Aspirin and menstruation.

Does taking aspirin for cramps and other discomfort during menstruation ‘thin’ the menstrual flow as it supposedly does other blood?

In my experience, yes - no more and no less.

Aspirin and other “blood thinners” is a mianomer that bugs me no end. They do not make the blood any “thinner”, whatevert that means. What they do is to interfere with the clotting process, resulting in longer bleeding times from cuts. I would imagine that there might be some effect on menstrual flow, but it would be so small as to be unnoticable.


Oh, my no, it is NOT so small as to be unnoticable. Believe you me. We’re talking “abbatoir on the lunch grounds.” This effect was one of the greatest epiphanies of my late teenage years.

Menstrual blood tends to clot more slowly than blood from a cut anyway - asprin definitely has an effect, although that will vary somewhat from woman to woman. It’s noticable. Trust me.

Most of the things i’ve read on the subject of pain meds for cramps (repuitable sources like Cosmo, iVillage and WebMD :rolleyes: ) suggest an anti-inflammatory like iburpofen (Advil…motrin…) and not asprin or tylenol. The pain is in the inflamation. nip it!

Ok, mea culpa. Being a guy, I have no first-hand experience with this, so I yield to those who know better than I/ I’ll put this away in my “fun facts.”


As a person who suffers from both heart and menstrual problems (one causing the other, I believe) I was told to quite emphatically to NOT take asprin while I had my period by my doctor.

So, another vote for Yeup, it does “thin” your blood.

:: furrows his brows in confusion ::

I’m no expert on girly-parts, but isn’t menstrual fluid not actually blood but uterine lining? I didn’t think clotting was necessary, because it’s just the lining of the uterus (albeit blood-rich.) If you take a blood-thinner, does the uterine wall keep bleeding after the endometrium (or whatever it is) falls off?

Do you really wanna hear about my bleeding problems? Because I will tell you if you really, really wanna know.

No, hon - a lot of the pain is in muscle cramps, hence the term “menstrual cramps”. Anything ranging from a mild ache to a knock-you-over charliehorse spasm.

Inflammation is also a factor, yes, but they really are CRAMPS. Uterine wall muscle contracting and all that.


It’s BOTH. It’s uterine lining AND blood, some of which actually can clot into nasty lumps, along with a fair bit of vaginal mucus.

The uterine lining grows into this spongey stuff due to a rich network of small blood vessels. At a certain point, these pinch off, starving the squishy uterine tissue and killing it. Then they re-open and break off, the resulting blood helping the tissue to slough off and leave the vicinity. It’s not usually gushers and geysers, but the uterus really does bleed until the little blood vessels seal off and the cycle starts over.

So, blood thinners or not, the uterus does bleed after the endometrium (you had that correct) falls away. Likewise, the uterus bleeds for some time after childbirth, after the placenta peels away and is expelled. It is rare, but menstrual bleeding can become life-threatening if the volume lost is excessive or the blood refuses to clot at all.

I’ve heard that ibuprofen and acetaminophen don’t really act as anti-inflammatories unless they’re used regularly for a long time. That is, taking a couple Advil now and then will only kill the pain, it won’t reduce inflammation.

However it works, ibuprofen is the only thing that’s ever done a thing for my cramps.

It is most emphatically not just lining with a little bit of blood, but rather mostly blood with a little bit of lining. I routinely pass clots the size of hen’s eggs multiple times during my period, sometimes more then once the same day. I am pretty sure the inside of my uterus is not big enough to have that much lining. It makes more sense that the bleeding just doen’t stop quickly. They are also nearly identical to clots I have had from bloody noses.

This is how I heard it described: The lining needs to be shed, so hormones cause it to be jettisoned from the uterus, which causes bleeding. This is not like when you grow more skin, but more like when a blister forms and there is a raw area underneath. The uterus bleeds to wash away the lining and other cruft drug in by visitors. The uterus may cramp which helps it to expel the blood and lining. Having clots may be related to cramping, but the relationship is not well understood. It may be that clots building up trigger hormones to be released that cause cramping, or that the hormones that encourage cramping also encourage clotting. The same hormones that cause cramping cause the nearby intestines to cramp/speed up too causing the lovely runny stools so common during menstruation.

Pretty much all the non-steroidal anti-inflammatory drugs (NSAIDs) except acetaminophen (Tylenol) will interfere with clotting mechanisms and hence increase the amount of menstrual bleeding. It may be a small change or a big one, but most women do notice an increase. This is annoying, because most women also find that NSAIDs other than Tylenol do a far better job at controlling the discomfort associated with menstrual cramps (due to the majority of NSAIDs decreasing prostaglandin production, which typically peak at the time of menstruation and are thought to increase the uterine muscle contractions (cramping) that causes menses to be uncomfortable).

Plagued with ovarian cysts that are causing a hormone imbalance.
So I am having to take progesterone type pill 28 days a month to
better control my hormones and ensure that I bleed when I am supposed to.
It’s supposed to lighten my flow but it’s not doing the trick, but I feel liek I have to give it a fair shake before going back to the doctor.
At any rate I have always taken naproxen and or Motrin to control the pain because tylenol might as well have been a smarty candy.
So now along with all this mess, my periods are completely wacky very very heavy and when I went to the doctor this last month I had such large clots that I had labor pains while these clots which were larger than a tennis ball worked their way out.
Not having experienced that before, I freaked out and rushed to the emergency room where they put me on some hard pain killers through and IV and decided I was ok to go home 4 hours later since my iron levels are good and take vicodin and naproxen when needed for pain. I don’t really feel good about going to work on all that pain killers though… I am just thinking that the pain for me is associated with the sheer volume of these clots and have decided to take it upon myself to take Asprin this go around and see if it keeps these clots from forming at all and makes a difference.
Am I a nut or does this sound like common sense? It feels like common sense.

It seems like a reasonable approach, I personally would be worried about bleeding too much, and want to consult my doctor first.

During the first few days of my period, the bleeding can be worrisome but the clots are seldom larger than my hand when they spread out in the bottom of the bowl, and seem relatively soft. It may be that you are clotting harder and faster than I do and I can imagine where that would be painful. A few months ago I did feel labor like cramps, but that is very unusual for me and did not last for more than a few hours.


Stop bleeding out totally. There is no reason to torment yourself monthly, just turn it off until you decide you want to reproduce [or go through menopause]. Best choice my OB and I made was to just say screw trying to give me dainty little bleeds every 28 days and just say hell no to having a period at all.

That is so funny Aruvqan because my Doc put me on Nor… and It has stopped the bleeding all together. I take it between the 1st and 25th. I am supposed to bleed when I go off the medicine for those 5 days or so/ I had a follow up with Radiology and my cyst is gone but it was noticed I have a uterine polyp and they said that can cause irregular bleedign too. I was also told that the original tech who saw me that Saturday I went before was a temp, so the process they did was all together different, didn’t do the full blatter empty blatter this time.

Don’t see why he feels you need to bleed, it has been adequately documented that we do not need to bleed every month.

Glad your cyst is gone, and you may need to get the polyp checked out sometime soon.

I swear, I wish I had gotten the hysterectomy decades ago … not dealing with mood swings, hormone swings and bleeding or taking meds to supress all that crap is amazing.