I was shooting during the 7-8 month mark for dove season. It's still ridiculously hot around here during dove season, so it was short lived.
She should be just fine. The baby may be on the move while she is shooting of course, and that gets entertaining. But the baby is totally safe and sound. They say if you run the vacuum a lot while pregnant, the baby is born used to the noise. So tell her to shoot away! Your little one should sleep like a rock and through any noise.
"Indeed, this seems actually to be a psychological and sociological law: the power of some needs the folly of others." -Bonhoeffer