Victoria Keros

• MD, PhD
• Karolinska Institute and University Hospital

STUDY QUESTION Twenty years after the inception of the first fertility preservation programme for pre-pubertal boys, what are the current international practices with regards to cryopreservation of immature testicular tissue? SUMMARY ANSWER Worldwide, testicular tissue has been cryopreserved from over 3000 boys under the age of 18 years for a vari...

The full text is available at: https://haematologica.org/article/view/haematol.2021.278828

Two basic methods for the laboratory-focused cryopreservation of mammalian oocytes are described, based on work with murine oocytes. One method uses a relatively low concentration of the cryoprotectant propanediol plus sucrose and requires controlled rate cooling equipment to achieve a slow cooling rate. This method has also produced live births fr...

Two basic methods for the laboratory-focused cryopreservation of mammalian oocytes are described, based on work with murine oocytes. One method uses a relatively low concentration of the cryoprotectant propanediol plus sucrose and requires controlled rate cooling equipment to achieve a slow cooling rate. This method has also produced live births fr...

Study question: Does chemotherapy exposure (with or without alkylating agents) or primary diagnosis affect spermatogonial quantity in human prepubertal testicular tissue? Summary answer: Spermatogonial quantity is significantly reduced in testes of prepubertal boys treated with alkylating agent therapies or with hydroxyurea for sickle cell disea...

There are several methods of fertility preservation available for female patients facing infertility following gonadotoxic treatment of cancer or systemic disease. Embryos, oocytes or ovarian tissue can be cryopreserved and stored until the time when the patient is cured of her main disease and is expecting parenthood. The individual's choice depen...

One of the characteristic symptoms in girls and women with Turner syndrome (TS) is ovarian failure with infertility. Puberty starts spontaneously in 15% to 30% of girls with this syndrome but less than 5% reach menarche with the possibility of becoming pregnant because ovarian follicles secreting estrogen disappear prematurely. In a prior study, th...

Controlled-rate freezing of ovarian cortical tissue for preservation of fertility among young women facing chemo- or radio-therapy is a widely accepted procedure. To improve the method for cryopreservation of ovarian tissue, particularly the stroma, we carried out a systematic comparison of vitrification versus slow programmed freezing. Ovarian tis...

Increasing survival rates in young cancer patients, new reproductive techniques and the growing interest in quality of life after gonadotoxic cancer therapies have placed fertility preservation as an important issue to oncologists, fertility specialists and patients. Several techniques are now available for fertility preservation in these patients....

Isolation of spermatogonial stem cells before potentially sterilizing cancer therapy, followed by transplantation of these cells into the testis after such treatment, may be an effective approach to prevent infertility among prepubertal boys suffering from acute lymphoblastic leukemia (ALL). A key clinical consideration in this context is the timin...

Many girls with Turner syndrome have follicles in their ovaries at adolescence. Objective: Our objective was to study which girls might benefit from ovarian tissue freezing for fertility preservation. Design: Clinical and laboratory parameters and ovarian follicle counts were analyzed among girls referred by 25 pediatric endocrinologists. Fifty-sev...

Banking of testicular tissue from pre-pubertal boys before gonadotoxic treatment is a crucial step in fertility preservation. We wanted to find optimal methods for cryopreservation of testicular tissue from pre-pubertal boys, modifying techniques developed for fetal and adult human testicular tissue cryopreservation. Testicular tissue was collected...

Cryopreservation of testicular tissue is an option in fertility preservation for pre-pubertal boys who will lose spermatogenic cells as a result of chemotherapy. We compared three different protocols and cryoprotectants in cryopreservation of testicular tissue. Testicular tissue obtained from 16 infertile men was evaluated by light microscopy(LM),...