# Do women urinate more when they're on their periods? **URL:** \ **Category:** Factual Questions\ **Created:** [August 17, 2013, 2:33pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491 "2013-08-17T14:33:31Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![EmilyG](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/emilyg/32/364_2.png) [@EmilyG](https://boards.straightdope.com/u/EmilyG)\ **Post date:** [August 17, 2013, 2:33pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/1 "2013-08-17T14:33:31Z")
I’m wondering whether women pee more when they’re menstruating. (And I did try to google the answer, but I just got stupid Yahoo questions like “how much blood will I pee when I get my first period” and “can I pee on a menstrual pad?” :smack:) ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [August 17, 2013, 2:36pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/2 "2013-08-17T14:36:27Z")
Minor uterine contractions, such as occur during menstruation, often stimulate the adjacent bladder and cause a sensation of needing to urinate. Not for all women, and not all the time, but it is common. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [August 17, 2013, 2:44pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/3 "2013-08-17T14:44:35Z")
Estrogen, which is highest at ovulation and peaks again a bit before menstruation, can cause fluid retention. When the estrogen level drops and the period starts, this excess stored fluid is released as urine. That’s the theory, anyhow. I can’t find that anyone’s done actual measurements and studied it in the wild, but there’s a proposed mechanism for greater urination during your period than at midcycle. From a behavioral standpoint, women will often go to the bathroom and sit on the toilet more often during their period, to check on the menstrual collection device and change it as needed. I don’t know about you, but when I sit on a toilet, I pee, whether I thought I needed to or not. So consider that even if the volume of urine is the same, the frequency may increase. ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [August 17, 2013, 3:14pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/4 "2013-08-17T15:14:32Z")
I know I sure do, for the first day or two. It’s because of fluid retention. ---
**Author:** ![Domesticated\_Primate](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@Domesticated\_Primate](https://boards.straightdope.com/u/Domesticated_Primate)\ **Post date:** [August 17, 2013, 10:07pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/5 "2013-08-17T22:07:21Z")
I thought it was because the menstral stuff still inside was reducing the amount of space available for urine storage – therefore, more frequent urination was needed. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [August 17, 2013, 10:14pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/6 "2013-08-17T22:14:37Z")
> [@Domesticated\_Primate](#): > > I thought it was because the menstral stuff still inside was reducing the amount of space available for urine storage – therefore, more frequent urination was needed. Not likely. The menstrual stuff doesn’t take up a whole lot of room. I know it seems like there’s a lot of stuff in there, but it’s really only a couple of tablespoons. Your bladder can hold about 40 tablespoons (500mL, or half a Liter), although most of us feel the urge to go when we’ve got about 20-25 tablespoons in there. So 2 tablespoons in a neighboring organ doesn’t bother the bladder much. ---
**Author:** ![Springtime\_for\_Spacers](https://avatars.discourse-cdn.com/v4/letter/s/a3d4f5/32.png) [@Springtime\_for\_Spacers](https://boards.straightdope.com/u/Springtime_for_Spacers)\ **Post date:** [August 18, 2013, 1:47am UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/7 "2013-08-18T01:47:52Z")
> [@WhyNot](#): > > Estrogen, which is highest at ovulation and peaks again a bit before menstruation, can cause fluid retention. When the estrogen level drops and the period starts, this excess stored fluid is released as urine. > > That’s the theory, anyhow. I can’t find that anyone’s done actual measurements and studied it in the wild, but there’s a proposed mechanism for greater urination during your period than at midcycle. > > From a behavioral standpoint, women will often go to the bathroom and sit on the toilet more often during their period, to check on the menstrual collection device and change it as needed. I don’t know about you, but when I sit on a toilet, I pee, whether I thought I needed to or not. So consider that even if the volume of urine is the same, the frequency may increase. Back when I still had them day four of my period was peeing day. ---
