Restoration of ovarian steroid secretion and histologic assessment after freezing, thawing, and autograft of a hemi-ovary in sheep

Objective: To evaluate the effects of freezing, thawing, and autograft of a hemi-ovary on steroid secretion, endometrial maturation, and ovarian histo logy in ewes. Design: Experimental animal study. Setting: Laboratoire de Zootechnie, Ecole Nationale Veterinaire, Marcy l'Et oile, France. Animal(s): Six lambs aged 6 months to 1 year old. Intervention(s): Hemi-ovaries were prepared and frozen from the right ovary of six lambs and autografted 4 weeks later to the contralateral ovarian hi lus. The autografts and the uterus were recovered 1 year later. Blood tests were performed each week to measure P concentration. Main Outcome Measure(s): Number of primordial follicles; levels of plasma P . Result(s): Histologic examination of ovarian slices after freezing showed n o destruction of primordial, primary, secondary, or cavitary follicles. The frozen ovarian autograft showed good recovery of the macroscopic and micro scopic ovarian structure. After autografting, histologic examination reveal ed primordial to cavitary follicles. Secretion of P started to rise 4 weeks after the autograft. Histologic analysis of the endometrium showed numerou s glands, vessels, and mucous secretion. Conclusion(s): Frozen ovarian autografts achieved P secretion and endometri al maturity. (C) 1999 by American Society for Reproductive Medicine.