Is there a relation between the time to ICSI and the reproductive outcomes?

Area of Science:

• Reproductive Science
• Embryology
• In Vitro Fertilization

Background:

• Oocyte maturation, both cytoplasmic and nuclear, is crucial for successful embryonic development.
• Excessive in vitro culture of mature oocytes can negatively impact their quality and developmental potential.

Purpose of the Study:

• To investigate the impact of time intervals between oocyte pickup (OPU) and intracytoplasmic sperm injection (ICSI) on reproductive outcomes.
• To determine if delays in ICSI affect fertilization, pregnancy, and live birth rates in fresh embryo transfers.

Main Methods:

• A retrospective cohort study of 1468 ICSI cycles using fresh embryo transfers.
• Exact culture times (OPU-denudation, denudation-ICSI, OPU-ICSI) were recorded.
• Statistical analyses, including regression modeling, were used to assess the effect of time on various reproductive outcomes, adjusting for confounding factors.

Main Results:

• Each 1-hour increase in OPU-ICSI time was associated with a 7.3% decrease in biochemical pregnancy and a 7.7% decrease in clinical pregnancy.
• Increased OPU-ICSI time positively correlated with fertilization rates.
• No significant effect of time was observed on ongoing pregnancy or live birth rates.

Conclusions:

• In vitro aging of mature oocytes significantly impacts pregnancy chances.
• Limiting the incubation time of mature oocytes before ICSI may enhance reproductive success in fresh embryo transfer cycles.
• Further research is needed to fully understand the effect on live birth rates.