Aetiology

PATHOPHYSIOLOGY IN MENOPAUSE

• When oestrogen levels decline, the squamous vaginal epithelium becomes thinner and there is a loss of glycogen rich cells and lactobacilli.
• This causes a rise in vaginal pH, allowing vaginal commensal organisms such as E Coli to increase. This can cause new vaginal discharge, odour and urinary infections.
• The urethra can become more prominent and may prolapse, which can facilitate ascending infection.
• Below the vaginal mucosa, the collagen fibres can fuse. This causes reduced vaginal elasticity, which is linked to pain with penetration or use of speculums.
• As the vaginal epithelium becomes thinner, the density of neurones in the vagina increases, which is likely to contribute to symptoms of discomfort.
• This is an intermediate effect, often taking 3 to 5 years or longer to become apparent.

MEDICATION INDUCED

• Medications that lower oestrogen levels such as aromatase inhibitors or GnRH analogues increase risk of genitourinary symptoms.
• Tamoxifen has both oestrogen agonist and antagonist effects on the vaginal epithelium and can cause vaginal dryness and discharge.
• The incidence rate of vaginal dryness with tamoxifen is 8% compared to 18% with aromatase inhibitors.