[Gestation in sheep after autotransplantation with cryopreserved ovarian tissue: evidence for oocyte viability after the freezing and transplantation procedures].
Freezing ovarian tissue is acquiring a greater significance due to the increase in oocyte long term survival rates, which provides young women with malignancies an alternative to preserve their fertility.


OBJECTIVE
1. Assessing the physiological viability of ovarian tissue auto-transplants. 2. Determining possible differences between the two cryoprotectors that were used: dimethyl sulfoxide (DMSO) and propanediol (PROH).


METHODS
Experimental and prospective study assessing ovarian tissue viability after freezing and auto-transplantation in eight female sheep.


METHODS
A bilateral oophorectomy was performed on the sheep under general anesthesia. The ovarian cortex was dissected and frozen using either DMSO (1.5 M) or PROH (1.5) with saccharose. The thawed tissue was auto-transplanted within the following one to six months, and weekly progesterone measurements were carried out in order to assess ovarian tissue functionality. Once ovulation levels were obtained, the female sheep were continuously exposed to the male in order to obtain the gestation process.


RESULTS
Ovulation activity was recovered in seven of the eight female sheep (87.5%) submitted to auto-transplants within an average period of time of 62.8 +/- 9.1 days, as evidenced by serum progesterone levels. These findings were obtained regardless of the cryoprotector used. Two gestations were obtained, and these are evolving normally, as assessed by ultrasonic methods.


CONCLUSIONS
The present study shows that ovarian function is adequately restored in oophorectomized sheep using ovarian tissue auto-transplantation, and produced the first pregnancies obtained through this technique in Latin America. It is possible to assume that these results can be reproduced in women.
Gutiérrez Gutiérrez
Antonio
A
Instituto de Ciencias en Reproducción Humana (VIDA), León.
Vargas Aguirre
Marco Antonio
MA
Corona Martha
Angélica
A
Becerra
Echeverri
E
González Ortega
Claudia
C
Mendoza Hurtado
Sergio
S
Monroy Avendaño
Edith
E
Tovar Caballero
Guillermo
G
D000818:Animals; D015925:Cryopreservation; D003451:Cryoprotective Agents; D004121:Dimethyl Sulfoxide; D005260:Female; D009926:Organ Preservation; D010052:Ovariectomy; D010053:Ovary / Q000502:physiology* / Q000637:transplantation*; D010060:Ovulation / Q000502:physiology*; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000502:physiology*; D011409:Propylene Glycols; D011446:Prospective Studies; D020127:Recovery of Function; D012756:Sheep; D014182:Transplantation, Autologous
D003451:Cryoprotective Agents; D011409:Propylene Glycols; D004121:Dimethyl Sulfoxide
Gestaciones en ovejas autotrasplantadas con tejido ovárico criopreservado: evidencia de viabilidad ovocitaria posterior al proceso de congelación y trasplante.