Prostaglandin E-2 in semen will suppress immunity and induce COX-2 over-expression for more prostaglandin E-2 synthesis in the rectum and anus tissue, leading to infection and disease; while in the vagina, prostaglandin E-2 suppresses natural vaginal antibiotic for sperms to survive and to swim into the uterus, but rarely induces COX-2 expression unless there is an excessive vaginal abrasion or the woman is under the influence of birth control, medication or street drugs. The vaginal tissue is less sensitive to prostaglandin E-2 than the anal/rectal tissue in igniting a chain reaction of the COX-2 expression.
In light cases, anal sex can cause bowel movement incontinence due to the nervous disorder and abrasion where prostaglandin E-2 plays its role, while in severe causes, it will result in infection (HIV is an typical example).

She enjoyed double-penetration sexual orgasm by her husband's and dog's penis. Please be aware of  anal-sex induced Problems.
==> http://www.actionlove.com/cases/case14308.htm   

Causes and Solution for Interstitial Cystitis, Levator Ani Syndrome or pelvic and rectal pains or spasms.
http://www.actionlove.com/cases/case15422.htm
He said ' I have been using your products for 10 years now and still benefit greatly. Lately I take moodmax, dopafibra, and 5htp. This combo is really ideal, the 5htp seems to be the key. My wife and I have a great sex life. ' On anal sex and stimulation
==> http://www.actionlove.com/cases/case16662.htm
Anal Sex caused her bleeding for no sexual orgasm - beware of infection and diseases. ==> http://www.actionlove.com/cases/case13211.htm   
Drunk (raped) anal sex caused her rectum pains and bleeding for no more sexual orgasm
==> http://www.actionlove.com/cases/case13817.htm   
again, Anal Sex causes her bowel control incontinence for no sexual orgasm
==> http://www.actionlove.com/cases/case11915.htm   
Anal Sex causes her bowel control incontinence for no sexual orgasm
==> http://www.actionlove.com/cases/case11749.htm 
Anal sex can induce bowel incontinence and cause tissue abrasion - requires a lot of lubrication and protection.
==> http://www.actionlove.com/cases/case10979.htm  
Child Abuse, Anal Sex and Over-Masturbation result in urinary / bowel incontinency and sexual exhaustion for no sexual orgasm.
http://www.actionlove.com/cases/case9980.htm