Q: My menstrual cycles sometimes last 40 days and other times they last 14 days. I can't calculate when to make love and I was wondering what could be wrong?

A: It's all about the BIG O (ovulation that is). Your cycles are dependent on when you ovulate; with irregular menstrual cycles, there is a good chance something is wrong with your ovulation. If you have menstrual cycles that are irregular, it's possible that you ovulate irregularly or that you do not ovulate at all. This is not so unusual, as about one in three couples who have difficulty getting pregnant have a problem with ovulation.

How can you figure out what's going on?
First, you should write down, for as long as you can remember back, when you experienced the first day of your menstrual cycle. Then calculate the cycle lengths and try finding out whether they are irregular. We have an interactive tool to calculate your cycle lengths HERE.The next step is to start doing a basal body temperature curve to find out more about your ovulation. Finally, you may have to see an ob-gyn or an RE (reproductive endocrinologist) who will examine you, review your cycles, and find out what's going on with your ovulation --whether you ovulate or if you do not ovulate at all. Bringing your fertility BBT chart with you to the first visit will help a lot and cut down on unneccessary further waiting time. You may also want to read about the symptoms and diagnosis of polycystic ovary disease (PCOS), the No. 1 cause of irregular cycles among women of childbearing age.