Hormone replacement therapy. ACOG technical bulletin number 166--April 1992 (replaces no. 93, June 1986)

All patients receiving hormone replacement therapy should be evaluated annually. During these evaluations, breast and pelvic examinations should be performed and a Pap smear taken, and attention should be directed to cholesterol, blood pressure, and the effectiveness of treatment. In women given adequate progestins (medroxyprogesterone acetate, 10 mg each day for 12 days a month), endometrial biopsy should be reserved for women with clinical problems such as excessive or prolonged bleeding. In women taking no progestins, pretreatment and yearly biopsies are required. In addition, annual mammograms should be obtained on women over the age of 50. Hormone replacement therapy, although not suited to all patients, can confer health benefits, enhance quality of life, and prolong life expectancy (46).

Published by International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics, 1993. The guideline itself is at the source linked here.

pubmed.ncbi.nlm.nih.gov/8099041/