title: Ewe Ovarian Tissue Vitrification: A Model for the Study of Fertility Preservation in Women.
abstract: Emergency in vitro fertilization followed by embryo vitrification is one feasible fertility preservation option for cancer patients. However, its clinical application has several limitations. Hormonal stimulation delays the initiation of oncotherapy and it is contraindicated in hormone-sensitive cancers or for use in pre-pubertal females. Vitrification of ovarian cortical tissue prior to the start of cancer treatment could be utilized for autotransplantation or for in vitro maturation of follicles enclosed in ovarian tissue. Nevertheless, the main concern associated with autotransplantation is the risk of malignant cell re-introduction to the patient, which is non-existent with the use of follicular in vitro culture. Since obtaining ovarian tissues from women for research is challenging and experimental studies are difficult to complete due to ethical issues, exploring the alternative usage of animal models for fertility preservation may provide beneficial insight into the prospects of follicular culture as an alternative for fertility restoration following ovarian tissue vitrification. Similarities between ewe and human ovary structures, as well as in ovarian follicular development dynamics, make the ewe a possible animal model for the study of female fertility preservation. As vitrification of ovarian tissue has the potential to cryopreserve preantral ovarian follicles, the present review will describe the progress of ovarian tissue vitrification studies completed in ewes.
authors.affiliation: School of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Ovarian Preantral Follicles (LAMOFOPA), State University of Ceara, Fortaleza, Ceara, Brazil.
authors.forename: Franciele Osmarini
authors.initials: FO
authors.lastname: Lunardi
authors.affiliation: North Dakota State University, Department of Animal Sciences, Fargo, North Dakota, USA.
authors.forename: Casie Shantel
authors.initials: CS
authors.lastname: Bass
authors.affiliation: School of Medicine of Ribeirão Preto, Department of Gynecology and Obstetrics, University of São Paulo, São Paulo, Brazil.
authors.forename: Marcelo Picinin
authors.initials: MP
authors.lastname: Bernuci
authors.affiliation: Health Center, University of Fortaleza (UNIFOR), Edson Queiroz, Fortaleza, Ceará, Brazil.
authors.forename: Roberta Nogueira
authors.initials: RN
authors.lastname: Chaves
authors.affiliation: School of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Ovarian Preantral Follicles (LAMOFOPA), State University of Ceara, Fortaleza, Ceara, Brazil.
authors.forename: Laritza Ferreira
authors.initials: LF
authors.lastname: Lima
authors.affiliation: School of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Ovarian Preantral Follicles (LAMOFOPA), State University of Ceara, Fortaleza, Ceara, Brazil.
authors.forename: Renato Félix da
authors.initials: RF
authors.lastname: Silva
authors.affiliation: School of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Ovarian Preantral Follicles (LAMOFOPA), State University of Ceara, Fortaleza, Ceara, Brazil.
authors.forename: José Ricardo de
authors.initials: JR
authors.lastname: Figueiredo
authors.affiliation: School of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Ovarian Preantral Follicles (LAMOFOPA), State University of Ceara, Fortaleza, Ceara, Brazil.
authors.forename: Ana Paula Ribeiro
authors.initials: AP
authors.lastname: Rodrigues
keywords: Vitrification; ewes; in vitro culture; ovary; preantral follicle