Using cryopreservation for future fertility
Fertility preservation is the act of preserving sperm, eggs or reproductive tissue, such as ovarian tissue, so that a person or couple can have biological children later in life.
While fertility preservation was originally designed for people undergoing medical treatments that affect long-term fertility, it is now also used for social reasons. This is when individuals or couples elect to delay having children because they want to pursue careers or are just not ready to have a family yet.
Cryopreservation is a form of fertility preservation that involves freezing sperm, eggs, blastocysts, embryos or whole tissues and storing them so that they can be used later.
During cryopreservation fertility lab technicians use liquid nitrogen to freeze the materials to sub-zero temperatures. At these low temperatures any biological activity, including the biochemical reactions that would lead to cell death, stops.
In order to prevent any damage to the cells during the freezing process, technicians use cryoprotective agents such as glycerol, ethylene glycol, sucrose, dimethyl sulfoxide (DMSO) and propylene glycol.
Once the cells are cryopreserved, it is believed they can be stored indefinitely for future use.
Common cryopreservation procedures
The three most common cryopreservation procedures are for eggs, sperm and embryos.
Egg freezing and banking
Before an egg freezing procedure, a woman first undergoes 10 to 12 days of hormone therapy. These hormones stimulate her ovaries and allow a doctor to collect multiple eggs during the egg retrieval procedure.
During an egg retrieval, the woman is placed under anesthesia while a physician collects the eggs using a long needle inserted through the woman’s vagina. The actual procedure takes only a few minutes, and many women resume normal activity within a day.
Frozen eggs are banked, or stored, until a woman elects to have them thawed for an in vitro fertilization (IVF) cycle. A doctor can fertilize thawed eggs in a lab using a partner’s or donor’s sperm and then transfer the resulting embryos to the woman’s or a gestational carrier’s uterus.
Embryo freezing and banking
Embryo freezing involves the same steps as egg freezing. However, in embryo cryopreservation a woman’s eggs are fertilized in a lab, then after several days of maturation, the eggs become embryos, or fertilized eggs, and are ready to be cryopreserved for use in future IVF cycles.
Did you know that many fertility clinics charge $1,200-1,800 for the freezing and storage of embryos?
At the Servy Massey Fertility Institute, cryopreservation and six months of embryo storage cost $910.
Sperm freezing and banking
Sperm cryopreservation is the least costly and invasive of all cryopreservation treatments. Since men’s ejaculate contains millions of sperm, a man does not typically need to undergo any special preparations before he provides a semen sample.
However, if a man has a low sperm count or male infertility, a doctor may perform a surgical procedure to remove enough sperm for sperm banking. Once the semen is collected, it is frozen until the man chooses to use the sperm for an advanced reproductive treatment, such as IVF or intrauterine insemination (IUI).
When is cryopreservation used?
Elective egg freezing
While men’s bodies continually create new sperm, women are born with all of the eggs they will ever produce. Once women begin puberty, they begin losing their eggs as part of their menstrual cycle. Over time, women’s eggs decrease not only in quantity but also in quality.
After the age of 35 it becomes more difficult for a woman to get pregnant without reproductive assistance. Women who freeze their eggs when they are in their 20s and early 30s have a better chance of getting pregnant later in life using their own eggs in combination with assisted reproductive treatments.
While cryopreservation does not guarantee that a woman will be able to get pregnant when she is ready, it is a proactive measure that can provide a woman with more family-building options after her eggs would typically no longer be viable.
Fertility preservation for transgender men and women
Both hormone therapy and sex reassignment surgery, which may involve the removal of reproductive organs, can affect a transgender man’s or woman’s ability to have biological children. If a transgender person hopes to begin a family after transitioning, he or she may choose to undergo fertility preservation.
Much like other forms of fertility preservation, transgender fertility preservation generally involves cryopreserving a person’s sperm, eggs or embryos. Cryopreserved sperm, eggs or embryos can then be used in IVF and other assisted reproductive treatments.
Concerned about future fertility? Find out if you are a candidate for cryopreservation services.
Fertility preservation before cancer treatments
Fertility preservation can help men and women overcome infertility that may come with disease diagnoses – mainly cancer. Individuals suffering from autoimmune diseases, such as lupus, Turner syndrome and galactosemia, may also benefit from fertility preservation efforts.
Cancer treatments, including radiation, can decrease a woman’s ovarian reserve, or the number of eggs in her ovaries. Radiation can also be harmful to a man’s sperm count and damage reproductive organs, depending on the location of the cancer.
There are several treatment options that may help preserve fertility before and after cancer treatments, including egg, sperm and reproductive tissue cryopreservation. In cases where a woman is no longer able to carry a child after cancer treatments, she has the option of using a gestational carrier or surrogate along with other fertility treatments.
IVF and other advanced fertility treatments
Egg freezing, embryo freezing and sperm freezing have become common procedures during many advanced fertility treatments, including IVF. For instance, men who cannot be present on the day of their IVF partner’s egg collection may choose to have their sperm cryopreserved until the retrieval date.
Doctors may also freeze eggs and embryos as part of the IVF process. These eggs may be from the mother or they may be donor eggs, collected in advance of an IVF cycle. The use of frozen eggs can provide more flexibility in timing IVF egg retrieval and implantation procedures.
During an IVF cycle, a doctor typically transfers one or two fresh embryos into a woman’s uterus. After the transfer of fresh embryos, individuals can elect to cryopreserve remaining embryos. People can then save these embryos for a later IVF cycle or donate their embryos to other individuals or couples undergoing fertility treatments.
Sometimes medical complications during an IVF cycle, including ovarian hyperstimulation syndrome (when the ovaries become abnormally swollen from fertility medications), may cause a doctor to cancel a fresh embryo transfer. The doctor can then freeze the embryo and perform a frozen embryo transfer once the risk to the woman’s health has passed.