2. INTRODUCTION
• Benign tumours (leiomyomata) of uterine smooth muscle
• Common – 25% of women in a lifetime
• The most common uterine tumor
• Occurring in about 30% of women above the age of 30 years.
• Occurs up to 75% of hysterectomy specimens
• Symptomatic in 1/3 of cases
• More common in the obese
• Less common in smokers
3. • Age:
30-40 years.
Rare before 30 or after 40 years
• Parity:
Common in nulliparas, patients with low parity.
It is rare in multiparas.
• Race:
3-9 times more common in negroids.
• Family history:
Usually positive.
• Hyper-estrenemia:
Estrogen receptors (ER) more than the surrounding myometrium but less than those in the
endometrium
• Common in low parity.
• Atrophies and shrinks after menopause.
• Common association with other hyper-estrenic conditions as endometriosis, endometrial
hyperplasia and endometrial carcinoma.
4. ETIOLOGY
• Genetic changes: Many fibroids contain changes in genes that
differ from those in normal uterine muscle cells.
• Hormones: Estrogen and progesterone, two hormones that
stimulate development of the uterine lining during each
menstrual cycle in preparation for pregnancy, appear to
promote the growth of fibroids. Fibroids contain more estrogen
and progesterone receptors than normal uterine muscle cells
do. Fibroids tend to shrink after menopause due to a decrease
in hormone production.
• Other growth factors: Substances that help the body maintain
tissues, such as insulin-like growth factor, may affect fibroid