From IMDb.com:
Pregnant Sorvino Did Own Stunts
Oscar winner Mira Sorvino was terrified while filming her latest action movie, because she found out she was pregnant during the shoot. The Mighty Aphrodite star was filming the mini-series adaptation of Robert Ludlum's Covert One: The Hades Factor in Canada when she found out she was expecting. Sorvino says, "There was a bit of anxiety about it because it's a very tough, violent secret agent film. Everyone was very accommodating and thoughtful. I did all of my own running, and most of my own stunts." The actress, who is expecting her second child with husband Christopher Backus this summer, is looking forward to a much-needed break. She adds, "I'm not going to work until after the baby is born. I felt like I worked a little too much last year."
I suppose they could have waited to finish filming the movie or gotten a replacement actress, but I guess the doctors figured that whatever she did was okay. Of course, Jess did all her own stunts while pregnant and the boy seems to be okay

__________________

"If you say you're going to do something and you start to do it, and people enjoy it or respect it or are entertained by it, people will step up and help you."
-- Kyle MacDonald