Vaginal bleeding while defecating during menstruation

This topic is posted here in response to a lady called Laura, who posted on the Women's Quest Forums. I was unable to fit my whole response in the space available, so I have responded here, thinking that our readers may also be interested to know about the relevant pelvic anatomy.

Hi Laura, it is now quite a while since you posted. I am hoping that the bleed has now finished and that you are no longer worried about it. However, in the interests of understanding this bleed, do you mean that you were having an unexpected period and that it was not like a normal period? Irregular periods can be caused by many factors. I am wondering how old you are, ie is this to do with the perimenopause, or are you at an earlier stage of your reproductive life? When you say that you are bleeding through your vagina when you defecate, do you mean that this is the first time it has happened?

When we defecate all the contents of our large intestine moves along the intestinal tract towards the rectum as the rectum empties. If there are harder, drier bits of stool in there, they are likely to push against your uterus on the way through. This maybe uncomfortable for you, and it might make your uterus contract in response, squeezing menstrual fluid out into your vagina while you are defecating. I used to get a bit constipated just before a bleed and have this happen sometimes. It was a phenomenon that passed after the first couple of days of a bleed.

The uterus kind of pokes out into the abdominal cavity because it is inside a fold of peritoneum on the abdominal side of the pelvic inlet. The uterus is a pelvic organ, but only the cervix is inside the pelvic cavity. The body of the uterus, which grows upwards and outwards during pregnancy, is in the 'abdominal space'.

Sorry, this is a bit hard to explain. I have not been able to find an anatomical term for the membrane that separates the abdominal cavity from the pelvic cavity. It is simply described as peritoneum, and it is quite soft and floppy. It is not muscular like the diaphragm that separates the thoracic from the abdominal cavity. You can see an illustration of it here, https://www.facebook.com/photo.php?fbid=3669023163691&set=o.372777748545... . It is the red line in the left hand and centre illustrations. These illustrations show how the pelvic organs can move around in the pelvic cavity. The bladder, uterus and rectum are all loosely tethered to each other by fascia, or connective tissue, which is like 3D spider web. When one distends the others move to accommodate that distension.

Sometimes the uterus becomes tipped or retroverted, and sinks down backwards into the Pouch of Douglas, which is between the rectum and vagina. In this position, it is not in its normal place, so may be more prone to pressure from intestines or squashed against the sacrum (ouch!). My uterus used to be retroverted before menopause, but it quite suddenly righted itself and anteverted, so it was sitting on top of my bladder where it should have been all along. My last few years of periods suddenly became less traumatic, with less flooding and cramping. I think my uterus was at last happy! :-)

Here is quite a good page about retroverted uterus. There is an illustration about 3/4 of the way down the page of anteverted and retroverted uterus. http://www.primehealthchannel.com/retroverted-tilted-tipped-uterus-sympt... .

Our posture largely determines the positions of our pelvic organs relative to each other. When our pelvic inlet is more vertical (anteverted pelvis) the pelvic organs can 'rotate' forwards. This gives the retroverted uterus the opportunity to come out from under your sacrum, straighten up and and flop forwards onto your bladder and lower abdominal wall, which it may do in time, like mine did.

You can explore Whole Woman posture here at this site. See the FAQs and the videos in the Resources tab. I hope this gives you some idea of how heavier bleeding during defecation can be harmless, but can also teach you something about your anatomy.

Of course, if you this explanation does not explain your bleeding a visit to the doctor may yield a medical answer. This is a community Forum, and we are not medically qualified. We have just figured it out ourselves with the help of Christine Kent, owner of this site.

Louise