The relationship between endometriosis and early menopause is complex, as both the disease itself and its common treatments can accelerate the end of a woman’s reproductive years. Endometriosis is a chronic inflammatory condition where tissue similar to the uterine lining grows outside the uterus, most commonly in the pelvic cavity. Menopause is clinically defined as the cessation of menstrual periods for twelve consecutive months, which typically occurs around age 51. For women with endometriosis, the primary concern is the potential for this condition to hasten the decline of the ovarian reserve, the quantity and quality of a woman’s eggs, leading to an earlier onset of menopause.
Defining Premature and Early Menopause
Early Menopause is diagnosed when a woman experiences her final menstrual period between the ages of 40 and 45. This distinction is significant because it is earlier than the average age of natural menopause, which is around 51.
A more severe and earlier condition is Premature Ovarian Insufficiency (POI), which occurs when ovarian function declines before the age of 40. POI affects about one in 100 women under the age of 40.
The diagnosis for both conditions is confirmed by a combination of a lack of menstrual periods and specific hormone levels, such as abnormally high levels of Follicle-Stimulating Hormone (FSH) and low levels of estrogen, demonstrating that the ovaries are no longer responding effectively. It is important to differentiate between natural onset and medically induced menopause. Menopause caused by medical intervention, such as the surgical removal of both ovaries, is termed “induced” or “surgical” menopause.
The Systemic Link: Endometriosis and Ovarian Reserve
Endometriosis itself, separate from any surgical intervention, is linked to a reduced Ovarian Reserve. The presence of endometriotic lesions, particularly ovarian cysts known as endometriomas, creates a chronic inflammatory microenvironment within the pelvis.
This persistent inflammation involves the release of pro-inflammatory substances and oxidative stress that can be toxic to the surrounding ovarian tissue. This toxic environment can directly damage the ovarian follicles, which are the structures that house the eggs, leading to their premature loss.
Studies show that women with endometriosis often have lower levels of Anti-Müllerian Hormone (AMH), a reliable marker for ovarian reserve, even before surgery. The chronic inflammation and oxidative stress can also trigger fibrosis, or scarring, in the ovarian tissue, further compromising its function.
Epidemiological studies support a correlation between a diagnosis of endometriosis and an earlier onset of natural menopause. While the disease does not guarantee early menopause, the systemic and localized damage to the ovaries suggests that endometriosis can inherently shorten the reproductive lifespan by accelerating the depletion of the egg supply.
Iatrogenic Risk: Surgical Intervention and Ovarian Function
A major pathway to premature or early menopause for women with endometriosis is the effect of surgical treatment. The term iatrogenic refers to a condition caused unintentionally by a medical procedure. Surgical intervention for endometriosis, especially the removal of endometriomas, carries a risk of inadvertently reducing the ovarian reserve.
The removal of an endometrioma, often performed through a procedure called ovarian cystectomy, requires the surgeon to strip the cyst wall from the surrounding ovarian tissue. Unlike other benign cysts, endometriomas often adhere tightly to the ovarian cortex, making it difficult to separate the cyst without removing healthy ovarian tissue and follicles along with it.
Research suggests that up to 54% of excised tissue in endometrioma cystectomies may be healthy ovarian tissue. Damage can also occur through thermal injury from electrosurgical tools used to stop bleeding during the procedure.
The effect is particularly pronounced in cases of bilateral endometriomas, where surgery is performed on both ovaries, significantly increasing the risk of developing premature ovarian failure. The complete removal of one or both ovaries, called an oophorectomy, is sometimes necessary to treat extensive disease, which immediately induces surgical menopause.
Monitoring and Proactive Management
For women diagnosed with endometriosis, proactive management and monitoring are important to mitigate the risk of early ovarian decline. The primary tool for estimating ovarian reserve is the Anti-Müllerian Hormone (AMH) test. Regular AMH testing, especially before and after any surgery, can provide an estimate of the remaining egg supply and help predict the approximate timing of menopause.
For younger patients with severe disease, fertility preservation strategies should be discussed as a priority. Options such as oocyte (egg) or embryo cryopreservation (freezing) can be pursued before potential ovarian damage from either the disease progression or necessary surgery occurs.
Should a woman with endometriosis experience premature or early menopause, symptom management typically involves Hormone Replacement Therapy (HRT). Because endometriosis is an estrogen-dependent condition, the standard recommendation is to use a combined HRT regimen (containing both estrogen and progestogen) rather than estrogen alone.