Assisted Reproductive Technique: ICSI
Intracytoplasmic Sperm Injection (ICSI) is an advanced micromanipulative technique in which a single sperm is injected into an oocyte (mature egg cell) retrieved through an in vitro fertilization (IVF) cycle.
After the retrieved oocytes are scored for maturity and incubated for 3-4 hours, those oocytes which are morphologically intact are candidates for ICSI. After sperm are obtained and selected, the ICSI procedure is done under a microscope using multiple micromanipulation techniques. With the sperm and oocytes in the Petri dish, a single motile sperm with normal morphology is first immobilized and then aspirated tail-first into the injection pipette. The sperm in the injection pipette is positioned at its very tip prior to injection. The micropipette is pierced through the cell membrane and into the inner part of the oocyte (cytoplasm). The sperm is then released into the oocyte. The needle is then withdrawn.
After 16 to 18 hours of incubation, the oocytes are examined for the presence of fertilization. Embryo transfer can be performed from 35 days after oocyte harvest. Depending on maternal age and the reproductive endocrinologist's preferences, generally from 1 to 3 of the morphologically best embryos are transferred to the uterus.