Completing the Female Athlete Triad: Spotlight on Amenorrhea

The final side of the triad: amenorrhea. Image from


It sounds like a stomach virus, doesn’t it? It’s not.

In case you’ve missed the first few posts on the female athlete triad (read them here and here), amenorrhea is the absence of a period for greater than 3-6 months. In other words, when Aunt Flo stops visiting. Sometimes amenorrhea is normal and without many side effects, such as during pregnancy, breast-feeding or menopause. Other times amenorrhea is a sign that something in the body is amiss. The reason we’re talking about amenorrhea here is that running can indirectly lead to amenorrhea through energy deficiency.

How does something so good for you, i.e. running, cause something so bad for you?

Picture this: You’re training for a fall race. You’re working hard and are in phenomenal shape. The best of your life. You are taking care of your body by eating a well-balanced diet. Maybe you’re focusing on cutting out processed foods or after-dinner sweets. Four or five weeks pass and you think, “Hmm. I haven’t had my period in a while.” If your pregnancy test comes back negative, you may be thinking, “sweet, no monthly hassle! This is great!” You keep training hard and eating right. Maybe you’re getting a little too restrictive with your diet. Maybe you’re training a little harder than your body has prepared to train. Another 4 weeks go by. And then another. And then another. You’ve probably forgotten by now that you haven’t had a period in 4 months. You’re amenorrheic.

If you’ve never had a period and are over 15 years old, this is primary amenorrhea. If you’ve previously had a normal period, this is secondary amenorrhea. But these are minor differences; both are signs that your body is out of balance. Both increase your risk for a stress fracture to more than three times that of someone without menstrual disturbances. And ultimately, both jeopardize your longevity in the sport of running.

Make no mistake, despite the seeming benefit of not having a period, amenorrhea is a sign of a serious problem.

Primary amenorrhea can be slightly more concerning because, according to the NIH up to 90% of peak bone mass is built before a woman reaches 18 years old. If three of those years are spent in an amenorrheic state, bone mass is actually being lost instead of being built. The bone loss is often irreversible.

Primary amenorrhea can also be harder to detect because the patient (and others) may just think she’s a late bloomer. Meanwhile, her bones are deteriorating from healthy to osteopenic to osteoporotic. All before she enters college! Yikes! I had two friends/teammates in college who had primary amenorrhea as high-school athletes. They both endured 4-6 stress fractures in less than four years which significantly impaired the development of their talent and their enjoyment of the sport.

Stress fractures… a runner’s worst nightmare! Image from

Secondary amenorrhea also causes loss of valuable bone mass with every period-free month that passes. After the age of 30, bone mass naturally begins to decline. Couple this with calcium and bone loss due to amenorrhea and you have one big fat risk factor for osteoporosis. My future-minded brain now feels the need to tell you that this can affect you both in the short term (stress fracture) and the long term (broken bones and osteoporosis 30 years later).

Secondary amenorrhea can also occur in conjunction with luteal phase suppression, and both can be the result of an energy deficiency.  Luteal phase suppression is shortening of the phase after ovulation and before either implantation/pregnancy or  your period. During luteal phase suppression, the body produces decreased progesterone and the lining of uterus is shed prior to implantation. This can result in shorter cycles and can result in infertility. I do not want to confuse you, however, as this is not, in any way a correlation or causation between running and infertilityNot in any way.

And when it comes to secondary amenorrhea, luteal phase suppression is much less common than bone loss. Bone loss is just about a guarantee.

What can you do to prevent or reverse amenorrhea?

1. Talk to a doctor. If you go without a period for 3 or more months, it is a good idea to mention it to a medical professional. Energy imbalance is not always the culprit and you may want to have everything else cleared before you blame your healthy habits.

Everything you need to know, you learned from Sesame Street. Image from

2. Test your body fat. References say that women who fall below 15-17% risk amenorrhea. Since every body is different, it may be a good idea if you are concerned about your risk for amenorrhea to test your body fat regularly (every 3-6 months). That way, you can see if you have a threshold value that corresponds to loss of menses.

3. Get enough energy and EAT! Running is an avenue for weight loss for a lot of women, both intentionally and unintentionally. But weight loss can be a slippery, slippery slope. If you’ve become amenorrheic, it’s a sign that your eating habits may be headed towards detrimental or disordered patterns.

4. Train a little less. If you would have given me this advice 1 year ago, I’d have said “yeahhhhhhhhh right.” But long-term health is more important than any running goal. If you aren’t healthy, you won’t have longevity in the sport. So take a month, decrease your volume and intensity and see if your body returns to normality. It’s good advice for anytime things seem amiss.

Have you experienced amenorrhea? What advice do you have for keeping your healthy habits in check?

I'm a pediatric physical therapist by day. Running mostly early am miles as I balance life as the mom of a toddler. With PR days in the past, my primary running goal is to be a lifelong runner. With 20+ years behind me, I still love the sport and I am truly grateful for every day I get to run.

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  1. I’m a little paranoid about maintaining energy balance since I’m techically in the atypical (can’t bring myself to say abnormal) zone when it comes to bmi/bf%, so call me crazy, but I love getting that little confirmation every month that my body is functioning. i actually think it’s one of the nice things about being a FEMALE athlete is getting that feedback, and it’s one thing i didn’t like when i tried bc.

  2. I agree with Paige. I also hated BCPs for this reason. It’s nice to know what’s going on!

    I also think it’s great you mentioned the luteal phase defect. My cycle starts getting short and I sometimes get spotting over the second half of the month when I’m training hard. I’ll go from a 28-30 day cycle down to 23-26 day cycle with some intermittent spotting over the last week and a half. If I taper or otherwise cut-back my cycle goes back to 28-30 days with no spotting. I doubt it’s a coincidence that I’ve gotten pregnant all three times during downtime in my training! I’ve never lost my period all together (except for the pregnancies and post-partum periods) though, but the shorter cycles and spotting freaked me out and clued me in that I needed to be on high alert. As annoying as a period can be, especially when you get it race morning (the. worst!) I also know better than to do anything other than appreciate it and the indication that things are going ok with the ol’ bod.

    Great post!!!

    1. birth control/birth control pill.

      i have avoided bcp since i was young for this exact reason, the body is meant to behave a certain way and if it isn’t behaving right I want to know!

      Great series Rosemary!

      1. Aha, thank you. Dumb follow up question – how would that have anything to do with amenorrhea? Or are you all suggesting birth control would eliminate your cycle?

        1. BCPs regulate your cycle so can mask issues with your cycle. By not taking BCPs we can use our cycles to see whether things are right with our bodies in terms of things like amenorrhea or the length of our cycles, whether we’re ovulating, etc. Those issues in themselves aren’t necessarily a problem, but symptoms of other problems like infertility, bone health problems, etc. Obviously, there are benefits to BCPs! But, this is one downside, at least in my opinion 🙂

  3. Hmm. I have an IUD and love it. I don’t worry about pills or shots, don’t get a period at all any more, and honestly I don’t EVER want to go back if I can avoid it!

    But because of this post I’m definitely going to bring up the athlete thing at my next GYN appointment. I never really felt like it was necessary for my lady doctor to know I was a runner but now I absolutely see the importance!