DOUBLE BONUS: What not to tell an expecting friend in her last trimester. Don't's
This is a classic and I'm going to be straightforward here (like they say Dutch people are...). Don't ask her if the baby has already arrived. Just don't. Because the baby hasn't arrived yet. Otherwise, you would've surely heard about it. She's just as anxious as you are to meet this little one and it's not helping her a bit if all those impatient, but well-meaning, friends and relatives keep reminding her that it takes so long. She already knows that.
Another one, which might not apply to all pregnant women in their last trimester but can be very helpful for those to whom it does apply... Don't ask her what she needs. This might seem strange as you want to help and need some place to start. But, her brain is probably so foggy and trying to focus on her baby and the upcoming delivery that she doesn't know what she needs.
Surely, she knows she wants to rest and prepare and tidy the nest. But how and when? She has no clue.
So, just bring that meal, her favorite treat, and send those flowers as an encouragement. Without asking if she needs them. Trust me, as a five-time "third-trimester graduate", she will definitely appreciate your efforts.