It can be hard to watch someone you care about go through a difficult time. Whether it's a dangerous pregnancy, a traumatic birth experience, the loss of a child before or after birth, you don't want them to feel pain or sadness. You just want to take it away and make them happy again.
Or maybe you don't even understand why they're upset. If you had gone through something like that, you don't think you'd have reacted this way, so why is it so hard for her? Why hasn't she gotten over it yet?
No matter what you say, you can't take away another person's pain. She has the right to feel what she feels. She will work through it in her own time and her own way.
There are, however, at least two things I would recommend against saying.
1. "At least..." At least you have a healthy baby. At least you know you can get pregnant. At least you don't have to get up in the night to take care of your baby (actual quote said to a grieving mother who lost a child!).
Never, ever, say at least. I'm sure it's said with the best of intentions: if only she can look on the bright side, she'll be happy and won't be in pain any more. But what it really sounds like is "The bad thing you went through wasn't *that* bad. If X had happened, then you'd have something to be upset about, but you have no right to feel bad about the not-so-bad thing that happened."
Grief is not a competition. Something bad happened. She has the right to feel what she feels. "It could have been worse" doesn't change that.
Now, if the woman herself wants to look at the bright side, that's great! It's a good sign of healing. But it's not something she can be forced into before she's ready.
2. Any variation of "It's God's Will." God has a plan. God will use it for good. God is teaching you something important.
This may come as a surprise to people who know me in real life, and I may even offend some of them with this. I am a committed Christian. I do believe things happen according to God's plan. I do believe God will use bad things for good. I do believe God can use it to teach us something. I still find it upsetting when someone tells me this.
Again, I'm sure it's said with the best of intention. You can take comfort in knowing good will come from the bad, right? But "It's God's will" sounds like "You aren't allowed to feel bad about the bad thing that happened. How dare you question God?"
Jesus Himself felt sadness. Jesus Himself felt anger. Dare I say, He even felt fear. If the Son of God can feel these things, surely I can, too. Trusting that God has a plan doesn't automatically end those emotions. I can take comfort in trusting God's plan while still feeling and working through my pain.
So what should you say? As I said before, nothing you say will take away the pain. BUT a little empathy can go a long way. "I'm sorry" may sound trite and cliche, but it acknowledges what happened and allows the woman to feel what she feels. "I'm sorry you had to go through that. It must have been hard."
I'm sure there are other things that people found helpful or upsetting. Feel free to comment and share your thoughts.