Hypothalamic Amenorrhea, Explained
Not getting your period might sound like a wonderful change, compared to sometimes painful visits from Aunt Flo every month. But irregular—or missing—periods aren’t normal, and can bring significant health risks both now and in the future.
I was somewhat of a late bloomer, starting my period at fourteen. But even though I was a few years later than most of my friends, that was still considered normal. That year, I had my period exactly twice. After that, only about once every year or two…until I was twenty. That was not normal.
The reason my period disappeared for so many years was due largely to my struggle with an eating disorder. When we under-eat or over-exercise (or in my case, both), our bodies rightly assume that it’s a dangerous time to have a baby. So, our brain signals to our ovaries to shut down the reproductive cycle until things aren’t so stressful.
Throughout those six years, my weight cycled up and down a lot. There were times that I was significantly underweight, times I was at a healthy weight for my body, and times that I was above my weight set point. But in all of those cases, my period was missing because of stress. Even though I was in a bigger body than I am now, bingeing every night, my body was under stress because I was starving myself most of the day. Even when I was eating enough calories, I was restricting my diet so much by “eating clean” and limiting carbs (a stressful experience) that my body didn’t have enough resources available to produce fertility hormones. Even when I was eating more carbs and enjoying desserts on occasion, I was running so much that I overworked my body into allostatic overload.
I didn’t get my period back until I recovered from my eating disorder—and I mean really recovered. Not the clean-eating obsessed, workout-tracking, monthly-weigh-in-type of quasi-recovered state I hovered in for so long. Real recovery…which meant taking a break from exercise for nearly two years, eating ice cream every day, and getting rid of my scale. And my back-up scale.
And finally, five months later, my cycle returned. I’ve had a period every month since.
The hypothalamic-pituitary-gonadal axis (HPG Axis)
The diagnosis my doctors gave me for my missing period was “anorexia nervosa” (followed by “female athlete triad” and then “bulimia nervosa”). But taking a look at the physiology explains why amenorrhea (missing period for 3 months of more) accompanies eating disorders and over-exercise syndromes.
When it comes to reproduction, it starts with a part of our brain called the hypothalamus. When a person is healthy, the hypothalamus releases a hormone called gonadotropin releasing hormone (GnRH) which communicates with the pituitary gland. The pituitary gland, in turn, sends out its own set of hormonal signals (follicle-stimulating hormone and luteinizing hormone), which tell the ovaries to mature and release an egg, prepare the body for a possible pregnancy by thickening the uterine lining, and finally, to shed the uterine lining if a pregnancy doesn’t occur. You know, everything we learned about in sex ed.
But if we aren’t healthy—whether because we are under eating, over exercising, or otherwise suffering from stress overload—this hypothalamic-pituitary-gonadal axis gets interrupted. The hypothalamus and pituitary stop sending out their signals, shutting down the hormonal cascade that triggers ovulation. Without ovulation, there is no fertility. Period.
It’s not about the number on the scale
It’s important to realize that hypothalamic amenorrhea isn’t just a problem for individuals struggling with anorexia. Disordered eating of any kind, even if a person is at a normal weight or a weight above their own set point, can trigger irregular cycles. The same can be said for individuals of any weight who are under excess stress, whether from emotional, psychological, or physical causes.
Amenorrhea was no surprise to me when I was a teenager. Since I’d been battling an eating disorder for so long, I knew why my period was missing. In the early years, I figured it was because my weight was so low. In the later years, I never actually stopped to think about why Aunt Flo was still MIA. But frankly, I didn’t really start to care until my doctor prescribed birth control pills, as I wasn’t anywhere even close to thinking about having a baby.
I experienced a monthly bleed for the few months I was on the pill, but it went away again once I stopped taking it. (This is because the synthetic hormones in the pill mimic the body’s natural rise and fall of estrogen and progesterone, followed by 7 days of placebo pills. This leads to what’s called a withdrawal bleed, and corresponds to the “period week” when taking the pill. However, birth control pills, by nature, prevent ovulation. Since I wasn’t ovulating on my own before the pill, and my body wasn’t healthy enough to ovulate on its own after I stopped the pill, my period didn’t resume once I stopped taking the contraceptive.)
By the time I entered real recovery, I was above my weight set point due to nightly binges. When I stopped pursuing weight loss (and worked through my body image struggles), my urges to binge evaporated. I actually ended up losing weight…and then my period returned. Hypothalamic amenorrhea is related to weight in that a low body weight can cause us to experience irregular or missing cycles. However, low body weight isn’t the only cause, and it isn’t even the most common cause.
Health Risks of Hypothalamic Amenorrhea
As I mentioned above, a missing period might make life more convenient, but it isn’t healthy. Our sex hormones (estrogen, progesterone, etc.) play a bigger role in our health than just getting pregnant. In fact, sex hormones affect the health of just about every system in the body. When we aren’t producing enough of these hormones (the physiological explanation for hypothalamic amenorrhea) our health suffers in countless ways. Here are just a few:
- Low estrogen: The most well-known risk of chronically low estrogen is osteoporosis. Estrogen maintains bone density, and low estrogen leads to weakened and brittle bones. Estrogen also influences memory, fine motor skills, coordination of movement ,and mood. Low estrogen can also increase the risk of neurodegenerative disease, chronic pain syndromes, and unsurprisingly, infertility.
- Low progesterone: Low progesterone can lead to depression, cognitive disorders, loss of muscle mass, heart arrhythmia, elevated cholesterol, neurodegenerative disease, and neuropathy.
- Low testosterone: Low testosterone in women is associated with low libido, anxiety, depression, fatigue, and loss of muscle mass. Deficiency is also understood to contribute to cardiovascular risk.
The moral of the hormone story
Hypothalamic amenorrhea is a serious health problem, even if fertility isn’t anywhere on the horizon. Self-care is super important in women’s health, and problems like under eating, over exercising, and stress overload can have devastating consequences down the road.
[If your period is missing and you don’t know why, talk to your doctor. I also offer services in natural health, and I can help you identify the underlying cause of your symptoms, too. I’ve worked with countless other women in this area, and I’d love to help you, too. Learn more about my services here.]
- S. C. Manolagas, S. Kousteni, Perspective: Nonreproductive Sites of Action of Reproductive Hormones, Endocrinology, Volume 142, Issue 6, 1 June 2001, Pages 2200–2204, https://doi.org/10.1210/endo.142.6.8221
- Taraborrelli S. Physiology, production and action of progesterone. Acta Obstet Gynecol Scand. 2015;94(Suppl 161):8–16.
- Davis S. Testosterone deficiency in women. J Reprod Med. 2001;46(3 Suppl):291-296.