Acquisition of a mature pattern of gonadotropin-releasing hormone (GnRH) secretion from the CNS is a hallmark of the pubertal process. Little is known about GnRH . Nachtigall LB, Boepple PA, Seminara SB, et al. Inhibin B secretion in males with gonadotropin-releasing hormone (GnRH) deficiency before and during long-term GnRH replacement: relationship to Cited by:
In patients previously exposed to prepubertal or adult levels of endogenous GnRH secretion (IGHD, IGD, AN at low body weight), a rapid initial FSH response occurred that subsequently declined when plasma estradiol rose to concentrations > pg/ml. Prior therapy with estrogen (micronized estradiol, Estrace) abolished FSH responses but LH. LH secretion may return to prepubertal levels, which is likely due to decreased GnRH secretion. While weight gain may restore patterns of LH and GnRH secretion, up to 50% may remain anovulatory; patients with anorexia nervosa additionally having a decrease in thyroid hormones.
a) the release of gonadotropin-releasing hormone (GnRH) from hypothalamic explants, b) serum sex hormone levels, and c) ovarian morphology, ovulation, and fertility. r: Neonatal exposure to BPA was associated with increased serum testosterone and estradiol levels, reduced progesterone in adulthood, and altered in vitro GnRH secretion. Animals. Differentiating between gonadotropin-releasing hormone (GnRH) deficiency and delayed puberty is difficult. A definitive diagnosis of GnRH deficiency is not .
To determine if abnormalities of GnRH secretion could account for the anovulation and amenorrhea, we measured plasma gonadotropins every 20 min for to h periods in 19 women with HA. Ovarian steroids and gonadotropin responses to an iv bolus dose of GnRH (25 ng/kg) were also measured. In the majority of physiologic conditions, the gonadal steroids feedback at the hypothalamus and pituitary to decrease GnRH and gonadotropin secretion. An exception is at the time of the periovulatory LH surge in females, believed to be due to positive feedback by rapidly rising estradiol levels.