The embryo banking, or freezing process is where a patient or couple chooses to go through the first steps of the IVF process: preparation, ovarian stimulation, egg retrieval, and fertilization with partner sperm or donor sperm but instead of transferring the embryos they are frozen and saved for later. Embryo banking is a very similar process to egg freezing except instead of freezing unfertilized eggs, we will create embryos in the lab and then freeze those. This also involves a 10-14 day cycle in which your ovaries are stimulated to grow mature eggs. The eggs are then removed through a very short out-patient procedure. The eggs are fertilized with predetermined sperm to create embryos, and frozen for your future use.
All couples who are looking to genetically test their embryos must freeze them first. Embryo freezing has heightened in popularity with increased use of genetic testing. The embryologist will take a biopsy of the embryo and send it to our genetic partner lab for testing, but we will only transfer healthy embryos. The first pregnancies born from embryo freezing occured in the 1980s. Embryo freezing for long-term fertility preservation, often referred to as ’embryo banking,’ has experienced a notable surge in usage in recent times
There have been numerous studies showing no health differences of babies born from fresh embryos or frozen embryos. In fact, some studies actually show pregnancy rates are higher from frozen embryos instead of fresh embryos.
What is the difference between egg and embryo freezing?
There are important considerations to take into account when deciding whether to choose embryo banking or egg freezing, mainly surrounding the use of sperm. Embryo freezing is only available to patients who have already selected their sperm source. Embryos can not be “unfertilized.” Embryos legally belong to two patients unless an egg or sperm donor is used.
If a couple undergoes embryo freezing they must agree to embryo disposition. Embryo disposition is similar to an advanced directive, which is used in the event of death, divorce, or embryo abandonment to determine what the lab should do with the embryos.
Because eggs are slightly more delicate than embryos, they are marginally more challenging to freeze and thaw. Embryo freezing is more of an established technique. However, with modern technology and techniques used at Mate clinics, the likelihood of egg and embryo survival are on par with each other.
Why do people freeze embryos and is it safe?
Embryo freezing for fertility preservation is used to increase the chance that future IVF, if needed, will be as successful as possible. Short term embryo freezing is often done to facilitate genetic embryo testing. This testing may optimize embryo transfer success rates in some patients. The embryos are kept frozen in storage until they are needed and if a patient needs to use the embryos for IVF then the embryo is thawed during a frozen embryo transfer.
Although there are still many studies that are being done, the majority of large studies show that embryo freezing has minor, not major risks. It is important to thoroughly read and understand your consent forms before starting treatment and discuss any questions you may have with your Mate team.
What are the first few steps of embryo freezing?
Embryo freezing is the first few steps of the IVF process with a delay of embryo transfer. In-vivo means “in the body” while in-vitro means “in glass” in latin. In-vitro fertilization (IVF) is an overarching term that describes reproductive technology which allows for fertilization outside of the body.
Preparation & Stimulation: Patients need to emotionally, socially and physically prepare to start stimulation. Some protocols require medications during preparation (priming) and some patients may choose to optimize their lifestyle during this time. During Ovarian stimulation, patients take medications that stimulate the simultaneous production of multiple eggs in the ovaries. This often involves 2-3 injections each day, using very small needles, or a combination of oral medications and injections for approximately 9-14 days. During this time the growth of the eggs is monitored by vaginal ultrasounds and hormonal blood tests.
Egg Retrieval: An egg retrieval is a minor surgical procedure where the eggs are retrieved from the ovaries using a long thin aspiration needle and suction. Anesthesia is given to avoid pain and discomfort, then the needle is placed through the vagina under ultrasound guidance, directly into each ovary. This procedure typically takes 15-30 minutes and is an outpatient procedure, meaning patients typically do not need to stay in the hospital overnight.
What are the next few steps of embryo banking?
Recovery: The recovery after an egg retrieval varies person to person. Most patients experience vaginal spotting, mild cramping, bloating, and constipation for a few days after the procedure. Pain medication and over the counter stool softener/laxatives may be needed to avoid discomfort. Typically the more eggs, the more substantial the side effects, however most patients are able to return to activities of daily living within 1-2 days and full activity comfortably within 2 weeks.
Fertilization: Once eggs are retrieved they can be fertilized in the lab with sperm. There are two ways that fertilization occurs in the lab: conventional IVF and intracytoplasmic sperm injection (ICSI). In IVF, a number of sperm are placed around each egg. In ICSI, the eggs are prepared by taking off the surrounding cells and single normal appearing, motile sperms are selected and injected into each egg. In some labs, ICSI has been shown to optimize for successful fertilization.
Embryo Preparation: An egg and sperm that successfully undergo fertilization is called an embryo. Embryo(s) can be biopsy tested if desired. Embryos are then frozen using liquid nitrogen and are thawed if/when patients desire to use them to attempt to conceive using a frozen embryo transfer cycle.