Assisted oocyte activation effects on the morphokinetic pattern of derived embryos

Area of Science:

• Reproductive Science
• Embryology
• In Vitro Fertilization

Background:

• Assisted oocyte activation (AOA) is an experimental technique used to improve fertilization rates in cases of IVF/ICSI failure.
• The downstream effects of AOA on embryo development are not fully understood.
• Investigating AOA's impact on preimplantation morphokinetics can provide insights into embryo quality and viability.

Purpose of the Study:

• To compare the preimplantation morphokinetic development of embryos resulting from ICSI with AOA versus standard ICSI.
• To evaluate potential differences in embryo developmental patterns between the two groups.

Main Methods:

• A retrospective cohort study analyzed 141 embryos from fresh oocyte donation cycles (2013-2017).
• Embryos were divided into an ICSI-AOA group (41 embryos) and a standard ICSI control group (100 embryos).
• Morphokinetic development was monitored using a time-lapse system.

Main Results:

• Embryos from both ICSI-AOA and ICSI groups exhibited similar development for most morphokinetic milestones.
• Significant differences were observed in the time of second polar body extrusion (tPB2) and the time to the second cell division (t3).

Conclusions:

• Ionomycin-mediated AOA does not appear to broadly affect the morphokinetic pattern of preimplantation embryo development.
• Observed alterations in tPB2 and t3 likely reflect the transient, non-physiologic increase in intracellular calcium induced by the ionophore.
• Further research is needed to fully elucidate the long-term implications of these specific developmental changes.