Successful pregnancy after ICSI with strontium oocyte activation in low rates of fertilization

Abstract

Fertilization failure (complete fertilization failure or low fertilization rates) after intracytoplasmic sperm injection (ICSI) can occur in rare cases. In the majority of these cases, the unfertilized oocytes are inactivated. Assisted oocyte activation was applied as a treatment option for a case of low fertilization rate as a clinical trial. A patient with a low fertilization rate (ranging from 0% to 33.3%; mean = 17.0%) after eight previous ICSI cycles at another hospital, was diagnosed with fertilization failure. The most likely cause of fertilization failure was failure of oocyte activation. Therefore, artificial oocyte activation by strontium treatment was combined with ICSI to achieve viable fertilized oocytes. Oocytes were stimulated with strontium (10 mM SrCl(2), 60 min) approximately 30 min after ICSl. Six injected oocytes were stimulated and all were then successfully fertilized. Two blastocysts were transferred into the uterus, resulting in a pregnancy and birth. A second pregnancy was achieved following implantation of two cryopreserved embryos (one blastocyst and one morula). In conclusion, strontium treatment was found to be an effective method for artificial oocyte activation in a case with a low fertilization rate after ICSI.

Live birth after SrCl2 oocyte activation in previous repeated failed or low fertilization rates after ICSI of frozen-thawed testicular spermatozoa: case report

“…Recently, several reports have demonstrated the efficacy of SrCl 2 after ICSI in couples who experienced complete fertilization failure or low fertilization rates in previous cycles of ICSI [17][18][19]. These results show that SrCl 2 treatment is useful for activating human oocytes that frequently fail to fertilize in ICSI.…”

“…When the oocytes were activated using electroporation [4,5], calcium ionophore [6][7][8][9][10][11][12][13][14], or calcium ionophore and puromycin [15,16], followed by ICSI in women whose oocytes failed to fertilize in previous IVF cycles, some of them could form pronuclei. Recently, several studies were reported that strontium chloride (SrCl 2 ) treatment on infertile patients resulted in successful pregnancies and deliveries [17][18][19]. Especially, SrCl 2 is excellent for improving fertilization, embryo quality, and pregnancy in women who showed complete fertilization failure or low fertilization rates.…”

Pregnancy outcome after intracytoplasmic sperm injection with strontium oocyte activation in a globozoospermic patient

“…Four case reports have been published demonstrating improved fertilisation rates and embryo quality following strontium was used for AOA in humans with low or no fertility, and successful pregnancies and live births have been achieved. [5][6][7] Our study is the first reported case of successful pregnancy and live births after strontium was used for AOA with globozoospermic sperm. However, the fertilisation rate was not improved after strontium treatment, even though it seemed to improve the quality of the embryos.…”

“…3,4 Strontium treatment, which is proven to induce calcium oscillations in mice, was found to be an effective method for AOA in cases of low or absent fertilisation after ICSI. [5][6][7] Whether strontium is effective at improving fertilisation by globozoospermic sperm has not been reported. We report a successful case of a twin pregnancy resulting in live births following ICSI and strontium oocyte activation with round-headed sperm.…”

“…The efficiency of SrCl 2 for oocyte activation varies depending on the species. 5 It is most effective in mice, but in human oocytes, calcium oscillation has not been observed, which is the key to oocyte activation. Four case reports have been published demonstrating improved fertilisation rates and embryo quality following strontium was used for AOA in humans with low or no fertility, and successful pregnancies and live births have been achieved.…”