I didn't want to tell anyone, whereas DH wanted to tell his whole family!
We came to a compromise and we told our Mums and a couple of close friends. After we told them, it felt like a huge weight lifted and one friend in particular was a fantastic during the 2 years we were doing IVF and I was so glad I had her to talk to.
I think it really is hard to keep it to yourself, and it can definitely help to have that little bit of extra support. I did make it clear to both of our Mums that it was secret and not to ask a million questions all the time, we would volunteer information or news on our terms. It's a sensitive topic, and not nice to be regularly asked how your fertility treatment is going, especially if you're having a rough time.