Background: The long protocol has been recognized as the gold standard in controlled ovarian hyperstimulation (COH). However, full dose of gonadotropin-releasing hormone agonist (GnRH-a) under prolonged become increasingly popular China. This study sought to compare pregnancy outcomes among following 3 groups: a group, and 2 types improved groups.

The hypothalamus regulates the secretion of anterior pituitary hormones via release of releasing hormones into the hypophysial portal vasculature. Additional neuromessengers act at the pituitary to modulate responses to the hypothalamic hormones. For example, neuropeptide Y enhances the effect of gonadotropin-releasing hormone and the response to the prolactin-inhibiting hormone dopamine.

A study was conducted to determine whether treatment with deslorelin, a gonadotropin-releasing hormone (GnRH) analog, produced anestrus in gilts and to test the ability of exogenous gonadotropin treatment with a combination of 400 IU equine chorionic gonadotropin and 200 IU human chorionic gonadotropin to induce estrus in GnRH analog-treated gilts. Twelve days after the third estrus, 11 gilts e...

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...

Although it is well established that the secretory activity of the corpus luteum absolutely depends on the presence of pituitary-derived luteinizing hormone (LH), it is unknown why the life span of the corpus luteum is extended during early pregnancy by the placental production of chorionic gonadotropin (CG) but regresses in the presence of LH despite the fact that CG and LH have similar action...