expert advice MORE
Irregular Menstrual Periods
Q: My daughter is 14. She is very athletic. She plays basketball. She got her period for the first time in August. She has not had it since. Our pediatrician told me before not to worry about her not getting her period. He said as long as she's developing properly we have nothing to worry about. I'm just concerned that she hasn't gotten it back. How long should I wait until I should be worried?
A: Although I understand why you might be worried, it sounds like you need not be. When strenuous exercise begins before the first period (menarche), each year of training actually delays the onset of menarche by about 5 months. The average age of menarche in the United States is about 12-3/4 years, so your daughter is within the normal range.
She also has more than one reason to be having irregular periods at this stage in her life. First, it is common for girls to have varied periods for up to two years after they have their first period, with more than half of their cycles not releasing an egg (being anovulatory). These different bleeding patterns may include several months in a row without any period, especially during the first year after menarche.
Secondly, athletes often have varied menstrual cycles due to substances in the brain that suppress a gland in the body that produces hormones (the hypothalamus) which causes no periods (amenorrhea). I do not know how athletic she is or how intense her participation is in sports. However, the lack of periods in your daughter, like other athletes, is felt to be associated with the intensity of her exercise, her body weight, and how much body fat she has. A body fat percentage of 22% is considered necessary to maintain regular periods.
In sum, your daughter seems to be having normal pubertal development. Having no periods (amenorrhea) for the last few months may also be normal. If your worries continue, discuss it further with her pediatrician who can complete a history, do an examination, and consider checking for other less likely explanations.
More on: Expert Advice
Henry Bernstein, M.D., is currently the associate chief of the Division of General Pediatrics and director of Primary Care at Children's Hospital, Boston. He also has an academic appointment at Harvard Medical School.