Endometrial Hyperplasia Without Atypia

Endometrial hyperplasia without atypia is a benign thickening of the endometrium with crowded glands of varied size and shape, no nuclear atypia, and a low risk of progression to cancer.

• It results from prolonged oestrogen stimulation without progesterone.
• It is common in obese and postmenopausal women and in women with chronic anovulation.
• Treatment is progestogen therapy with follow-up biopsy.

Postmenopausal bleeding, heavy menstrual bleeding, intermenstrual bleeding or oligomenorrhoea followed by heavy bleeding; some women are asymptomatic.

• Examination is often normal.
• Differential diagnosis: atypical hyperplasia, endometrial cancer, endometrial polyp, atrophic endometritis, submucosal fibroid, ovarian oestrogen-producing tumour.
• Complications: anaemia, progression to atypical hyperplasia or cancer, relapse after treatment.

Diagnosis is by endometrial biopsy, supported by ultrasound.

• Transvaginal ultrasound showing a thickened endometrium (above 4 mm after menopause).
• Pipelle sampling or hysteroscopic biopsy with histology.
• Pelvic examination; cervical screening; full blood count; fasting glucose.
• Pelvic imaging for ovarian tumour when oestrogen excess is unexplained.

Give progestogen therapy with weight loss, and repeat biopsy to confirm regression.

• Supportive: weight loss; stop or change unopposed oestrogen therapy; manage diabetes and hypertension.
• Pharmacological: levonorgestrel 52 mg intrauterine system for at least 6 months (first choice). Oral options: medroxyprogesterone acetate 10 mg oral daily for 6 months, or norethisterone 5 mg oral 12-hourly for 6 months. Heavy bleeding: tranexamic acid 1 g oral 8-hourly for up to 4 days (maximum 4 g in 24 hours). Anaemia: ferrous sulphate 200 mg oral 8-hourly, continued for 3 months after haemoglobin normalises.
• Procedures: hysteroscopy with biopsy of focal lesions; hysterectomy with bilateral salpingectomy for progression to atypia, persistent hyperplasia after 12 months of treatment, or when the woman prefers definitive treatment.
• Special groups: in postmenopausal women on hormone therapy, add a progestogen if the uterus is present and review the oestrogen dose. In women with obesity, consider referral for weight management. In liver impairment avoid oral progestogens and use the intrauterine system.
• Red flags: atypia on repeat biopsy, endometrial thickness above 10 mm after menopause, recurrent bleeding, weight loss.
• Follow-up: biopsy at 6 months; repeat every 6 months until two negative biopsies; yearly review if risk factors persist.