Irregular or infrequent periods are a very common problem for many otherwise healthy women. You should talk to your primary care doctor
or your OB GYN doctor about this.
There are several medical conditions that can be associated with irregular periods, such as malnutrition and thyroid problems. However, most cases are due to something called the polycystic ovarian syndrome (PCOS).
PCOS is caused by an imbalance in the hormones affecting ovulation (the monthly release of the egg from the ovary), so that some months ovulation does not occur (and therefore the period does not occur either). As long as you are having several periods a year, your doctor may decide not to treat the problem. However, it is important to remember that you will still ovulate from time to time, and therefore you can stil become pregnant. In fact, some women with PCOS have high rates of "suprise" pregnancies because they cannot predict when they are ovulation. Therefore, birth control
may still be important.
There are several medications that can be used to improve the regularity of menstrual cycles including birth control pills and metformin, a medication usually used to treat diabetes. Talk to your OB GYN doctor to see if one of these medications is right for you.