Biologically important natural estrogens and progestins include estradiol, estrone, estriol, and progesterone. Estradiol-17 is the most potent estrogen that is found naturally in women. Estrone is one-tenth as biologically active as estradiol, and estriol is the weakest of the three. Estriol is synthesized by the placenta and is excreted at high levels in the urine of pregnant women. Progestero...

OBJECTIVE To estimate the association of the estrogen and progestin potency of combined oral contraceptive pills (OCPs) with epithelial ovarian carcinoma risk. METHODS This population-based case-control study included 745 women with incident, histologically confirmed epithelial ovarian carcinoma and 943 controls, matched on age and ethnicity. Data were collected using a standard questionnaire...

OBJECTIVE To report our 15-year institutional experience of fertility-sparing treatment in young patients with early endometrial cancer (EC) treated by combined hysteroscopic resection and progestin therapy. METHODS Twenty-eight patients (stage IA, G1 and 2 endometrioid EC) wishing to preserve their fertility were enrolled into this prospective study. Hysteroscopic resection was used to resec...

OBJECTIVE To evaluate the influence of estrogen therapy and estrogen-progestin therapy on homocysteine and C-reactive protein levels in postmenopausal women. METHODS In total, 99 postmenopausal women were included in this double-blind, randomized clinical trial and divided into three groups: Group A used estrogen therapy alone (2.0 mg of 17β-estradiol), Group B received estrogen-progestin the...

Concentrations of cytosol estrogen (ERC) and cytosol progestin (PRC) receptors were assayed in malignant tissue specimens of 230 patients with endometrial cancer, and those of nuclear estrogen and nuclear progestin receptors, and 17 beta-hydroxysteroid dehydrogenase activities in about 100 specimens. Endometrial cancer was at an early stage in 205 and advanced in 25 patients. As a supplement to...

BACKGROUND Recent studies offer conflicting data on risks of ovarian cancer in users of menopausal hormone therapy. Some findings of increased risks associated with unopposed estrogen use are based on older studies of women with intact uteri, and small sample size and incomplete exposure information have limited the data on estrogen plus progestin associations. METHODS The National Institutes...

The molecular basis of the growth-inhibitory effects of progestins or antiestrogens in human breast cancer has not been fully elucidated. Both direct actions and indirect actions, where the growth inhibition results from modulation of the production of, and/or the response to, growth factors, have been proposed. In this study the ability of some growth factors to modulate progestin-induced inhi...

The aim of this study was to determine if progesterone modulates object and spatial memory consolidation in young ovariectomized C57BL/6 mice. Object memory was tested in an object recognition task using 24- and 48-h delays. Spatial memory was tested in a 2-day version of the Morris water maze in which retention was tested 24 or 48 h after training. Immediately after training in each task, mice...

The effects of immunosuppressants and inhibitors of specific calcium/calmodulin kinase (CaMK) of types II and IV on progestin/glucocorticosteroid-induced transcription were studied in two human stably transfected breast cancer T47D cell lines. The lines contain the chloramphenicol acetyl transferase (CAT) gene under control either of the mouse mammary tumor virus promoter (T47D-MMTV-CAT), or th...

CONTEXT In the Women's Health Initiative trial of estrogen-plus-progestin therapy, women assigned to active treatment had fewer fractures. OBJECTIVE To test the hypothesis that the relative risk reduction of estrogen plus progestin on fractures differs according to risk factors for fractures. DESIGN, SETTING, AND PARTICIPANTS Randomized controlled trial (September 1993-July 2002) in which 1...