25 Mar PICSI or MACS – Which Is Better?
PICSI and MACS are two techniques used by fertility clinics to obtain the best quality sperm. Most patients won’t need either. But for couples where sperm quality is a concern, PICSI, MACS, or both, could give ICSI a run for its money and improve IVF outcomes.
Poor sperm quality isn’t always apparent. ICSI selects the best-looking sperm, relying to some degree on the visual skill of the andrologist or embryologist. But good motility and morphology don’t guarantee sperm maturity. They could still be immature. which often means damaged DNA. ICSI preparation on its own can’t spot this.
Step forward PICSI – short for preselected intracytoplasmic sperm injection. PICSI can identify better quality sperm by placing sperm samples in a petri dish containing a substance called hyaluronic acid. The natural version of this is found on the surface of human eggs and elsewhere in the body, including the endometrial lining (see embryo glue – another hyaluronan imitator). The top-quality mature sperm bind to the hyaluronan better than immature sperm, as they might in natural conception. This gives labs better visual information on the sperm’s quality, though DNA damage can still not be seen. The identified mature sperm are then injected into the mature eggs using ICSI.
The best summary of PICSI? It’s an advanced form of ICSI. And who might benefit? Couples with a known male-factor issue (e.g. high DNA fragmentation), with recurring pregnancy loss or poor embryo development/fertilisation in previous IVF cycles.
Current research is inconclusive. PICSI might reduce pregnancy loss for certain couples but, in a more recent study, live birth rates appear to be no better than ICSI cycles. It’s another add-on that needs more randomised trials. That doesn’t mean it should be discounted as an option for certain couples.
MACS (magnetically activated cell sorting) takes a different approach. Think of it as a medical border crossing for sperm, with a magnetic turnstile separating the wheat from the chaff. Like PICSI, MACS is a sperm-selection method. The kit positions sperm adjacent to a magnetic column. The better quality sperm (e.g. with lower DNA fragmentation or development issues) pass through the column. Those that get through can be used in ICSI and injected into the mature eggs, hopefully improving the outcome for that pregnancy. The poorer quality, apoptotic (dying) sperm, which may otherwise have contributed to a pregnancy failure, are left behind and discarded.
Which is best – PICSI or MACS? Some patients are recommended both, but the pros and cons are technical. PICSI involves more manipulation of the individual sperm cells, the culture may damage the performance of some cells and you need good motile sperm. MACS is more mechanised: the entire selection is done in one go. As it’s less invasive, less can go wrong. But it’s often more expensive than PICSI.
MACS and PICSI are both interesting additions to a fertility clinic’s range of cell-selection options. No add-on comes with certainties. But the best person to advise on their use is your fertility doctor. It’s worth having the conversation.