A baby that was born with the DNA of three people in New York’s New Hope Fertility Center is healthy and has grown to be five months old, doctors at the facility said. This is the first time a procedure called “mitochondrial transfer” has been successfully carried out, though other scientists have helped produce babies with the DNA of three people in the past, as well. The older procedure is now banned because of complications that arose in children born that way.

The baby at the New Hope clinic was born on April 6. He has the DNA of both his parents and a small amount of genetic material from a donor. This helped prevent him from picking up a rare genetic neurological condition his mother carries, doctors said. Mitochondria, a component of the cell, in women can sometimes carry genetic defects to which their unborn children are susceptible.

The couple had had four miscarriages and lost two children before they were able to get through to the New York clinic. While some have questioned the ethics of the controversial and tightly regulated procedure, doctor John Zang, who led the team said, “To save lives is the ethical thing to do.” Scientists hope that the successful birth will fuel more research in the area and convince dissidents of its efficacy.