With my first I used to go every week for 6 months, then fortnightly and then monthly by 12 months. With the rest I didn't bother as much because I just couldn't be bothered LOL. Probably would have been once a month. With DS2 though I went every 2 weeks for a bit and then monthly. By the time you have #4 you probably don't need to go as much, but I like the MCHN and didn't mind just going in for a chat and a catch up.