Oocyte Freezing is a process in which a woman's eggs (oocytes) are extracted, frozen and stored as a method to preserve reproductive potential in women of reproductive age. Oocyte Freezing has advanced greatly over the past few years, with improved overall success of eggs surviving the freezing process.
Oocyte Freezing can be considered for a variety of reasons:
• Women with cancer requiring chemotherapy and/or pelvic radiation therapy that may affect fertility.
• Surgery that may cause damage to the ovaries.
• Risk of premature ovarian failure because of chromosomal abnormalities (e.g. Turner syndrome, fragile X syndrome), or family history of early menopause.
• Ovarian disease with risk of damage to the ovaries.
• Genetic mutations requiring removing the ovaries (e.g. BRCA mutation).
• Fertility preservation for social or personal reasons to delay childbearing.
How is Oocyte Freezing conducted?
The first step in the Oocyte Freezing process is the ovarian stimulation which is carried out in the same manner that is used with in vitro fertilization (IVF), using injectable hormonal medications. Following the stimulation, the oocytes and the surrounding fluid in the ovarian follicles are aspirated vaginally while under sedation.
The maturity of the eggs is assessed under the microscope, and those that are mature are cryopreserved or freezed. Currently, vitrification is the method of choice for Oocyte Freezing, and this is achieved by ultra-rapid cooling into liquid nitrogen where they can be stored.