Premature ovarian failure (POF) occurs in women under the age of 40 y with primary or secondary hypergonadotropic amenorrhea and accompanied by estrogen deficiency in 75% of cases. None of the women with primary amenorrhea have been reported to ovulate or conceive with their own oocytes, but more than a third of the women were pregnant atleast once before developing hypergonadotropic POF. It is speculated that lack of follicular renewal may be caused by age-associated exhaustion of specific memory cells in the lymphoid system and bone marrow that are necessary to generate effector cells migrating to ovaries and stimulating transformation of OSE cells into primitive granulose and germ cells. POF may be caused by delayed ovarian development during immunological adaptation, by earlier termination of immunological adaptation or by cytostatic chemotherapy affecting both the existing pool of primary follicles and committed Ovary specific mesenchymal cells(O-SMCs) required for the follicular renewal (Reviewed by Bukovsky A et al.,2006).
POF is also often associated with follicular resistance to gonadotropins called hypergonadotropic amenorrhea where ovaries contain normal primary and antral follicles not responding to gonadotropins by production of estrogen(Reviewed by Bukovsky A et al., 2006).
Studies with laboratory animal models have showed that there are two types of POF with primary and antral follicles within the ovaries. The first persistent ovarian immaturity can be induced by inhibition of ovarian development (i.e inhibition of androgen receptor expression with estrogens) during immunological adaptation. The second premature ovarian ageing can be induced by the acceleration of ovari...
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... Genet. 1998 Mar;18(3):231-6.
Cohen J, Scott R, Alikani M, Schimmel T, Munné S, Levron J, Wu L, Brenner C, Warner C, Willadsen S. Ooplasmic transfer in mature human oocytes. Mol Hum Reprod. 1998 Mar;4(3):269-80.
Barritt JA, Brenner CA, Malter HE, Cohen J. Mitochondria in human offspring derived from ooplasmic transplantation. Hum Reprod. 2001 Mar;16(3):513-6.
Barritt J, Willadsen S, Brenner C, Cohen J. Cytoplasmic transfer in assisted reproduction. Hum Reprod Update. 2001 Jul-Aug;7(4):428-35.
Harvey AJ, Gibson TC, Quebedeaux TM, Brenner CA. Impact of assisted reproductive technologies: a mitochondrial perspective of cytoplasmic transplantation. Curr Top Dev Biol. 2007;77:229-49.
Acton BM, Lai I, Shang X, Jurisicova A, Casper RF. Neutral mitochondrial heteroplasmy alters physiological function in mice. Biol Reprod. 2007 Sep;77(3):569-76.
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