Hm, that's very interesting. I suppose that my eldest is a bit of a talker and tends to chat to people about things. So I assumed that as soon as she knew that she would mention things to others - I don't want to tell her that it's a secret, as that seems shameful, but private is much better, isn't it? It's then her choice. It seems as though I am mistaken anyway, and it will be a more gradual process of others finding out, as and when she wants them to.
The other thing is that if she tells people, I'd like them to talk to me about it, rather than assuming that it's taboo with me, so that I can make sure that they haven't got the wrong end of the stick about things. I feel very protective about DH. He was completely destroyed by the initial diagnosis. He felt that he had failed me. :( That all seems like a lifetime ago now, as we have our family and are very happy. But I don't want him to feel like that again if people are assuming things about him, or joke about it.
I think that the difference with IVF, or even ICSI, is that you can cover it up - people tend to assume that infertility, particularly IVF are female-factor anyway I've found. And then when the child is born, it isn't an issue any more. With DI, it has to be male factor. And if you're ignorant about the process it can seem an awful lot like the jokes of men raising children that aren't theirs, and the women pulling the wool over their eyes. Actually, that's one reason why we've not been open from the start. We wanted people to see just how lovely the bond is between DH and the children before they know, so that they can't let their predudice colour their opinion. (Also because we didn't want our children to be the last to find out.)