Cochrane Systematic Reviews 

Hormone replacement therapy in postmenopausal women: endometrial hyperplasia and irregular bleeding 

Furness S, Roberts H, Marjoribanks J, Lethaby A. Hormone therapy in postmenopausal women and risk of endometrial hyperplasia. Cochrane Database of Systematic Reviews 2012, Issue 8. Art. No.: CD000402. DOI: 10.1002/14651858.CD000402.pub4

http://www.cochrane.org/reviews/en/ab000402.html for abstract.  

Assessed as up to date: 27 January 2012