Fertility preservation options before cancer therapy starts
All women are born with a limited number of eggs. Over time, there is a natural decline in the number of remaining eggs until a woman reaches menopause. It is well-known that cancer treatment can quickly and dramatically reduce a woman’s supply of eggs, leading to premature menopause in 15-89% of patients after chemotherapy (2). Women receiving higher doses and certain types of chemotherapy, those who are older (particularly over 35) at the time of treatment, and those with Hodgkin’s disease are particularly at risk.
Because it is difficult to predict whether a woman will be fertile after cancer therapy, it is important to consider fertility preservation options before starting treatment.
What are the options before cancer therapy starts?
In Vitro Fertilization (IVF) and Embryo Freezing
Ideal option for women who have a male partner or are interested in using donor sperm. And women who can safely delay cancer treatment for 2-6 weeks.
Since by definition an embryo is an egg which has been fertilized by sperm, this process requires sperm. It is an excellent option for women who have a male partner or are interested in using donor sperm. It typically involves hormonal stimulation, which starts at the beginning of a menstrual period and lasts for approximately 10-14 days to mature the eggs. Alternative methods of stimulation can be used if exposure to high estrogen levels is a concern (as in breast cancer patients). The eggs are removed by an ultrasound-guided needle (a procedure which is done under sedation) and are then combined with the sperm. The resulting embryos can be stored indefinitely until the patient is ready to use them. The entire process takes between two and six weeks to complete.
Ideal option for women who do not have a male partner or are not interested in using donor sperm. And women who can safely delay cancer treatment for 2-6 weeks.
Recent technological advances have resulted in dramatic improvements in egg survival and pregnancy rates after egg freezing, and as of 2012, egg freezing is no longer considered experimental. At USC Fertility we have established our expertise with the technology, achieving a 64% survival rate, 63% pregnancy rate, and ten live births in our initial study, and we have achieved many more live births since then (5). These findings are encouraging and suggest that our technology of freezing eggs may be as successful as freezing embryos. Because successful egg freezing requires experience and expertise, it should be performed only at centers with proven success with egg freezing technology, and at USC Fertility we meet these criteria.
Like embryo freezing, this strategy typically requires a 10-14 day period of hormonal treatments to mature the eggs, thus making them suitable for freezing. It is a good option for patients who can safely delay their cancer therapy for two to six weeks.
Ovarian Tissue Freezing and In Vitro Maturation (IVM)
For patients whose cancer therapy cannot be delayed, ovarian tissue containing immature eggs can be removed by a minor surgical procedure (called laparoscopy) and preserved for future use. Because immature eggs cannot be fertilized, techniques to mature the eggs in the laboratory have been developed and refined over the past several decades (6), leading to consistent improvements in egg survival and fertilization. Reports of pregnancies and healthy live born babies resulting from this technology in women without cancer (7) and successful freezing of eggs matured in the laboratory in women with cancer (8) indicate that this strategy holds promise for fertility preservation in female cancer patients. This is an option for those patients who cannot or do not wish to delay their cancer treatment. Similar to egg freezing, ovarian tissue freezing is considered investigational and should be performed responsibly under ethics-board approved research protocols.
For women who require abdominal or pelvic radiation as part of their cancer therapy, it can be helpful to surgically move or suspend the ovaries (ovarian transposition) to minimize the amount of exposure to the radiation.
For women with cervical or ovarian cancer, fertility-sparing surgery may be an option depending on the stage and type of cancer. These surgical methods can be technically difficult and should only be performed by gynecologic oncologists with extensive experience with such procedures.