Ovarian Autograft After Cryopreservation. A Laparoscopic Approach in Ewes

Abstract

The objective of the study was to develop a laparoscopic technic for ovarian autograft, based on our usual laparotomic way. Fertility preservation in cancer therapy must be developed also for women. Ovarian cryopreservation seems to be an interesting technique. Freezing processes are always studied, and slow cooling is probably the more efficient. The place to graft is also discussed, and orthotopic neither heterotopic graft has proved to be a standard. We tested for several years, orthotopic graft, in order to obtain pregnancy more easily. Laparoscopy seems to be the lightest solution to this point of view. We tested our orthotopic graft technique through laparoscopy, in 12, 6 to 12 month-old, ewes. The left ovary was removed by laparoscopy and cut in half. In group 1 (N=6), the graft was performed immediately on the right ovary, and in group 2 (N=6), after the freezing/thawing protocol. The second hemi-ovary served as an ungrafted control fragment. A polypropylene/polyglactin mesh was included between graft and base to separate the two structures during histological analysis. The number and aspect of adhesions found in a laparotomy 3 months post-operatively was registered. Follicle number and aspect in the grafts, on histological analysis, were counted. Freezing is safe for primordial follicles, even if global anomaly rate (cytoplasm plus nuclear anomaly) increased after freezing (p < .05). Only one pelvic adhesion occurs in one ewe. The survival rate for primordial follicle after grafting was 6.3% ± 2.3 in group 2 (Freezing/thawing protocol) and 5.1% ± 2.8 in group 1 (immediate graft). The graft performance time decreased with experience, the mean time was 71 min in group 1 and 51 min in group 2. Laparoscopy seems to be a well-adapted technique for ovarian orthotopic autograft. The main follicle loss occurs before graft revascularization.