**Author:** ![gigi](https://avatars.discourse-cdn.com/v4/letter/g/a587f6/32.png) [@gigi](https://boards.straightdope.com/u/gigi)\ **Post date:** [August 18, 2013, 5:28am UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/8 "2013-08-18T05:28:14Z")
> [@WhyNot](#): > > Not likely. The menstrual stuff doesn’t take up a whole lot of room. I know it seems like there’s a lot of stuff in there, but it’s really only a couple of tablespoons. Your bladder can hold about 40 tablespoons (500mL, or half a Liter), although most of us feel the urge to go when we’ve got about 20-25 tablespoons in there. So 2 tablespoons in a neighboring organ doesn’t bother the bladder much. I’ve seen you mention this before; could you explain further? Two tablespoons at a time? Two tablespoons over the whole period? Two tablespoons of blood, not counting other materials? ---
**Author:** ![Rachellelogram](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rachellelogram/32/8689_2.png) [@Rachellelogram](https://boards.straightdope.com/u/Rachellelogram)\ **Post date:** [August 18, 2013, 7:05am UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/9 "2013-08-18T07:05:23Z")
I’ve never bought the two tablespoon theory. I could dump two tablespoons onto a single maxi pad without making a dent in it, and I go through about 20 pads in an average period. And even if there IS just two tablespoons of actual blood coming out, you’ve gotta factor in the uterine lining that’s sloughing off in addition to that. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [August 18, 2013, 9:45am UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/10 "2013-08-18T09:45:07Z")
> [@gigi](#): > > I’ve seen you mention this before; could you explain further? Two tablespoons at a time? Two tablespoons over the whole period? Two tablespoons of blood, not counting other materials? The average amount of menstrual fluid (about 1/2 “blood”, and half water, cellular debris and mucus) in a whole period is about 2 tablespoons, or one ounce. I know, it sounds unbelievable that in all those red pads, there’s only an ounce of fluid, but that number is an average obtained by weighing many women’s pads or using menstrual cups to collect and measure the fluid. There is quite a range, however. Anything less than 80mL, or 5.4 tablespoons, is considered normal. More than 80mL is considered Menorrhagia, or excessive menstrual bleeding. > [@](#): > > Menstrual blood could be more correctly referred to as “menstrual fluid,” because it contains several components in addition to blood. Uterine tissue, vaginal discharge and cervical mucus all appear in various amounts in menstrual blood, so it is important to consider that losing a tablespoon of blood during your period is not the same as losing a tablespoon of blood from a wound. > > The average amount of menstrual fluid lost during a period is about 35 milliliters, or about 2.4 tablespoons. Amounts between 10 and 80 milliliters, or 1 and 6 tablespoons, are considered normal, with nine out of 10 women having a flow that falls within this range. Typically, the majority of this blood is lost within the first three days of your period. [http://www.life123.com/health/womens-health/menstrual-cycle/blood-loss-during-period.shtml](http://www.life123.com/health/womens-health/menstrual-cycle/blood-loss-during-period.shtml) ---
**Author:** ![gigi](https://avatars.discourse-cdn.com/v4/letter/g/a587f6/32.png) [@gigi](https://boards.straightdope.com/u/gigi)\ **Post date:** [August 18, 2013, 5:08pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/11 "2013-08-18T17:08:35Z")
OK, thanks. I’ve pulled out tampons with at least a tablespoon of the jelly-like stuff behind it, at least a few times on the heaviest day. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [August 18, 2013, 5:25pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/12 "2013-08-18T17:25:33Z")
> [@gigi](#): > > OK, thanks. I’ve pulled out tampons with at least a tablespoon of the jelly-like stuff behind it, at least a few times on the heaviest day. Yep, me too. But for every heavy bleeder like you and I, there’s some bitch out there who spots for 2 days and doesn’t need more than a panty liner. 😃 (And, more to the point of the question: even 80mL of fluid isn’t a whole lot when compared to the capacity of the bladder.) ---
**Author:** ![Broomstick](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/broomstick/32/246_2.png) [@Broomstick](https://boards.straightdope.com/u/Broomstick)\ **Post date:** [August 18, 2013, 5:31pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/13 "2013-08-18T17:31:57Z")
> [@gigi](#): > > OK, thanks. I’ve pulled out tampons with at least a tablespoon of the jelly-like stuff behind it, at least a few times on the heaviest day. Yeah, and then some wag will say “but it’s not ALL blood!”. Well, no, it’s not _all_ blood but it sure looks like it, what with the ability of blood to make things, well, blood colored. ---
