Weight gain causes amenorrhea because...?

June 22, 2009 4:45 PM

How does weight gain cause you to stop having your period?

I was on two medications that cause "massive weight gain." I have since come off of them, but in the meantime, I gained about 30 pounds in about three months. As a result, I have not had a period in 90 days or so. I've been to my GP, who ruled out all the thyroid/anemia/bloodwork-related causes. I have been to my gyno, who pretty much just said, "it's the weight gain."

So now that I know the cause, I'd like to know how it works. Why does weight gain or loss cause changes in your period? It's my understanding that I am probably not ovulating, and that's why my period isn't happening, but why does obesity cause anovulation?

And, finally, if I am not ovulating, is there a lesser chance of a horrible, month-long period when it finally does come back? I'm sure hoping so.

posted by starbaby to health & fitness (9 answers total)

Rapid weight gain produces a lot of stress on your body. Stress hormones can keep you from ovulating.

Or, at least, that's what I'm assuming is happening. IANAD.

Probably not a month-long period, but whenever I missed mine for stress related reasons, it was always accompanied by painful cramps.
posted by dinty_moore at 4:49 PM on June 22, 2009

why does obesity cause anovulation?

Obesity doesn't cause anovulation: lots of people who weigh whatever you do right now have their period every month like clockwork.

It's the sudden change that disrupts the cycle. If you've weighed 300 pounds for years, your reproductive cycle is almost certainly adjusted to that, but if you go from 150 to 180 in a very short time, that can screw the cycle up for a few months.

This is a way in which weight gain has a different effect on ovulation and fertility than weight loss does--many people who are consistently at a low body weight consistently have impaired ovulation and fertility, but to find a comparable group of folks with the same percentages of impaired ovulation and fertility function, you have to go way way way up on the obesity charts to the "super-obese" category.
posted by Sidhedevil at 4:54 PM on June 22, 2009

Ovulation is regulated by hormones. Body fat, either too much or too little, seriously messes with hormonal balance, to the point that both obese and significantly underweight women can experience either irregularity or complete lack of ovulation.

Basically, both under-nutrition and obesity can cause a host of endocrine imbalances, some of which have nothing to do with ovulation, i.e. diabetes, but they can both also cause hypothalamic-pituitary dysfunction, which directly affects estrus.

That isn't the only reason you might experience amenorrhea though. Stress can cause it, even the reputedly "good stress" of regular, strenuous exercise. An old girlfriend of mine ran track, and she could sometimes go for an entire season without having a period. It probably helped that she was also skinny as a rail and so kind of borderline to begin with, but the two things together just shut that down completely.
posted by valkyryn at 4:58 PM on June 22, 2009

leptin
posted by NucleophilicAttack at 4:59 PM on June 22, 2009

both obese and significantly underweight women can experience either irregularity or complete lack of ovulation.

This is true, but the levels of obesity that can create that issue aren't the levels of obesity one could get to from a WHO-defined "healthy weight" by gaining 30 pounds.

In this case, it's almost certainly the sudden change, not the OP's particular scale weight.
posted by Sidhedevil at 5:06 PM on June 22, 2009

estrogen, among other things.
posted by sero_venientibus_ossa at 7:26 PM on June 22, 2009

Sidhedevil: I'd probably agree with that assessment, as that comports with my admittedly limited medical knowledge and broader impressions that yes, obese women regularly get pregnant without too much difficulty.

Still, the reason is probably what I outlined above: stressors, including relatively rapid gains of relatively small amounts of weight, can produce amenorrhea and do so in much the same way. But yes, unless the weight gain is really, really big, the situation is likely to resolve itself once the body adjusts to its new status quo.
posted by valkyryn at 7:47 PM on June 22, 2009

As explained by my doctor, fat absorbs estrogen -- so rapidly gaining and losing weight can mess with your hormone balance, and that can mess with your period. Eventually, outside of extreme weights in either direction, things will work themselves back out again.
posted by jacquilynne at 8:07 PM on June 22, 2009

Not so much an ´I know' as, google these terms...
Extra fat causes hormones (estrogen) to go out of wack, hormones out of wack causes anovulation, itś often part of the mechanism causing PCOS, aside from genetic susceptibility etc..
If you google PCOS and losing weight, it might explain why that happens?

(And sorry for weird characters, my computer is stuck on international settings... :P)
posted by Elysum at 5:00 PM on June 23, 2009