Postmenopausal bleeding (PMB) refers to any uterine bleeding in a menopausal woman (other than the expected cyclic bleeding that occurs in women taking cyclic postmenopausal hormone therapy). It accounts for about 5 percent of office gynecology visits .

All postmenopausal women with unexpected uterine bleeding patients should be evaluated for endometrial carcinoma since this potentially lethal disease will be the cause of bleeding in approximately 10 percent (range 1 to 25 percent, depending upon risk factors) . However, the most common cause of bleeding in these women is atrophy of the vaginal mucosa or endometrium . In the early menopausal years, .endometrial hyperplasia, polyps, and submucosal fibroids are also common etiologies 

INCIDENCE

Vaginal bleeding occurs in approximately 4 to 11 percent of postmenopausal women . The incidence of bleeding appears to correlate with time since menopause, with the likelihood of bleeding decreasing over time. As an example in a study that asked 271 postmenopausal women to complete a daily record, the estimated incidence of bleeding fell from 409/1000 person-years immediately after the first 12 months of amenorrhea following menopause to 42/1000 person-years more than three years after menopause .

ETIOLOGY

Abnormal bleeding noted in the genital area is usually attributed to an intrauterine source, but may actually arise from the cervix, vagina, vulva, or fallopian tubes, or be related to ovarian pathology. The origin of bleeding can also involve nongynecologic sites, such as the urethra, bladder, anus/rectum/bowel, or perineum. Cervical stenosis may inhibit egress of blood from the uterine cavity; hematometra may result.

  • Endometrial atrophy: When the hormone estrogen stops being produced due to menopause, a woman's endometrial lining may start to become thinner. As a result, the lining of the endometrium may be more likely to bleed.
  • Endometrial hyperplasia: This condition causes the uterine lining to become thicker instead of thinner, giving rise to heavy or irregular bleeding. The cause of this condition is most commonly excess estrogen without the hormone progesterone to offset it. Endometrial hyperplasia can sometimes lead to the development of endometrial cancer,
    • Endometrial cancer: This is cancer of the endometrial lining. An estimated 10 percent of postmenopausal women with uterine bleeding experience the bleeding due to endometrial cancer.
    • Polyps: Polyps are growths that can develop on the lining of the uterus. They are usually noncancerous but can cause unusual or heavy bleeding. Polyps can sometimes grow inside the cervical canal. When this occurs, a woman may experience bleeding when she has sex.
     

    Other potential, but less likely, causes of postmenopausal bleeding include:

    • clotting problems
    • infection of the uterine lining, which is known as endometritis
    • trauma to the pelvis
    • bleeding from the urinary tract
    • thyroid disorders

    Hormone medications, such as tamoxifen, may also cause postmenopausal bleeding as a side effect. Many women will experience breakthrough bleeding as a result of taking hormone replacement therapy in the first 6 months.