Perimenopause vs Fibroids: Are Your Symptoms Hormonal or Structural?
Heavy periods and pelvic pressure could be perimenopause or uterine fibroids. Here is how to tell them apart and what treatment each requires.
Two Conditions, Overlapping Symptoms
Uterine fibroids and perimenopause are two of the most common gynaecological issues affecting women in their 40s and early 50s. Fibroids are non-cancerous growths in or on the uterus. Perimenopause is the hormonal transition leading up to menopause. Both can produce heavy or irregular bleeding, pelvic discomfort, and fatigue. Because they affect the same age group and share so many surface-level features, one is frequently assumed to be the other. However, the underlying causes and treatment options are entirely different, so accurate identification matters.
What Fibroids Are and Why They Develop
Fibroids, also called leiomyomas or myomas, are smooth muscle tumours in the uterus. They are not cancerous and rarely become so. Their exact cause is not fully understood, but oestrogen and progesterone drive their growth, which is why they are most common during the reproductive years and tend to shrink after menopause. Fibroids range from the size of a pea to, in rare cases, the size of a grapefruit. Some women have multiple fibroids of varying sizes. Location matters: fibroids inside the uterine cavity (submucosal) tend to cause the most bleeding, while those embedded in the wall (intramural) may cause bulk symptoms, and those on the outside of the uterus (subserosal) may cause pressure on nearby organs.
Symptoms More Specific to Fibroids
Fibroids can cause a noticeable feeling of fullness or heaviness in the lower abdomen that persists throughout the cycle, not just during menstruation. Urinary frequency or difficulty emptying the bladder may occur if a fibroid presses on the bladder. Constipation or a feeling of rectal pressure can develop if a subserosal fibroid pushes against the bowel. Pain during sex that is deep and central rather than vaginal is another pointer. Some women can feel a hard lump in the lower abdomen. If bleeding is so heavy it requires changing protection every hour or passing large clots, fibroids are a more likely explanation than perimenopause alone.
Symptoms More Specific to Perimenopause
Hot flashes, night sweats, and sleep disturbances are strongly associated with perimenopause and are not caused by fibroids. Vaginal dryness, reduced libido, and discomfort during sex from dryness rather than depth are oestrogen-related perimenopausal changes. Mood swings, anxiety, brain fog, and a generalised feeling of hormonal instability point to the hypothalamic-pituitary-ovarian axis rather than a structural uterine issue. Progressive changes in cycle length, particularly cycles becoming longer over time before eventually stopping, are a perimenopausal pattern.
Diagnosis: What to Expect
A pelvic ultrasound identifies fibroids accurately and can measure their size and location. A GP may also perform a pelvic examination, and in some cases an MRI provides more detail. Blood tests including FSH, LH, and estradiol give a hormonal picture useful for assessing perimenopausal status. Full blood count checks for anaemia. Endometrial biopsy may be recommended if bleeding is particularly heavy or irregular to rule out endometrial pathology. It is worth noting that perimenopause and fibroids frequently coexist. Having one does not exclude the other, and treatment may need to address both.
Treatment Approaches and What Guides Them
Perimenopause management focuses on symptom relief through lifestyle changes, and in many cases hormone replacement therapy. Fibroids are managed based on size, location, and severity of symptoms. Small fibroids with minimal impact may need no treatment. Options for symptomatic fibroids include the hormonal coil (Mirena IUS), tranexamic acid to reduce bleeding, surgical options such as myomectomy or hysterectomy, and uterine fibroid embolisation. HRT for perimenopause does not shrink fibroids and may cause some fibroid growth, so the decision to start HRT in a woman with fibroids warrants a conversation with a gynaecologist about monitoring. Reaching an accurate diagnosis is the first step toward choosing the right path.
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