Irregular periods during the teenage years have never been much of a cause for concern. It was thought that young girls might have a few years of irregular periods before their reproductive systems settle in to a routine. But new research has proven that theory wrong and found a link between irregular periods in the teen years and more disturbing health problems later in life. The new study, published in the journal Fertility and Sterility, found that irregular periods during the teenage years may be linked to obesity and may also be an early indicator of diabetes and heart disease later in life.

Dr. Charles Glueck of the Cholesterol and Metabolism Center at the Jewish Hospital of Cincinnati and his colleagues followed 370 girls, starting at age 14, who were part of a larger study initiated by the National Heart, Lung, and Blood Institute. Once a year, the girls were asked about the regularity of their menstrual cycle while the researchers gathered info on the girls' height and weight and measured their hormone levels, glucose, insulin and blood pressure. For the purpose of this study, irregular periods were defined as those lasting more than 42 days (meaning more than 42 days between the start of one period and the start of the next.) 

After putting all the information together, the study's authors found that girls with the most reports of irregular periods were already heavier than the others at age 14, and gained more weight and inches on their waist throughout the study than girls whose periods were regular. The girls who reported irregular periods also had higher levels of testosterone. By age 25, these same girls had a much higher BMI (body mass index) and higher blood sugar than girls whose periods were regular.

Did the irregular periods cause the weight gain and blood sugar increase? Or were they simply an indicator of oncoming health problems? It's too soon to tell. But this study does give a good indication that doctors should be on the lookout for irregular periods in their young patients so that they can step in with early prevention measures against diabetes, obesity and heart disease if necessary.