Postmenopausal Bleeding: An Evidence-Based Clinical Overview

Introduction

Menopause is the natural end of female reproductive function and is often associated with both physiological and psychosocial changes. As ovarian follicular reserves become depleted and ovarian function ceases, estradiol production declines, leading to estrogen deficiency and the development of postmenopausal syndrome. Although reproductive function has ended, it remains important for women to care for their health during menopause as responsibly as they did during their reproductive years.

The Society of Obstetricians and Gynaecologists of Canada (SOGC) and the Canadian Menopause Society encourage postmenopausal women to maintain a healthy diet, exercise regularly, reduce tobacco and alcohol consumption, and adopt effective stress-management and relaxation strategies [1]. Sexual activity, with or without a partner, has beneficial effects on pelvic blood circulation, helps maintain vaginal tissue elasticity, and may reduce urogenital symptoms after menopause [2].

One of the most common reasons postmenopausal women consult a gynecologist is genital tract bleeding. Postmenopausal bleeding (PMB) is defined as any vaginal bleeding occurring after menopause, except for predictable withdrawal bleeding in women receiving cyclic menopausal hormone therapy (MHT) [3]. Approximately 4%–11% of women experience PMB after menopause, and its incidence decreases as the time since menopause increases [4]. Although PMB most commonly originates from the uterine cavity, bleeding may also arise from the cervix, vagina, vulva, or from non-gynecological sources such as the urethra, bladder, anus, or perineum. Bleeding may also be associated with anticoagulant therapy, soy-based dietary supplements, or previous pelvic radiotherapy [5].

Etiology

In most cases, postmenopausal bleeding is light and self-limiting. However, every woman presenting with PMB should undergo a thorough evaluation because endometrial cancer accounts for approximately 10% of PMB cases (reported range, 1%–25%) [6]. The most common cause of PMB is endometrial and vaginal atrophy [7]. Endometrial polyps, endometrial hyperplasia, and uterine leiomyomas may also cause PMB, particularly during the early postmenopausal period [8].

Endometrial cancer is a malignant tumor arising from the endometrium that invades the myometrium and cervix before eventually spreading beyond the uterus. A large meta-analysis found that approximately 9% of women presenting with PMB are diagnosed with endometrial cancer [9]. The earliest and most important symptoms include vaginal bleeding and blood-stained watery discharge, allowing diagnosis at a potentially curable stage. The likelihood of endometrial cancer increases the longer the interval between menopause and the onset of bleeding. Age over 55 years, recurrent episodes of postmenopausal bleeding, and heavy bleeding requiring the use of more than five sanitary pads per day are also associated with an increased risk of endometrial cancer [10].

A simulation study found that postmenopausal women over 70 years of age with diabetes had an 87% probability of developing endometrial hyperplasia or carcinoma, compared with only 3% among women without these characteristics [11].

Clinically, endometrial hyperplasia may present with PMB. Because estrogen levels naturally decline after menopause, the diagnosis of endometrial hyperplasia should prompt investigation for possible sources of increased estrogen exposure. Potential causes include endogenous estrogen production by ovarian or adrenal tumors or exogenous estrogen exposure through menopausal hormone therapy (MHT) or tamoxifen treatment. Women with obesity also have higher estrogen levels because androstenedione is converted to estrone within adipose tissue.

Uterine sarcomas are malignant tumors arising from connective tissue or smooth muscle and account for approximately 3%–5% of all uterine malignancies. They may present with PMB. These tumors are difficult to diagnose because they often resemble benign uterine leiomyomas, and endometrial histology may be normal. Therefore, when PMB occurs in a woman with a uterine fibroid identified by ultrasound, uterine sarcoma should be considered in the differential diagnosis [12].

A common cause of PMB during the perimenopausal or early postmenopausal period is endometrial polyps. These benign endometrial overgrowths may develop or enlarge in women receiving estrogen therapy or tamoxifen.

Cervical and vaginal cancers often present with vaginal bleeding, particularly postcoital bleeding or blood-stained vaginal discharge. As the tumor progresses, bleeding typically becomes heavier and may be accompanied by lower abdominal pain and fever. The introduction of HPV vaccination has reduced the incidence of cervical cancer worldwide. Unfortunately, cervical cancer remains one of the most common malignancies among women in Lithuania.

During menopause, declining estrogen levels lead to atrophy of the vaginal epithelium and endometrium, the most common cause of PMB. Thinning of the mucosa and reduced lubrication increase friction within the genital tract, causing microscopic epithelial erosions and chronic inflammation. Clinically, these changes present as light bleeding or spotting [13].

The most common signs of atrophic vulvovaginitis are pale, dry, smooth, and fragile vaginal mucosa.

Vaginal atrophy is characterized by the loss of normal vaginal rugae. It may present with erythema, petechiae, and blood vessels visible through the thinned vaginal epithelium. In addition to bleeding, women commonly complain of vaginal dryness, irritation, burning, pruritus, urinary symptoms (including urinary urgency, dysuria, and urinary incontinence), recurrent urinary tract infections, and dyspareunia. Water-based lubricants are effective for symptom relief, as is local vaginal estrogen therapy.

Dr. Aistė Milaknytė

Faculty of Medicine, Vilnius University