A discovery by a team of researchers at McGill University could eventually enable women undergoing in vitro fertilization (IVF) avoid painful hormone injections while increasing the procedure’s success rate. The researchers are focusing on creating a light-activated microneedle patch, which would replace daily injections before an egg retrieval for a woman hoping to get pregnant via IVF. As it stands, the success rate of in vitro fertilization is 30 per cent, largely due to specificities surrounding the injections. “One of the problems with in vitro fertilization is that it often doesn’t work [...] because it’s difficult to remember to inject yourself every day at the same time, and if you make mistakes in the timing of the injection, it can compromise the treatment,” explained Marta Cerruti, professor of materials engineering at McGill University and lead author of the study. If approved, the researchers’ light-activated patch could be programmed to inject medication at a specific time. That means a woman receiving hormone injections could wear the patch for a week, and the injections would be administered automatically at the same time each day. The patch is composed of hydrogel microneedles filled with nanoparticles, which, when stimulated by infrared light, release leuprolide, a key hormone for in vitro fertilization. Benefits for other diseases Light-triggered microneedle patches are not a new technology, but this research is the first to explore ways to release a substance that isn’t foreign to the body. “In order to release a drug with light, we have to break the bonds in the matrix containing the drug. The only light we can use to break these bonds is ultraviolet light,” said Cerruti, noting that ultraviolet (UV) light is carcinogenic and should be avoided when possible. “What we did was put very special nanoparticles in the patch that are capable of transforming infrared light into ultraviolet light,” she said, adding that the goal was to use nanoparticles without releasing them into the body. “With this idea of microneedle technology, we put them in a matrix with microneedles that prevent the nanoparticles from passing into the body. Only the drug is released by the particles with infrared light,” she said. For now, the tests have been conducted on rats, and before moving on to a human clinical trial, there must be further testing on larger animals. That means it could be years before Health Canada evaluates the device and decides whether or not to approve it. All the same, the researchers point out that the technology could be used to aid people with other health conditions, including diabetes or multiple sclerosis. Cerruti’s study was published in the scientific journal Small, with contributions by Vivienne Tam, Rusvir Trana, Alfonso Nieto-Arguello, Ore-Oluwa Olasubulumi, Samuel Babity, Artiom Skripka, Fiorenzo Vetrone and Davide Brambilla. The Canadian Press’s health coverage is supported by a partnership with the Canadian Medical Association. The Canadian Press is solely responsible for this journalistic content. This report by The Canadian Press was first published in French on Jan. 8, 2026.
