Your friend is going to be emotionally and physically exhausted, after hearing the news and going through labour I expect it only really hit her when her daughter was born, up until that time you sort of expect a miracle and hope that your baby/babies are ok (despite what the doctors say). I lived for the minute when I thought I would hear them cry. I cant describe the feeling of walking out of a postnatal ward where you are surrounded by the sound of babies, with empty arms.
For me I didnt really accept it until the funeral a few weeks later during which time i didn't eat, sleep or speak to anyone. What i did find helpful were Sands, they are amazing if you could ring up and explain they will send lots of helpful information, leaflets etc that which your friend will find useful just leave the information in an envelope. She will find comfort from them and also at a later stage she may feel ready to talk to a befriender, who has experienced the samething and will visit her at home and sit and talk to her. For me to talk to someone who actually understood how I felt made all the difference.
I found phonecalls an irritation to be honest, but please ring as although she may not talk to you, through the numbness its nice to know someone cares. I found that cards or letters from friends were good as I could read them in my own time. One thing you could do is get her a special candle, I lit two each day at the time of birth, it made me feel better, although it may not work for her but many mothers tend to do this for their lost beans.
Please remember the due date (as well as the birthday) she will feel especially low at this point and if you could get a pink teddy (I felt more appropriate for a baby than/as well as flowers) for the day of the funeral, I think she would be very touched.
Please
1)do not say you can have another baby, you could try again or least you have a child already.
2)do not try and get her talk before she is ready
3)do not forget her husband as he will be trying to be strong but will obviously be a wreck also.
4)If she wants to talk about her daughter encourage her, ask if you could see the photos, hand/footprints if she wouldnt mind. Oh I just thought perhaps a lovely picture frame would be a thoughtful gift.
Anyway hope this helps, my heart goes out to your friends.