Definition - What does Rescue ICSI mean?
Rescue ICSI refers to the process of performing intracytoplasmic sperm injection (ICSI) during a cycle of in vitro fertilization (IVF) after natural insemination, where sperm an eggs are allowed to fertilize naturally in a lab, fails to produce any fertilized eggs. This final attempt to fertilize eggs is rarely successful, so many clinicians do not even offer this option to their patients who have experienced complete fertilization failure.
FertilitySmarts explains Rescue ICSI
In a typical cycle of IVF, sperm and mature eggs are placed in a petri dish together in hopes that some of the sperm will fertilize some of the eggs. Unfortunately, fertilization does not always successfully occur in this setting. In fact, complete fertilization failure occurs in about 10-25% of cycles of IVF. This means that none of the eggs collected in that cycle were successfully fertilized. A number of factors may contribute to complete fertilization failure including, defective eggs, abnormal sperm, improper stimulation of the ovaries prior to egg retrieval, and environmental conditions.
Rescue ICSI was developed in attempt to overcome this barrier of fertilization failure. This process involves performing intracytoplasmic sperm injection (ICSI) on day 1 of a unfertilized mature egg. In other words, if none of the eggs in a cycle of IVF have successfully fertilized, a single sperm will be injected into one of the mature eggs.
The ability of rescue ICSI to produce successful fertilization and pregnancy is questionable. Reasons for its failure include in vitro aging of eggs and poor embryo quality. Some studies have found that this procedure is rarely successful, so many clinicians do not even offer this option to their patients. However, others believe that even with its questionable success rates, rescue ICSI should be attempted as a last effort to conceive after a failed cycle of IVF.