**Author:** ![Motorgirl](https://avatars.discourse-cdn.com/v4/letter/m/e36b37/32.png) [@Motorgirl](https://boards.straightdope.com/u/Motorgirl)\ **Post date:** [August 18, 2013, 5:34pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/14 "2013-08-18T17:34:09Z")
> [@WhyNot](#): > > Yep, me too. But for every heavy bleeder like you and I, there’s some bitch out there who spots for 2 days and doesn’t need more than a panty liner. 😃 Sorry about that. ☹ I produce less than a teaspoon a month, and haven’t bought anything but panty liners since I got rid of my copper IUD - about 10 years now. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [August 18, 2013, 5:45pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/15 "2013-08-18T17:45:06Z")
> [@Motorgirl](#): > > Sorry about that. ☹ I produce less than a teaspoon a month, and haven’t bought anything but panty liners since I got rid of my copper IUD - about 10 years now. That’s okay, we’ll let you live. If you bring us monthly offerings of chocolate and ibuprofen. 😉 ---
**Author:** ![gigi](https://avatars.discourse-cdn.com/v4/letter/g/a587f6/32.png) [@gigi](https://boards.straightdope.com/u/gigi)\ **Post date:** [August 18, 2013, 6:39pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/16 "2013-08-18T18:39:55Z")
> [@Motorgirl](#): > > Sorry about that. ☹ I produce less than a teaspoon a month, and haven’t bought anything but panty liners since I got rid of my copper IUD - about 10 years now. :: seethes with jealousy 😉 ---
**Author:** ![teela\_brown](https://avatars.discourse-cdn.com/v4/letter/t/d9b06d/32.png) [@teela\_brown](https://boards.straightdope.com/u/teela_brown)\ **Post date:** [August 19, 2013, 7:24pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/17 "2013-08-19T19:24:18Z")
Regarding the OP: when I was a young woman, and before I started taking birth control pills, I always peed like a racehorse on the first day of my period. Got diarrhea on the first day, too. I’d lose about five pounds once all the extra fluid in my system was dumped. ---
**Author:** ![Whitney\_Harper](https://avatars.discourse-cdn.com/v4/letter/w/f0a364/32.png) [@Whitney\_Harper](https://boards.straightdope.com/u/Whitney_Harper)\ **Post date:** [August 19, 2013, 8:19pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/18 "2013-08-19T20:19:24Z")
> [@WhyNot](#): > > Not likely. The menstrual stuff doesn’t take up a whole lot of room. I know it seems like there’s a lot of stuff in there, but it’s really only a couple of tablespoons. Your bladder can hold about 40 tablespoons (500mL, or half a Liter), although most of us feel the urge to go when we’ve got about 20-25 tablespoons in there. So 2 tablespoons in a neighboring organ doesn’t bother the bladder much. I have heard that as well, that only a couple of tablespoons of blood is released during a woman’s period. It’s surprising that only two tablespoons of blood loss could cause anemia, as two tablespoons does not seem like very much. ---
**Author:** ![purplehorseshoe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/purplehorseshoe/32/2996_2.png) [@purplehorseshoe](https://boards.straightdope.com/u/purplehorseshoe)\ **Post date:** [August 19, 2013, 8:28pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/19 "2013-08-19T20:28:23Z")
> [@WhyNot](#): > > Yep, me too. But for every heavy bleeder like you and I, there’s some bitch out there who spots for 2 days and doesn’t need more than a panty liner. :D… Ah, birth control pills, how I wuvs you. It’s like I take them as anti-heavy-period medication and they just happen to have a happy side effect of keeping me from getting knocked up. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [August 19, 2013, 9:32pm UTC](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491/20 "2013-08-19T21:32:10Z")
> [@Springtime\_for\_Spacers](#): > > Back when I still had them day four of my period was peeing day. Huh. I never noticed, but…yeah, me too! (That’d be today…hang on, I gotta go pee. Again…) > [@Whitney\_Harper](#): > > I have heard that as well, that only a couple of tablespoons of blood is released during a woman’s period. It’s surprising that only two tablespoons of blood loss could cause anemia, as two tablespoons does not seem like very much. \*Most \*women don’t get anemic from their periods. I think it’s fair to guess that it’s more likely if you’re on the heavier end of the spectrum AND your diet is low in bioavailable iron. [Next page](https://boards.straightdope.com/t/do-women-urinate-more-when-theyre-on-their-periods/666491.md?page=2)