Thank you for your advice and encouragement on my last post. I did e-mail my friend, and it turned out I was right - although obviously I'd rather have been wrong.
She responded very quickly and told me about the devastation she and her husband had suffered when they lost a very much-wanted child quite late in the pregnancy. She also told me that her son was conceived through IVF.
I'm so sorry for the pain she's had to go through, but really glad that I made that contact - it's so easy to do nothing in these circumstances, but with your help it took me less than a minute to compose an e-mail which has opened up a line of communication and hopefully made her feel that someone else cares about what happened to her.