Effect of long-term exposure at suprazero temperatures on activity and viability of human ovarian cortex  Evgenia Isachenko, Ph.D., Vladimir Isachenko, Ph.D., Frank Nawroth, M.D., Ph.D., Gohar Rahimi, M.D., Ph.D., Juergen M. Weiss, M.D.  Fertility and Sterility  Volume 91, Issue 4, Pages 1556-1559 (April 2009) DOI: 10.1016/j.fertnstert.2008.09.068 Copyright © 2009 American Society for Reproductive Medicine Terms and Conditions

Figure 1 Example of typical developmental stages of follicles after different SZT exposure before subsequent in vitro culture. (A) Control. The ovarian cortex was fixed immediately after recovery. Primordial follicle (single asterisk): the oocyte surrounded by flattened pregranulosa cells (arrowhead). Primary follicle (double asterisk): the oocyte surrounded by flattened pregranulosa cells and few columnar and cubic granulosa cells (arrows). Developmental stages of follicles at (B) 0 hours, (C) 15 hours, and (D) 36 hours are shown: primordial follicle (asterisk), primary follicle (cross), secondary follicle (arrow), and secondary follicle (arrowhead) with early antrum development (small arrowheads). Different superscripts denote the statistically significant difference (P<.05). Early antrum formation was noted only in group 1 (0 hours of exposure to STZ). Fertility and Sterility 2009 91, 1556-1559DOI: (10.1016/j.fertnstert.2008.09.068) Copyright © 2009 American Society for Reproductive Medicine Terms and Conditions