CHICAGO (CBS) — Amber Miller was expecting her child at any moment, but that didn’t stop her from finishing Sunday’s Chicago Marathon.

And, about seven hours later, she gave birth to a baby girl.

Miller, 27, who had been training throughout her pregnancy, said she got the OK from her doctors to run half the marathon.

“I went into it not planning on finishing,” Miller told CBS 2’s Mai Martinez as she held her newborn, June. “I was fully expecting just to run a few miles, and then skip maybe the second half and run the last mile across the finish line. But I was feeling good.”

LISTEN: WBBM Newsradio’s Steve Miller Reports

She drew stares from spectators, but some of them yelled warm wishes, such as “Go, pregnant lady!” She alternated running and walking the route, finishing in six hours, 25 minutes.

The contractions started not long after. After dinner, she and her husband determined she was in labor. The couple called Central DuPage Hospital and headed in.

“I kind of said ‘I just got finished running, or I ran this morning.’ I didn’t give all the details,” Amber Miller said. “Finally, my husband, he’s like, ‘Come on, just ‘fess up. You need to tell them.’”

Baby June arrived around 10:30 p.m. Sunday, weighing in at 7 pounds, 13 ounces.

Miller’s husband says it isn’t his wife’s first “extreme” pregnancy adventure. A couple years ago, while pregnant with her son, Caleb –- now 19 months — she hiked to the top of Machu Picchu.

He did the marathon route with his wife Sunday but managed to lag behind her by 19 minutes. 

“Personally, I was in a lot of pain,” he said, joking. “I was thinking about me a lot.”

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