Physiological Intracytoplasmic Sperm Injection (PICSI)
PICSI – What is Physiological Intracytoplasmic Sperm Injection (PICSI)?
During Intracytoplasmic Sperm Injection (ICSI), sperm are selected based on their morphology and motility (i.e., their shape and movement). However, this doesn’t tell us about the sperm’s ability to fertilise an egg, nor whether it is likely to be successful. Physiological Intracytoplasmic Sperm Injection (PICSI) is a special test for sperm to help the specialists select and inject a single, healthy sperm directly into a mature egg.
PICSI – How can PICSI help us?
PICSI is a new technique for identifying healthy, functional sperm for injection into mature eggs, improving the chances of a successful fertilisation and reducing miscarriage risk.
PICSI is an excellent choice for couples where the male partner has documented issues with sperm volume, motility, morphology and/or functionality.
The potential improvement in fertility that PICSI offers depends on the woman’s age, diagnosis and the initial male semen analysis, and will be discussed with your specialist. Please be assured that your concerns will be discussed in detail with your specialist, prior to any treatment being initiated.
PICSI – Who is PICSI recommended for?
PICSI may be particularly useful for couples, when:
- There is a previous history of poor or low fertilisation,
- There is a history of repeated implantation failure,
- There is a previous history of poor embryo development ,
- The male partner has reduced sperm morphology and/or motility, or high sperm fragmentation,
- Previously frozen sperm is of low ‘quality’, and
- There is a high miscarriage rate.
PICSI is not available for patients using testicular sperm (i.e. where most sperm are not motile), or patients with ≤ 1 million motile sperm in final sample preparation.
PICSI – An overview of PICSI. What will happen?
During ICSI, motile sperm are selected for injection, based on their morphology and motility (i.e., how they are shaped and how they move). We know that using this simple visual approach may not necessarily tell us about the true health and functionality of the sperm.
The PICSI test is based on the innate ability of the sperm to bind to a natural substance called Hyaluronan (HA) – hydrogel. In the test dish, HA mimicks the coating of the mature eggs, and healthy sperm will attempt to bind to it – just as they would to an egg.
Sperm encounters HA in the mucus of the cervix, as well as in the coating of the egg. Penetration of the mucus and the egg are critical to successful fertilisation and subsequent embryo implantation in the uterus. PICSI simply takes advantage of this naturally occurring happening. A drop of prepared sperm is added to the special dish, which contains small dots of HA. The scientist can then select an HA-bound sperm for injection. The sperm that bind to HA are considered better quality, more mature sperm.
We know from years of research that sperm bound to HA are more likely to have less DNA damage and a normal chromosome complement. So, while there is usually no difference in the total number of eggs that are fertilised, there is generally better embryo development, and ongoing pregnancy rates, compared with standard ICSI.