OBJECTIVE To elucidate the physiologic mechanism responsible for the supraphysiologic gonadotropin release from the pituitary induced by gonadotropin-releasing hormone (GnRH) agonist in female rats primed with GnRH antagonist. DESIGN Controlled experimental intervention. SETTING Government research facility. ANIMAL(S) Forty 8-week-old Sprague-Dawley rats. INTERVENTION(S) Forty oophorect...

Gonadotropin-releasing hormone (GnRH) agonist has been used in the treatment of a wide variety of sex-hormone-related diseases, as the administration of GnRH agonist can alter the secretion of gonadotropin and sex hormones. Recently, we found that the long-acting GnRH agonist aggravated hyperthyroidism and induced painless thyroiditis. This is the first report to demonstrate the association of ...

PURPOSE This study aimed to determine the oncologic efficacy of gonadotropin-releasing hormone (GnRH) agonist treatment concurrent with chemotherapy in a neoadjuvant setting. METHODS A retrospective analysis was performed on 332 cases of invasive breast cancer in patients who were <40 years old at diagnosis and received GnRH agonists concurrent with neoadjuvant chemotherapy (GnRH agonist grou...

BACKGROUND GnRH analogs (both agonist and antagonist) have been extensively used for clinical applications, following the discovery of its direct effects on ovary. With regard to the direct actions of GnRH agonist on ovary, conflicting data are reported. The mechanism through which GnRH agonist affect gonadal functions is still obscure. The aim of present study was thus to investigate the effec...

The majority of human endometrial and ovarian cancers express receptors for GnRH type I (GnRH-I). Their proliferation is time- and dose-dependently reduced by GnRH-I and its analogs. GnRH-I analogs activate a phosphotyrosine-phosphatase (PTP) and inhibit EGF-induced mitogenic signal transduction. Recently we found that GnRH type II (GnRH-II) and its agonist [D-Lys6]GnRH-II also have antiprolife...

Background: During in vitro fertilization (IVF), fertility patients are expected to self-administer many injections as part of this treatment. While newer medications have been developed to substantially reduce the number of these injections, such agents are typically much more expensive. Considering these differences in both cost and number of injections, this study compared patient preference...

Sexually mature gilts (n = 20) were actively immunized against GnRH. Primary and booster immunizations of GnRH conjugated to bovine serum albumin induced production of antibodies in all gilts. Nineteen of the gilts became acyclic with suppressed concentrations of gonadotropins and estradiol. Intravenous challenges with 100 micrograms GnRH and 5 micrograms D-(Ala6, des-Gly-NH2(10)) ethylamide Gn...

INTRODUCTION Ovarian stimulation is employed in assisted reproduction techniques in order to obtain as many oocytes as possible. The early rise in oestradiol levels may lead to the premature end of the respective cycle. In order to avoid such an effect, pituitary suppression has been employed. The aim of this study was to evaluate whether maintenance or replacement of the type of GnRH analogue ...

OBJECTIVE To compare antimüllerian hormone (AMH) and antral follicle count (AFC) as predictors of ovarian response to controlled ovarian stimulation at individual fertility clinics. DESIGN Retrospective analysis of individual study center data in two multicenter trials. Centers that provided >10 patients were included in the analysis. SETTING A total of 19 (n = 519 patients) and 18 study ce...

PURPOSE Adenomyosis is a common, benign gynecological condition of the female reproductive tract characterized by heavy menstrual bleeding and dysmenorrhea. Gonadotropin-releasing hormone (GnRH) agonists are one of the medications used in adenomyosis treatment; however, their underlying mechanisms are poorly understood. Moreover, it is difficult to obtain endometrial samples from women undergoi...