How long does it take to start ovulating and ';prepping'; for pregnacy after being on birth control methods?

I have been on both birth control pills and the depo shot for the past 4 years. When I talk to certain people, they say that it can take at least a couple of years to get a ';normal'; menstrual and ovulation cycle. However, I am getting my period every month like I am supposed to, is it still unlikely for me to get pregnant since I've been on BC for so long. Has anyone else experienced difficulties with having a child after being on BC??How long does it take to start ovulating and ';prepping'; for pregnacy after being on birth control methods?
if you chart your basal temps for a couple cycles and see an obvious shift in temp aprox 14 days before you get your period you will know you are ovulating.





Basal temp: temp right when you wake up before you do anything, keep your thermometer (digital or glass oral only) next to your bed as soon as you wake put it in your mouth and don't move till it's done, should be done at the same time everyday or there may be variations.How long does it take to start ovulating and ';prepping'; for pregnacy after being on birth control methods?
All women are different. Some do not have any problem returning to a normal cycle and can start trying right away. some women take much longer and have fertility issues.