Assessment of ovarian cortex follicles in chemotherapy naïve and chemotherapy exposed patients.

Background: Histological evaluation of ovarian tissue harvested as part of the attempt to preserve fertility might clarify the mechanism by which ovarian failure is caused. The purpose of this study was to compare the histologic appearance of ovarian tissue harvested for ovarian tissue cryopreservation (OTC) in chemotherapy naïve and chemotherapy exposed patients regarding the presence of follicles in different stages of development and to explore ovarian tissue histology in patients exposed to low- and high-cytotoxicity risk chemotherapy.

Methods: A cohort of post-pubertal cancer survivors who underwent OTC between 1997 and 2018 was evaluated.

Maturation of Oocytes Obtained from Ovarian Cortex Among Postpubertal Hematological Cancer Patients Undergoing Fertility Preservation.

maturation (IVM) of oocytes obtained from ovarian tissue during ovarian tissue cryopreservation (OTC) is a technique for fertility preservation in patients with cancer obviating the need to postpone chemotherapy initiation. Little is known about IVM outcomes in hematological malignancies, especially post-chemotherapy. The purpose of this study was to evaluate the effect of cytotoxic treatment on the potential to retrieve immature oocytes and mature them and examine the association between serum inflammatory markers and these results.

Prior exposure to chemotherapy does not reduce the in vitro maturation potential of oocytes obtained from ovarian cortex in cancer patients.

Study Question: Does chemotherapy exposure affect IVM potential of immature oocytes retrieved from the ovarian cortex following ovarian tissue cryopreservation (OTC) for fertility preservation?

Summary Answer: The IVM potential of oocyte retrieved from ovarian cortex following OTC is not affected by prior exposure to chemotherapy but primarily dependent on patient's age, while successful retrieval of immature oocytes from the ovarian tissue is negatively affected by chemotherapy and its timing.

What Is Known Already: The potential and feasibility of IVM in premenarche patients was previously demonstrated, in smaller studies. The scarce data that exist on the IVM potential of oocytes retrieved during OTC following chemotherapy support the feasibility of this process, however, this was not previously shown in the premenarche cancer patients population or in larger cohorts.

Pre-pubertal oocytes harbor altered histone modifications and chromatin configuration.

Pre-pubertal oocytes are still dormant. They are arrested in a GV state and do not undergo meiotic divisions naturally. A multitude of molecular pathways are changed and triggered upon initiation of puberty.

Establishment of a controlled slow freezing-based approach for experimental clinical cryopreservation of human prepubertal testicular tissues.

Objective: To develop an efficient, clinical-grade, freezing protocol toward experimental clinical cryopreservation of testicular tissues in prepubertal boys suffering from cancer.

Design: Experimental cryopreservation of testicular tissue.

Setting: University Medical Center.

Dydrogesterone supplementation in addition to routine micronized progesterone administration for luteal support in cycles triggered with lone GnRH agonist results in an acceptable pregnancy rate and avoids the need to freeze embryos.

Background: Ovarian hyperstimulation syndrome (OHSS) is reduced when using antagonist cycle with gonadotrophin releasing hormone (GnRH) agonist trigger before ovum pick up. This trigger induces short luteinizing hormone (LH) and follicle stimulating hormone (FSH) peaks, resulting in an inadequate luteal phase and a reduced implantation rate. We assessed whether the luteal phase can be rescued by supplementing with oral dydrogesterone (duphaston) in antagonist cycles after a lone GnRH agonist trigger.

Age-Dependent Maturation Efficacy of Human Oocytes - Is There an Optimal Age?

maturation of oocytes from antral follicles seen during tissue harvesting is a fertility preservation technique with potential advantages over ovarian tissue cryopreservation (OTC), as mature frozen and later thawed oocyte used for fertilization poses decreased risk of malignant cells re-seeding, as compared to ovarian tissue implantation. We previously demonstrated that maturation (IVM) performed following OTC in fertility preservation patients, even in pre-menarche girls, yields a fair amount of oocytes available for IVM and freezing for future use. We conducted a retrospective cohort study, evaluating IVM outcomes in chemotherapy naïve patients referred for fertility preservation by OTC that had oocyte collected from the medium with attempted IVM.

In vitro maturation rates in young premenarche patients.

Objective: To evaluate in vitro maturation (IVM) efficacy and oocyte retrieval rates after ovarian tissue cryopreservation in young premenarche girls facing chemo- and radiotherapy.

Design: A retrospective cohort study.

Setting: University-affiliated tertiary medical center.

Single-Incision Laparoscopic Surgery for Ovarian Tissue Cryopreservation.

Study Objective: To present single-incision laparoscopic surgery (SILS) as an alternative to standard multiport laparoscopic surgery (MPLS) for ovarian tissue cryopreservation.

Design: Retrospective cohort study (Canadian Task Force classification II-2).

Setting: Tertiary medical center.

Iron chelators: correlation between effects on Plasmodium spp. and immune functions.

Iron chelating agents, which permeate through erythrocytic and parasite membranes, are effective against Plasmodium falciparum in vitro. However, the protective effect in humans is transient. We examined the antiplasmodial capacity of several iron chelators in vitro and in vivo.