Japanese society of Ova Research

Abstract

Vol.32 No.3

Abstarct Full Text of PDF
Original
Effect of artificial oocyte activation by calcium ionophore on one-day-old unfertilized oocytes after ICSI
JMOR, 32(3) 115-120, 2015
DOI: 10.1274/jmor.32.115
1Ochi Yume Clinic Nagoya, Aichi 460-0002, Japan
2Prefectural University of Hiroshima, Hiroshima 727-0023, Japan

At our clinic, a successfully fertilized human oocyte is defined as one with two polar bodies and two pronuclei (PN) 18 h after ICSI, but when some oocytes do not form PN. Recently, a successful pregnancy and live birth following artificial oocyte activation (AOA; using Ca2+ ionophore) of ICSI-treated one-day-old unfertilized oocytes was reported. In this study, we performed AOA on PN-lacking unfertilized oocytes, 18 h after ICSI (defined as Day 1-AOA, since ICSI=Day 0). The abilities of these oocytes to form PN and develop were compared with those of oocytes fertilized by ICSI (defined as No-AOA). Piezo-ICSI was performed on 168 oocytes, 50 of which failed to fertilize (0PN) but were subsequently artificially activated. 2PN formation rate was significantly lower in Day 1-AOA, and the rates of 1PN and ≥4PN were significantly higher than in No-AOA. In Day 1-AOA, 8 oocytes formed 2PN, 6 zygotes underwent cleavage and 2 of them developed to the morula stage, but none formed blastocysts. The rates of cleavage, morula, and blastocyst formation were significantly lower in Day 1-AOA than in No-AOA. These results suggest that the AOA protocol has room for improvement in the activation of unfertilized oocytes 18 h after ICSI.

Google Scholar