Animal age, weight and estrus cycle stage impact the quality of in vitro grown follicles. Related Articles Animal age, weight and estrus cycle stage impact the quality of in vitro grown follicles. Hum Reprod. 2011 Sep;26(9):2473-85 Authors: Hirshfeld-Cytron JE, Duncan FE, Xu M, Jozefik JK, Shea LD, Woodruff TKOriginal Article