Q. I know that many are going to find this gross, but I know that it happens to more than just me and I was curious as to why this is happening. When I have a strong orgasm, I tend to defecate a little. This usually only happens when I masturbate - I guess because I get a bigger orgasm when masturbating vs. being with my husband. I do go to the bathroom beforehand but doesn't help. My husband loves to see me masturbate but I feel uncomfortable and have to hold back because I don't want to gross him out. Do you know why this happens and if there is a way to avoid it?
A. Let’s talk Anatomy! The lower third of the vagina shares common walls with both the urethra (the tube that connects our bladder to our genitals to release urine) and with the rectum (the final portion of our large intestine that removes solid waste from our bodies). The vagina and rectum actually support one another with this shared wall of smooth muscle and collagen. These walls are highly vascularized, meaning that they are filled with blood vessels, and teeming with sensitive nerve endings. For its entire length (from top to bottom), where the vagina does not share a common wall with the rectum, it is still resting up against the rectal wall. Knowing this may make it less of a surprise that sexual intercourse can therefore easily stimulate both the vagina and the rectum, providing us with a perfectly reasonable explanation as to why you experience defecation during your orgasm.
Next let’s talk physiology! During an Orgasm, a woman experiences a number of physical effects. The clitoris is stimulated and becomes engorged with blood, similar to a male erection. She experiences an elevation in rate of respiration (breathing), blood pressure, and heart rate. Tension builds in her entire pelvic region due to rhythmic muscular contractions, especially in the vagina, rectum, uterus and pelvic floor. This tension subsides with the relaxation of smooth muscle in these areas. Although not all that common, it is also possible to receive an orgasm from anal penetration because of these muscular contractions, without vaginal stimulation. The urge to defecate comes from rhythmic muscle contractions that function to move feces from the digestive tract, out via the rectum. This is normally a combination of voluntary and involuntary forces, but what you may have experienced is an involuntary relaxation of the two sphincters (internal anal sphincter and external anal sphincter), causing you to leak a little feces against your will.
Empty your bowels before you have sex the next time, and try to take note of the position that it occurs in, if it happens again. It may also help to perform an Enema to clean out the lower area – especially to ease your self-consciousness when with your husband. Hopefully a combination of emptying your bowels prior to sex and avoiding positions that may put pressure on the rectum via the posterior wall of your vagina will help. Good luck!