Comparison of orthotopic and heterotopic autologous ovarian tissue transplantation outcomes

Abstract

Objective: To compare the outcomes of orthotopic and heterotopic ovarian tissue transplantation (OTT) techniques.

Design: Mixed prospective-retrospective cohort study.

Setting: Academic hospital.

Patients: A total of 14 recipients of autologous OTT.

Interventions: Of the 14 women, 12 who received orthotopic (n = 6) or heterotopic (n = 6) transplants met the inclusion criteria. All orthotopic transplants and one heterotopic ovarian tissue transplant were performed laparoscopically. Although 5 of the 6 remaining heterotopic transplants were performed subcutaneously under local anesthesia or intravenous sedation, one was performed with robotic assistance. With the exception of one recipient who solely desired restoration of endocrine function, all underwent oocyte retrieval either to cryopreserve oocytes and embryos before the graft function ceased or because they could not otherwise conceive (hysterectomy, radiation damage, and heterotopic transplant).

Main outcome measures: Primary outcome measures were graft function and longevity, and the number of embryos generated per retrieval.

Results: The mean age at ovarian tissue harvesting and transplantation was lower in patients with orthotopic vs. heterotopic transplants, although the proportion of transplanted ovarian cortex was lower in heterotopic transplant cases. All grafts restored ovarian endocrine function. Fertilization rates, the number of embryos generated per retrieval, and the mean number of nonarrested embryos were significantly lower in heterotopic OTT. However, time to function and graft longevity were similar between the groups. Although 4 of the 6 women conceived and delivered 7 children among orthotopic ovarian tissue recipients, one recipient had 3 spontaneous live births after heterotopic OTT, presumably because of the induction of function in the remaining menopausal ovary.

Conclusions: It appears that orthotopic OTT results in higher gamete and embryo quality. However, the endocrine function restoration rate and longevity are similar between the 2 approaches. When feasible, orthotopic OTT should be preferred for those who intend to conceive, although a less invasive heterotopic OTT can be performed for those who primarily desire ovarian endocrine function.

Keywords: Fertility preservation; heterotopic transplantation; orthotopic transplantation; ovarian tissue transplantation; reproductive Surgery.