Have you taken ovulation tests or charted your BBT (body temperature)?
You may need to go back to the doctor and have some assistance.

When this happened to me, my doctor had me chart my BBT for about 3 months to see if there was any pattern. I also was without a period for months. He gave me Provera to start my period, to be followed by Chlomid. I was successful in getting pregnant after a few rounds of that.

When was the last time you went to the Dr. You may want to go back in and explain that you have been trying unsuccessfully and ask what his/her next steps of recommendation are.

Do a Basal-Body-Temperature. Charting it over a few cycles can give you a good idea of when you are likely to be ovulating. Do an internet search on "Basal-Body-Temperature" - lots of information out there.

Try Zuri's suggestion. The Provera starts your period, but not your ovulation. The Chlomid would aid in ovulation.

As for the BBT (Basal Body Temp) There are special thermometers for this. In the US, they have BBT kits, with a thermometer and chart and directions, etc.

I hope this helps.

Getting assistance from your doctor will definitely help. Although most women who have irregular periods usually have a hard time conceiving, just do your best and don't give up.

Just keep on going to your doctor and dont lose. Just keep on praying that God will give you one. Nothing is impossible with HIM. Irregular periods will definitely be hard for you to conceive but just try and try and ask advice from the expert and pray also.

Good for you that you have giving up smoking and drinking. It's a great start and don't lose hope. With your irregular period, ask the doctor for something to drink to normalize your monthly period. Just continue to do things properly and in healthy way. Try and try until you will have it.

BC pills should have made your period regular and you should have gotten pregnant by the time you're off with it. ask your doctor for other options or treatment that will help regulate your period.