Endometrial responses in artificial cycles: a prospective study comparing four different oestrogen dosages

• Published in: British journal of obstetrics and gynaecology Vol. 99; no. 9; p. 751
• Main Authors: Li, T C, Cooke, I D, Warren, M A, Goolamallee, M, Graham, R A, Aplin, J D
• Format: Journal Article
• Language: English
• Published: England 01.09.1992
• Subjects: Adult; Endometrium - drug effects; Endometrium - pathology; Estradiol - administration & dosage; Estradiol - analogs & derivatives; Estradiol - blood; Estrogen Replacement Therapy; Estrogens, Conjugated (USP) - administration & dosage; Female; Humans; Primary Ovarian Insufficiency - blood; Primary Ovarian Insufficiency - drug therapy; Primary Ovarian Insufficiency - pathology; Progesterone - administration & dosage; Prospective Studies; Time Factors
• ISSN: 0306-5456
• DOI: 10.1111/j.1471-0528.1992.tb13878.x

To examine the endometrial response to four different regimens of oestrogen. A prospective, randomized cross-over study. Jessop Hospital for Women, Sheffield. Twenty one women with premature ovarian failure divided into three equal groups. Four different regimens of hormone replacement therapy: variable, fixed 1 mg, fixed 2 mg and fixed 4 mg oestrogen dosages. Each woman received the variable dosage regimen in one cycle and crossed over to receive one of the three fixed dose regimens (1 mg, Group 1; 2 mg, Group 2; 4 mg Group 3) in another cycle. Ultrasonographic measurement of endometrial thickness and outpatient endometrial biopsy on day 19 of the artificial cycle; analysis of endometrial specimens by three separate methods: traditional histological criteria, morphometry and immunohistochemistry. The endometrial response was similar in those treated with the variable and the fixed 2 mg or 4 mg dosage regimens. The response was suboptimal in those treated with the fixed 1 mg dosage regimen. Normal endometrial development requires adequate priming of the endometrium by oestrogen, which may be administered in a sequential, variable dosage fashion, or simply by a fixed daily dosage regimen. However, the minimum daily dose required is likely to be 2 mg of oestradiol valerate. No adverse effect on the endometrium was observed at a daily dose of 4 mg oestradiol valerate, which produced plasma levels of oestradiol above the reference ranges of the natural cycle.