I had been on the pill for about 9 years (a little on and off but definatly on for 3 years solid) when we decided to start TTC - I waited until I had my period and then did not take any more of the pill, I got my period once, within a few days of when it should arrive and then I fell pregnant the following month. In the past when I have come off of the pill (although not for TTC reasons) it has taken me 6-8 weeks to regulate.

I hope your wait isn't to long

As far as weight gain goes... after many years depending on the pill I did not gain any weight when I stopped taking it