Successful pregnancy and delivery after ICSI with artificial oocyte activation by calcium ionophore in in-vitro matured oocytes: a case report

The achievement of a successful pregnancy and delivery after oocyte activation with calcium ionophore is reported in a couple having low fertilization rates after intracytoplasmic sperm injection (ICSI) of in-vitro matured oocytes. A couple, in which the wife had polycystic ovary syndrome and the husband had moderate oligoteratozoospermia, showed a low fertilization rate in a previous in-vitro maturation cycle (2/11 [18.2%]). The most likely cause of complete fertilization failure or low fertilization rates is failure of oocyte activation. Therefore, artificial oocyte activation by calcium ionophore was combined with ICSI to achieve viable fertilized oocytes. Oocytes were stimulated with calcium ionophore for 30 min after ICSI. The fertilization rate of oocytes activated with calcium ionophore (13/15 [86.7%] and 7/9 [77.8%]) was higher than that of the non-activated oocytes. In the latest cycle, three embryos derived from the activated oocytes were transferred into the uterus on day 3. Subsequently, two gestational sacs were identified on ultrasound. The patient delivered dizygotic twins (girl 2260 g and boy 2760 g) at 35 weeks and 6 days gestation by caesarean section. This result suggests that calcium ionophore could be useful for oocyte fertilization in couples with low fertilization rates after ICSI of in-vitro matured oocytes.