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Updated: Aug 17, 2026

Performing Vaginal Lavage, Crystal Violet Staining, and Vaginal Cytological Evaluation for Mouse Estrous Cycle Staging Identification
Published on: September 15, 2012
[Comparative sonographic and endocrine studies of gonadotropin-stimulated menstrual cycles]
Abstract:
In 18 cycles of 16 patients the morphological changes following stimulation by human gonadotrophin were followed by ultra-sonography and radio-immunoassays of 17 beta-estradiol and progesterone (HMG). In 9 of 18 cycles hyperstimulation with more than 3 follicles on the day of chorionic gonadotrophin administration were found. When the human menopausal gonadotrophin treatment (HCG) results in the maturation of more than 10 follicles per ovary the estradiol level reaches more than 2000 pg/ml. In 4 of 8 cycles the administration of HCG triggered the hyperstimulation syndrome. In 5 of 18 cycles pregnancy was induced after a follicle of at least 17 mm diameter was found independant of the number and size of concommitant follicles. Because of the high incidence of HMG hyperstimulation ultra-sonographic prediction of a multiple pregnancy is of no practical value. In 6 of 10 treated cycles without success the deformation or unclear margins of the predominant follicle suggested an insufficient stimulation with HMG. For the monitoring of follicular maturation ultrasonography is superior to estradiol determination since only a large number of follicles showed correlation to elevated estradiol levels.
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