There is the global tendency to the later marriage and postponing childbearing desire in industrial countries, thus many epidemiological observations point out that almost one-tenth of reproductive-aged women require infertility treatment in these countries. Preserving future fecundity is generally understood as preserving ovarian function, and it is becoming a major matter of concern for these women and for physicians specialized in reproductive medicine.

Recent advances in assisted reproductive technologies enabled cryopreservation of eggs and ovarian tissue more efficient. In addition, the concept of ovarian reserve has been introduced in daily clinics and several biomarkers of the ovarian reserve have been developed. Among them, anti-mullerrian hormone is one of the most superior and important marker of ovarian reserve, and a statistical model to predict the reduction of anti-mullerrian hormone has been proposed.

Age-related fertility decline is a striking phenomenon for women and universally occurs in human being. Reproductive organs involve the ovary and the uterus. Although the uterus is somewhat affected by ageing, the ageing of the ovary is considered to be the main issue and an inevitable phenomenon. After the publication of the notion that the germ cell production has been finished in females prior to the birth and ovarian follicular pool is gradually but irreversibly diminished by the age of 40 to 50, spontaneous exhaustion and deterioration of follicular pool have been attributed to the cause of ovarian ageing.

Several chemicals have been proved to improve or maintain the ovarian follicular pool though the efficacy is still limited. Except for the cryopreservation of eggs that fertilized, oocytes or ovarian tissue itself, few promising modalities have been established for preserving ovarian follicular pool. However, recent research in ovarian physiology revealed novel microenvironment of ovarian follicles. Herein we would like to overview the progress of ovarian function including follicular pathophysiology, development of ovarian markers, drugs that maintain or improve ovarian reserve, and technologies of cryopreservation of oocyte and ovarian tissues.

_ Articles that focus on the following sub-topics are of high interest:
_ Novel and recent findings regarding ovarian follicular development;
_ How we measure the ovarian follicle pool mathematically;
_ Follicular pool exhaustion; and
_ The importance of oxidative stress in the ovary.

Keywords: Ovary, Ageing, Ovarian reserve, Follicle growth, Cryopreservation, Assisted reproductive technology

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