How to know that youre fertile if your menstruation is irregular?

Infertile: Just because you have irregular menses, it does not mean you are infertile. Many women who have irregular periods, are able to get pregnant. It may take longer time to become pregnant. There are multiple other causes of infertility. Usually, you do not have to worry, unless you have been trying for at least a year with good education on ovulation and with having the male partner tested first.

Well...: Depending how irregular your period is you need to keep a calander for 3months. If the irregularity is more than 7 days each cycle you should see a doctor, OB or fertility dr to help you regulate your menses and help the need for ovulation. If the problem is only a few days difference get an otc ovulation kit and follow the directions to see if you are ovulating.