Ultrasonographic endometrial monitoring during continuous-sequential hormonal replacement therapy regimen in postmenopausal women

Objective: To evaluate the endometrial thickness in different periods of a continuous-sequential HRT regimen and to correlate the ultrasonographic fin dings with the histological patterns. Methods: The study was structured in two phases. In the 1st phase, 37 postmenopausal women (group A) treated by at least 6 months with a conventional continuous-sequential hormonal replac ement therapy (cs-HRT) regimen were enrolled. In all patients, the endometr ial thickness was measured at the 7th, 14th. 21st and 25th day of the cycle using transvaginal ultrasonography (TV-USG). In the 2nd phase of the study , other 41 postmenopausal women (group B) were enrolled and treated with th e same sc-HRT regimen. At entry and after six cycles of cs-HRT, an endometr ial biopsy was performed. The endometrial pattern was related with endometr ial thickness. Either the evaluations were performed immediately after prog estogen withdrawal bleeding, as showed by Ist phase results. Results: The r esults of the Ist phase of the study showed a mean endometrial thickness si gnificantly lower at 7th day of the cycle compared to 14th, 21st and 25th d ay (4.3 +/- 1.2 versus 6.6 +/- 2.9. 7.8 +/- 4.2 and 7.4 +/- 4.6 mm +/- SD, respectively). After six cycles of cs-HRT (2nd phase of the study), the mea n endometrial thickness was significantly increased in comparison with basa l values (4.2 +/- 1.5 versus 2.8 +/- 1.2 mm +/- SID: P < 0.05). Endometrial biopsies showed 13 cases (39.4%) of atrophy and 20 cases (60.6%) of prolif erative endometrium. Mean endometrial thickness in case of atrophy was lowe r than in presence of a proliferative endometrium (3.7 +/- 1.2 versus 4.4 /- 1.4 mm +/- SD; not significant). Endometrial thickness was < 4 mm in 16 cases (11 of atrophic and five of proliferative endometrium), between 4 and 5 mm in 15 cases (13 of proliferative and two or atrophic endometrium) and between 5 and 6 min in two cases (either case of proliferative endometrium ). Conclusions: The best timing for monitoring endometrial thickness during cs-HRT regimens is the period immediately after withdrawal bleeding improv ing the reliability of the ultrasonographic exam to identify endometrial pa thologies. (C), 2001 Elsevier Science Ireland Ltd. All rights reserved.