Postmenopausal hormone replacement therapy and risk of endometrial hyperplasia

The addition of oral progestogens administered either sequentially or continuously is associated with reduced rates of endometrial hyperplasia and improved adherence to therapy compared to oestrogen alone for treatment of menopausal symptoms.

A Cochrane review included 46 studies with over 38 000 subjects. Unopposed estrogen was associated with increased risk of endometrial hyperplasia at all doses, and durations of therapy between one and three years. For women with a uterus the risk of endometrial hyperplasia with hormone therapy comprising low dose estrogen continuously combined with a minimum of 1 mg norethisterone acetate (NETA) or 1.5 mg medroxyprogesterone acetate (MPA) was not significantly different from placebo (1 mg NETA: OR 0.04 (0 to 2.8); 1.5 mg MPA: no hyperplasia events).

In six trials, rates of endometrial hyperplasia after 1 year of therapy were significantly higher for the group receiving low or moderate dose unopposed estrogen therapy, compared with the group receiving continuous combined low or moderate dose estrogen + progestogen treatment, for all of the 13 regimens compared, with odds ratios for the individual comparisons ranging between 3.8 and 9.4. There were statistically significant differences in the odds of developing endometrial hyperplasia at one year between the groups taking unopposed estrogen and the groups taking sequential estrogen plus progestogen in all of the regimens compared, favouring the sequential group (4 studies).

Ədəbiyyat

1. Furness S, Roberts H, Marjoribanks J, Lethaby A, Hickey M, Farquhar C. Hormone therapy in postmenopausal women and risk of endometrial hyperplasia. Cochrane Database Syst Rev 2009;(2):CD000402 (Last assessed as up-to-date: 27 January 2012).