In premenopausal women, the source of vaginal bleeding after sex is usually the cervix — the narrow, lower end of the uterus. Even with a completely healthy cervix, enough friction or mild trauma during sexual intercourse can cause some bleeding. Inflammation of the cervix or some other abnormality, most of which are harmless, can also result in bleeding. Sometimes, though, vaginal bleeding after sex is a sign of a sexually transmitted infection.

In postmenopausal women, vaginal bleeding after sex may arise from the opening of the bladder (urethral meatus), the outer opening of the vagina (labia) or the uterus, as well as the cervix.

Possible causes of vaginal bleeding after sex include:

  1. Cervical cancer
  2. Cervical ectropion, a condition in which the inner lining of the cervix protrudes through the cervical opening and grows on the vaginal part of the cervix
  3. Cervical polyps, noncancerous (benign) growths on your cervix
  4. Cervicitis (inflammation of the cervix)
  5. Friction during sexual intercourse
  6. Genital sores that result from sexually transmitted infections, such as genital herpes or syphilis
  7. Inadequate lubrication or foreplay
  8. Injury to the uterine lining (endometrium) during intercourse, especially in women taking oral contraceptives
  9. Normal uterine bleeding, if you're just beginning your period or if it has just ended
  10. Trauma from sexual abuse
  11. Vaginal atrophy
  12. Vaginal dryness
  13. Vaginitis

If you're premenopausal and you have vaginal bleeding after sex once in a while, it probably isn't something to get too worried about. Vaginal bleeding after sex could indicate cervical cancer, but if you've had normal results on routine Pap tests, it's more likely that the bleeding results from a noncancerous (benign) condition.

If you're postmenopausal, however, vaginal bleeding of any sort is abnormal and needs to be evaluated to find the cause. After menopause, vaginal atrophy (atrophic vaginitis) or other conditions associated with vaginal dryness are the most likely causes of vaginal bleeding after sex, but it could also be caused by other, more serious conditions.

Causes shown here are commonly associated with this symptom. Work with your doctor or other health care professional for an accurate diagnosis.

Nov. 26, 2014