In cases of poor embryo development in previous ICSI cycles or when there is high sperm DNA fragmentation, we may opt to carry out a version of ICSI called PICSI. Basically, by isolating the better-quality sperm before we inject it, the resulting embryo might be of better quality too.
To do this, we mimic the natural way a sperm attaches to the egg; where it binds to a molecule on the egg surface called hyaluronan. In PICSI, the sperm are placed in a dish with samples of a special ‘hyaluronan hydrogel’ and the most mature and competent sperm (those which bind to the hyalorunan) are then isolated and used for ICSI.
The rest of the process is the same as for standard IVF and ICSI.
Currently, this technique is categorised as “red” on the HFEA’s traffic light rating system in view of insufficient evidence showing improvement in pregnancy rates and is therefore not recommended for routine use. However, PICSI is a non-invasive procedure performed on the semen sample as an additional step in the ICSI process. Compared to ICSI, there are no known additional risks associated with PICSI and as such there are no significant additional risks to the woman or embryo.