Transvaginal sonography of the endometrium in a representative sample of postmenopausal women

The aim of this study was to assess endometrial thickness using transvaginal sonography in a representative sample of postmenopausal women and to evaluate whether the technique can be used for screening of endometrial cancer. A random sample (n =1000) of the total population of women aged 45-80 years resident in the city of Goteborg in 1993 was invited to attend for transvaginal sonography. The only exclusion criterion was hysterectomy. Transvaginal sonography was performed in 827 women. An endometrium of less than or equal to 4 mm was not investigated further. Women with an endometrium of 5-7mm and non-mensurable cases were re-assessed 1 year later, and women with an endometrial thickness of greater than or equal to 8 mm were investigated directly with hysteroscopy and/or dilatation and curettage. A total of 559 women were postmenopausal and 183 were taking some form of hormonal substitution (33%). One case of endometrial cancer (endometrial thickness 13 mm), 23 cases of polyps without atypia (endometrial thickness 8-18 mml and no cases of endometrial hyperplasia were diagnosed. Endometrial thicknesses were as follows (mean +/- SEM; respectively grouped as less than or equal to 4 mm, 5-7 mm and greater than or equal to 8 mm): total population of postmenopausal women (3.4 +/- 0.1 mm, 82%, 13% and 6%); postmenopausal women without estrogens 33.0 +/- 0.1 mm, 90%, 7% and 3%); postmenopausal women on medium-potency estrogens + gestagen (5.1 +/- 0.3 mm, 49%, 40% and 11%) and women with low-potency estrogens only (3.6 +/- 0.3 mm, 85%, 6% and 9%). The prevalence of endometrial cancer was 0.2% and for benign polyps 3.2% in this representative sample of postmenopausal women. Our results do not support generalized endometrial screening with transvaginal sonography.