While this is a first for the US, it's not the first ever. A group in Sweden achieved the very first post-transplant births, a total of eight, and the birth that just took place at Baylor is the first to replicate the Swedish team's success.

The birth was a big moment for everyone involved in the trial. "We do transplants all day long," Giuliano Testa, head of the clinical trial, told Time. "This is not the same thing. I totally underestimated what this type of transplant does for these women. What I've learned emotionally, I do not have the words to describe." Gregory McKenna, a transplant surgeon at the hospital said, "Outside my own children, this is the most excited I've ever been about any baby being born. I just started to cry."

Once a uterus is transplanted, the recipient must wait to achieve menstruation, which if the transplant is successful, usually occurs around four weeks later. Then, to get pregnant, they must go through in vitro fertilization since their uterus isn't attached to their ovaries.

The Baylor team says that many more uterine transplants will need to be done before this can become an approved treatment, but these initial successes are promising. "For the girl who is getting the [infertility] diagnosis now, it's not hopeless," Kristin Wallis, a uterine transplant nurse at Baylor told Time. "There's hope."