Hypothalamic-pituitary-ovarian

Physiologic causes Adolescence Perimenopause Immaturity of the hypothalamic-pituitary-ovarian axis no LH surge Declining ovarian function... 

Clomiphene is a nonsteroidal agent with oestrogenic and anti-oestrogenic properties. The mechanism of action is not precisely clear, but it ultimately leads to the release of the pituitary gonadotropins FSH and LH. It stimulates ovulation in anovulatory or oligo-ovulatory women with adequate endogenous oestrogen activity and an intact hypothalamic-pituitary-ovarian axis. 

Mizutani, T., et al. 1995. Danazol concentrations in ovary, uterus, and serum and their effect on the hypothalamic-pituitary-ovarian axis during vaginal administration of danazol suppository. Fertil Steril 63 1184. 

Compounds within this class of substances can inhibit hypothalamic-pituitary-ovarian axis function by inhibiting gonadotropin secretion. Subsequently ovulation and estrus is suppress leading to infertility or reduced fertility. 

D. K. Sarkar, S. J. Friedman, S. S. C. Yen, and S. A. Frautschy, Chronic inhibition of hypothalamic-pituitary-ovarian axis and body weight gain by brain-directed delivery of estradiol-17P in female rats, Neuroendocr. 50 204 (1989). 

The steroidal antiestrogens ICI 164,384, ICI 182,780, and EM-139 are devoid of estrogenic activity in the mammary gland, uterus, and hypothalamic-pituitary-ovarian axis (Labrie et al., 1992b Wakeling and Bowler, 1988b). 

The chance of a spontaneous conception as well as the prognosis of infertility therapy can only be determined when there is some knowledge about the remaining capacity for reproduction (S8). Measuring ovarian reserve is the cornerstone of most tests designed to predict the success of infertility therapy. In Fig. 1, a representation of the hypothalamic-pituitary-ovarian axis is shown. However, there are more factors determining the chance of success in assisted reproduction. The... 

Fig. 1. The major hypothalamic-pituitary-ovarian interactions mentioned in different parts of this review. Ovarian steroids exert effects on the secretion of GnRH and gonadotropins.

Apter D. Development of the hypothalamic-pituitary-ovarian axis, Ann NY Acad Sci 1997 816 9-21. 

Young EA, Midgley AR, Carlson NE, Brown MB. Alteration in the hypothalamic-pituitary-ovarian axis in depressed women. Arch Gen Psychiatry 2000 57 1157-1162. 

An autoradiographic study of in vitro DNA synthesis of the endometrium of women on a continuous low dose (500>ig/day) of chlormadinone acetate (2) did not reveal differences from a control group, thus appearing to demonstrate normal hypothalamic-pituitary-ovarian function in the treated group. 

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