Northwestern researchers discovered a “firework” that sparks when a human egg is injected with sperm enzyme and acts as an indicator to the egg’s fertility.

The study, published in Scientific Reports, detailed a zinc spark that erupts when an egg is fertilized, with the size of the explosion directly measuring the egg’s fertility, according to a University news release. The findings could help doctors identify the best eggs for in vitro fertilization, the release said.

“This means if you can look at the zinc spark at the time of fertilization, you will know immediately which eggs are the good ones to transfer in in vitro fertilization,” Teresa Woodruff, a Feinberg professor and one of the study’s authors, said in the release. “It’s a way of sorting egg quality in a way we’ve never been able to assess before.”

Scientists injected the egg with sperm enzyme, triggering a calcium increase in the egg that leads to a release of zinc. The zinc binds to small molecule probes, giving off a flash of light that resembles a “firework.”

The eggs were not fertilized with actual sperm in accordance with restrictions under federal law.

“This is an important discovery because it may give us a non-invasive and easily visible way to assess the health of an egg and eventually an embryo before implantation,” Dr. Eve Feinberg, co-author of the study, said in the release. “If we have the ability up front to see what is a good egg and what’s not, it will help us know which embryo to transfer, avoid a lot of heartache, and achieve pregnancy much more quickly.”

Email: [email protected]
Twitter: @kellipnguyen