This has been over a month, pay attention to your friend and make sure she isn't still in pain and people aren't aware because time has elapsed since she got the bad news. Sometimes when people have an operation or death in the family, people are really good for X amount of time and everybody goes about their business shortly thereafter while the person is still grappling with the loss.
Looks like you have gotten many good responses. I recently finished a novel about a woman whose husband lied to her back in the 60s about the second twin dying instead of allowing her to know the girl was born with Down's Syndrome. Everybody told her she should be happy about the healthy boy and everybody was avoiding talking about the girl she lost. So my advice is to not avoid talking about it. Let your friend know that you don't want to open up the wound by mentioning it if she doesn't want to talk but she can feel free to talk to you when she is feeling down about it. It shouldn't be the elephant in the room.
One of the first responses I read was about your friend getting the right baby at the right time but maybe she should consider doing foster care until that time. It takes a special kind of person to love a child like their own and then give the child back to parents when you aren't sure they have gotten it together. My stepson wound up tangled up with CPS and I was in the court room when several of those foster families adopted the children they had been caring for.
Most foster agencies are always looking for a good home for children and there are so many instances of people that can't get pregnant getting pregnant the minute they adopt. It's something to consider and fills a desperate need in most of our communities.