Comments for Event:1883
- Hummitzsch K, Irving-Rodgers HF, Hatzirodos N, Bonner W, Sabatier L, Reinhardt DP, et al. A New Model of Development of the Mammalian Ovary and Follicles. PLOS ONE. 2013;8(2):e55578.
- Monniaux D, Cadoret V, Clément F, Dalbies-Tran R, Elis S, Fabre S, et al. Folliculogenesis. In: Huhtaniemi I, Martini L, editors. Encyclopedia of Endocrine Diseases (Second Edition). Oxford: Academic Press; 2019. p. 377-98.
- Hirshfield AN. Development of follicles in the mammalian ovary. Int Rev Cytol. 1991;124:43-101.
- Monniaux D. Factors influencing establishment of the ovarian reserve and their effects on fertility. Anim Reprod. 2018;15:635-47.
- Ge W, Li L, Dyce PW, De Felici M, Shen W. Establishment and depletion of the ovarian reserve: physiology and impact of environmental chemicals. Cellular and Molecular Life Sciences. 2019;76(9):1729-46.
Prajakta Ghume
On July 27, 2025 01:09
In mammals, the process of forming primordial germ cells within the epiblast, begins in the human ovary at approximately 2 weeks post-conception (wpc), corresponding to 4 weeks of gestation. During this stage, these germ cells migrate to the hindgut and later settle in the gonadal ridges before 7 wpc. Once in the gonadal ridges, the germ cells proliferate to form ovarian cysts or nests as oogonia. These cysts also contain primordial granulosa cells, which derive from the gonadal ridges and contribute to the formation of future ovarian follicle(Hummitzsch K. et al.2013) The meiotic prophase begins around 8.5 wpc, at which point the oogonia can stop mitosis, grow, and mature into primary oocytes. Primordial follicles with a diameter of 30 mm are produced when the cysts break apart, which occurs within 13 and 30 weeks. According to current theories, the newly produced primordial follicles serve as the female's limited supply of resting oocytes for the duration of her reproductive life (Monniaux D et al. 2019, Hirshfield AN 1991). The establishment and gradual depletion of the ovarian reserve is a fundamental and conserved biological process across mammals. In species such as humans, rodents, sheep, and cattle, primordial follicle formation occurs through similar mechanisms, including oocyte nest breakdown, somatic cell interaction, and the initiation of meiosis. Although the timing of reserve establishment is species-specific—the structural and functional processes are conserved. Cross-species relevance is further supported by the fact that exposure to reproductive toxic environmental chemicals (RTECs) has been demonstrated to impair the development and maintenance of ovarian reserves in both human and animal models. Accordingly, the key event is plausibility extends across the mammalian taxa with ovaries (Monniaux, D. 2018, Ge, W., et al. 2019).
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edited - July 27, 2025 01:10