Six-time Olympic gold medallist Allyson Felix gave birth to a baby girl via emergency C-section last month and despite the premature birth, both mother and child were "doing fine," US Track and Field said on Thursday.
Medical complications required the baby, named Camryn, to be born at 32 weeks and she will need additional time in the neonatal intensive care unit before she can come home.
"I'm trying to be open to what God has in store for me and my family," Felix wrote in a message posted to the team's website.
"I still feel nervous and vulnerable. But I also feel brave and excited. Every day I sit with my daughter in the NICU and watch her fight. Every day she gets stronger and more beautiful."
News of the birth came as a surprise to her fans since the Los Angeles native had not previously said she was pregnant.
The 33-year-old sprinter, the most decorated American woman in track and field history, was set to announce her pregnancy before the emergency C-section on Nov 28 derailed those plans.
Felix said she planned to compete at the Tokyo Olympics in 2020 and would run with a new sense of purpose.
"I'm not just running to win the most medals anymore," she said in a first-person article published by ESPN on Thursday.
"If I come back and I'm just not the same, if I can't make a fifth Olympic team, I'm gonna know that I fought, that I was determined, and that I gave it my absolute all.
"And if it doesn't end up the way I imagined in my head, it'll be OK. I just have to go for it, because that's just simply who we are now."