were injected with her partner's round-headed sperm followed by calcium ionophore activation, and the other half of oocytes were injected with a donor sperm without calcium ionophore activation. The injected oocytes were cultured to examine fertilization, embryo development, and embryonic aneuploidies in the resulting blastocysts. The fertilization rate was lower in round-headed sperm injected oocytes (3/6) than that in donor sperm injected oocytes (5/6), but rates of blastocyst and aneuploidies were similar in the resulting embryos between the two groups. A euploid blastocyst resulted from round-headed sperm injection was transferred, and a healthy baby was delivered. These results indicate that calcium ionophore treatment can assist oocyte activation in patients with round-headed sperm, but its efficiency to activate oocytes is lower than that induced by a normal sperm injection. However, embryo development and chromosome integrity may not be affected by calcium ionophore treatment.

Pregnancy and neonatal outcomes of artificial oocyte activation in patients undergoing frozen-thawed embryo transfer: a 6-year population-based retrospective study

PURPOSE

To evaluate the impact of artificial oocyte activation (AOA) in pregnancy and neonatal outcomes in infertile patients undergoing cryopreserved embryo transfer.

METHOD

This retrospective study included 5686 patients' transferred embryos from routine intracytoplasmic sperm injection (ICSI) and 194 patients' transferred embryos from ICSI combined with AOA (ICSI-AOA) from January 2011 to December 2016. Pregnancy and neonatal outcomes of couples undergoing routine ICSI or ICSI-AOA were analyzed before and after propensity score matching. Artificial oocyte activation was performed with ionomycin.

RESULTS

The pregnancy outcomes showed no significant difference in the rates of biochemical pregnancy, clinical pregnancy, implantation, miscarriage, ectopic pregnancy, multiple pregnancy, and live births between the routine ICSI and ICSI-AOA groups before and after propensity score matching, respectively. The assessment of neonatal outcomes showed no statistically significant differences in the birth defect rate, birth weight, gestational age, preterm birth rate, early-neonatal death rate, and fetal sex ratio between the two groups, and similar results were also observed in the two matched cohorts.

CONCLUSION

Artificial oocyte activation with ionomycin does not adversely affect pregnancy and neonatal outcomes in patients undergoing frozen-thawed embryo transfer, which is beneficial to clinicians counseling patients on the risks of artificial oocyte activation.

[Application of calcium ionophore A23187 in ICSI for globozoospermia: A report of 2 cases and review of the literature]

OBJECTIVE

To investigate the pathogenesis of globozoospermia, fertilization ability of round-headed sperm, and the application value of assisted oocyte activation in intracytoplasmic sperm injection (ICSI) for the wives of glohozoospermia men.

METHODS

We collected oocytes from the wives of 2 globozoospermia patients and randomly divided them into two groups after ICSI to receive calcium ionophore A23187-activation and conventional treatment, respectively. We reviewed the relevant literature published at home and abroad, and discussed the etiology of globozoospermia, fertilization ability of round-headed sperm, and treatment options for this disease.

RESULTS

Quality embryos were obtained in the A23187-activation group while no fertilized oocytes, oocyte cleavage, quality embryos, or blastular formation were found in the conventional treatment group. Both women achieved pregnancy and gave birth to healthy neonates after transfer of the quality embryos from the A23187-activation group.

CONCLUSION

Calcium ionophore A23187 can be applied to ICSI for the wives of globozoospermia men and bring about desirable clinical outcomes. Meanwhile, attention should be paid to its safety.