Читать книгу Assisted Reproduction Techniques - Группа авторов - Страница 93

Cryopreservation of ovarian cortex may be the only fertility preservation option in prepubertal girls or in women who need cancer treatment within the minimum of 2 weeks required for controlled ovarian stimulation. OTC has been used to enable multiple ovulations and pregnancies in the future as well as for restoration of endocrine function [4]. With more than 130 babies born after ovarian tissue transplantation reported till 2017 [5], OTC has moved from being experimental to a more established method of fertility preservation in various countries [6,7,8]. However, it should only be offered by specialized centers with relevant clinical and laboratory expertise, facilities and appropriate accreditation, such as Human Tissue Authority (HTA) licensing in the UK.

Generally, no more than 50% of one of the ovaries is removed in a day‐case laparoscopic procedure (Figure 10.1), and the cortical tissue is prepared to a thickness of approximately 1mm, cut into small pieces and then cryopreserved [4]. If the woman becomes menopausal following her cancer treatment, she may have the ovarian cortical tissue transplanted as and when she decides to try to conceive a pregnancy.

There is a theoretical risk of transplantation resulting in the reintroduction of cancer cells. This risk can be mitigated by the use of in vitro maturation (IVM). The first live birth achieved using IVM in a woman with cancer has been reported in 2020 [9], and this could become an important option for fertility management. Nevertheless, a recent systematic review of all peer‐reviewed published reports of women receiving ovarian tissue transplantation has found no evidence of reseeding malignant cells present in the frozen ovarian tissue in sufficient numbers to cause recurrence of cancer [8].

Figure 10.1 Laparoscopic removal of part of an ovary. Stay suture to stabilize the ovary (a). Removal of 1/3‐1/2 of the cortex without the use of energy (b,c).

Images courtesy of Mr. Yousri Afifi, Birmingham Women’s Hospital, Birmingham, UK.