Hi Maltesefalcon,
do you have birth children? If yes, can I ask, how did you go from idly thinking 'wouldn't it be nice to have kids sometime' to actually deciding to go for it and not use contraception anymore/TTC? (Assuming that they were planned kids ;) )
I'm asking because I found it to be quite similar. With BC I always new I wanted to have kids sometime but the time was never right, then all of a sudden (like Lilka said) I just started feeling this need. The time still wasn't right but I didn't care anymore ;) We then did look into adoption but were put off because it seemed so very hard. I wasn't confident enough about my prospective parenting to jump in at the deep end. Adopting is, I think, the hard way to 'get' a child, and also very likely to be more challenging once the child is at home with you.
After having DS, it was similar. I still knew that we'd sometime like to have more kids. I still knew that we might adopt; it had actually become more likely, for various reasons, that we'd choose adoption over having more BC. But anyway, the time wasn't right. And when you have BC, the time when it is right to adopt is not just determined by yourself anymore, the agencies have a lot to say about it too!
So my 'idle' thinking that we might adopt sometime grew to be a bit more specific, and when DS was about 9 months old I started really reading up on things. Then lay it to rest again. Then picked up some more books a year or so later. Then lay it to rest again. And so forth...
Now that DS is nearly 3, I started feeling the 'urge' again. What I really needed was to find out if we 'could' adopt, if they would let us at all - even if not right away. Because if 'they' (SWs etc.) wouldn't let us adopt, then we would want to have another BC and for that, due to age and such, time is sort of running out. Also I wanted to explore in more depth if it really is what we want. To avoid waiting another 2 years, then finding out that actually upon closer reflection we don't want to adopt, then finding that we can't have BC anymore either. So that was what made me make the move from 'idle thinking' to talking to LAs/agencies, reading specific books, posting on here, etc. And that's where we're at now - at the start of the process!