Melatonin receptor expression exhibits profound developmental changes through poorly understood mechanisms. In mammals, a current model suggests that pubertal reactivation of gonadotrophin-releasing hormone (GnRH) secretion down-regulates MT1 melatonin receptors in pituitary gonadotroph cells, via the induction of early growth response factor-1 (EGR-1). Here we have examined this model by testi...

background: premature luteinization during in vitro fertilization was commonly happened before the introduction of gnrh analogues. high level of unwanted progesterone is associated with adverse pregnancy outcome and is thought to be induced by inappropriate lh elevation.objective: to evaluate the progesterone level on the day of human chorionic gonadotropin (hcg) triggering in gnrh agonist and ...

BACKGROUND Patients with polycystic ovary syndrome (PCOS) may need a longer period of pituitary downregulation to suppress the elevated serum LH and androgen levels effectively during IVF treatment using the GnRH agonist long protocol. We proposed a stimulation protocol incorporating Diane-35 and GnRH antagonist (Diane/cetrorelix protocol) and compared it with the GnRH agonist long protocol for...

In an attempt to resolve the apparent controversy in the observed effects of gonadotrophin-releasing hormone (GnRH) analogues on the ovary, conventional binding studies were conducted with a GnRH agonist and an antagonist in various ovarian tissues to demonstrate possible GnRH receptor binding. In human luteinized granulosa cells derived from unstimulated in-vitro fertilization cycles, high aff...

Pituitary adenylate cyclase-activating polypeptide (PACAP) releases LH and FSH from anterior pituitary cells. Although this effect is relatively weak, it has a strong sensitizing action on GnRH-induced gonadotropin secretion. Here we investigated the possibility that ovarian steroids, which are well-known modulators of LH secretion, interact with PACAP and GnRH in pituitary gonadotrophs. Rat pi...

Abstract Study question Is there a difference, in terms of ovarian yield and sensitivity, comparing progestin-primed protocols (PPOS) to GnRH antagonist (GnRH-ant) using different follitropin? Summary answer PPOS is an effective choice, with both follitropis. Nevertheless, could improve sensitivity FSHu increasing the number oocyte without compromising quality. What known already The use new st...

OBJECTIVE To demonstrate the feasibility of scheduling an IVF cycle, without disadvantages, in the new patient friendly stimulation protocol using the long acting Corifollitropin Alfa, in combination with GnRH-antagonist protection and GnRH-agonist triggering. STUDY DESIGN Two groups of ten patients were admitted in the study. Both received the same stimulation protocol with Corifollitropin A...

Gonadotrophin-releasing hormone (GnRH) agonists are widely used in the treatment of women with symptomatic leiomyomas. The effectiveness of this treatment, as far as symptoms are concerned, is well established, and in recent years many studies have contributed to defining the optimal role for GnRH agonists. Side-effects and health risks prohibit the long-term use of these compounds. The combine...