Are you trying to conceive? Do you have irregular periods? Do you know that about 30 % of couples trying to conceive suffer from irregular cycles due to some of the other reason? 

If you have irregular periods then there is a very high chance that you may not be ovulating and your cycles are anovulatory. But having an irregular period doesn't mean that you can't get pregnant. To get pregnant, you might need the help of a doctor to guide you on your ovulation days and to actually make you ovulate( produce an egg) with the medicines.