email. 100%.
so she will have time to read it be angry/upset/jealous etc. and process it on her own time.
It will give her time to deal with her emotions.
GL!
IMO, if you have a friend that like that is so close i would avoid rubbing it in her face, like facebook nothing worse than seeing contant posts about your pregnancy and u/s etc.
ETA: I was kind of on the other end. I suffered a loss, and the next week my SIL announced she is pregnant at my grandparents dinner with all our family. needless to say i left hysterically crying. shes an asshat by nature so im not surprised, but being in those shoes i would prefer someone tell me via email or text so i can cry and be upset but then approach them with smiles and be happy for them.
MOST PEOPLE thankfully havnt had a loss or struggle with getting pregnant, so they would not be able to relate to being on that side. I can already tell by some of these responses to the post.