COMPARISON OF ORTHOTOPIC (OA) AND HETEROTOPIC (HA) AUTOLOGOUS CRYOPRESERVED OVARIAN TISSUE TRANSPLANTATION (ACOTT) OUTCOMES

Abstract

Since the first success with ACOTT in 2000, two main surgical approaches have emerged. In the orthotopic approach (OA), tissues are transplanted in the pelvis, where spontaneous conception is possible. In the heterotopic approach (HA), tissues are generally placed at extra-pelvic locations, where IVF is required for conception. While the majority of the ACOTT cases have been performed with OA, no study has compared the two approach. The objective of this study was to compare the outcomes of the OA and HA ACOTT. Of the 12 participants, 6 each received OA vs. HA transplants. Primordial follicle density was assessed prior to the transplant to guide the amount of tissue to be grafted. All OA and one HA ACOTT was performed with robotic surgery. Remaining HA ACOTTs were performed subcutaneously, under local anesthesia. All women underwent egg/embryo cryopreservation to preempt graft function cessation or because they could not otherwise conceive (hysterectomy, radiation damage, heterotopic transplant). The mean ages at cryopreservation and transplantation were higher for the HA ACOTT recipients than the OA. All transplants resulted in the restoration of ovarian endocrine function. The primordial follicle density, % ovarian cortex transplanted, graft longevity, time to graft function and oocyte yields were similar between the two groups. However, fertilization rates and the embryo quality were significantly impaired in the heterotopic transplant group compared to the orthotopic (Table). While 4 of 6 women conceived and delivered 6 children in the OA group, only a patient had 3 livebirths after the HA ACOTT.Tabled 1VariableOrthotopic (n=6)Heterotopic (n=6)p-valueAge at Cryopreservation20.3 ± 2.7 (16 - 23)31.3 ± 4.2 (28 - 37)0.0003Age at Transplantation30.2 ± 3.8 (26 - 35)36 ± 4 (30 - 42)0.04PDF Density (mm2)1 ± 0.9 (0.39 – 2.87)0.88 ± 0.6 (0.45 - 1.3)NS% Ovary Transplanted51 ± 6.5 (41 - 58)59 ± 35.9 (32 - 100)NSTime to Function (wks)14.8 ± 4.7 (11 - 23)13.7 ± 4.5 (8 - 20)NSLongevity (mo)44.3 ± 25.6 (18 - 91)33.7 ± 21.1 (10 - 72)NS# Oocytes15.6 ± 11.5 (1 - 30) †10.6 ± 8.3 (1 - 20)NSFertilization %97 ± 4.1 (92 - 100)12.5 ± 17.7 (0 – 87.5)0.0001# Non-arrested Embryos10 ± 0.82 (9 - 10) †2 ± 1.7 (1 - 4)0.0001 Open table in a new tab OA ACOTT results in superior embryo quality, compared to the HA. However, endocrine function rate and longevity are similar between the two approaches. We propose that, when feasible, OA should be preferred for those who intend to conceive, while the HA ACOTT can be performed for those who only desire ovarian endocrine function, especially since the latter can be performed under local anesthesia.