One of the most common concerns that some women have when trying to conceive is if their periods are irregular. Indeed, it’s rather common for women to have irregular periods. When your period is irregular, it doesn’t mean that you can’t conceive. What it means is that it’s going to be a little bit harder to plan for conception and to track when exactly it is during the month that you’re ovulating. The more irregular your period, the harder it will be to predict.

It’s important to understand, as well, that not every woman’s period is exactly 28 days. Some women have regular periods every 30 days, or every 26 days. When your cycles are the same number of days each month, it’s not considered “irregular” and may be easier to time your conception efforts.

There are a number of different things that can cause you to have irregular periods. For example, periods of high stress, or times when you experience a dramatic degree of weight gain or weight loss can interrupt your cycle. There are a number of medical conditions, as well, that can interfere with how regular your periods are. PCOS (polycystic ovarian syndrome), certain thyroid problems, ovarian dysfunction, irregularly high levels of prolactin can all lead to irregular periods.

If you think your cycle may be irregular, the first thing to do is to track it. Keep a record of how long your cycle takes each month. Do this for at least six months. Then, take the shortest cycle and subtract 17 days from it. Subtract 11 days from the longest cycle. Those are the days of your cycle when you’re going to have the best chances for conception.

As always, if you’re struggling with conception, it doesn’t hurt to talk with your doctor about things that could be interfering with your fertility.