are your periods regular now because you are on medication?
usually you are prescribed birth control pills to make irrergular periods regular.
if you want to conceive you will need to stop taking BC pills. Ideally you need to know when you are ovulating, so as to have the best chance of getting pregnant. Temperature variation is a good indicator. or changes in vaginal discharge mid cycle.

Thanks for your reply. I stopped my medication 2 years back and from then onwards my periods are regular without any problem, till febrauary 2009 my partner used condoms for birth control and from march 2009 he stopped using condoms, last month I got my period normally. I want to become pregnant, currently I am not under any medication and nor using any birth control techniques. Is the chances of becoming pregnant are positive for me?

Thanks in advance

in view of your circumstances, sounds like you have a good chance to get pregnant.
what has worked for some couples is to have sexual intercourse every other day, for a month or so to see what happens. (Except when having your period). Every other day is recommended , because it gives the man`s sperms to mature.
some try intercourse every day, or several times every day. but this means that the mature sperms get used up too quickly. A man produces 85 million sperms every day.
I wish you well in your future plans, and hope things work out for you.