Embryo Freezing
Author : Professor Eman Zein
• Updated at: Jun 09, 2024 •
Embryo cryopreservation means preserving an embryo at very low temperatures (well below zero) which is why some people refer to it as embryo freezing, this is process is done to preserve embryos for later use after having done an Assisted Reproductive Technology (ART) treatment like IVF or ICSI.
The procedure of Embryo Freezing
To start an ART procedure like IVF/ICSI a couple is required to go through a thorough history taking to determine all the variables that could affect a successful completion of the IVF/ICSI procedure. The female partner undergoes a physical examination including a vaginal ultrasound a blood test including a hormonal profile is withdrawn and a semen analysis is done for the male partner to see if he requires further examination with all of this done the induction medication is given on a specific time. During the phase of ovulation stimulation, the female partner undergoes several vaginal ultrasounds and blood tests to monitor the ovulation. When the oocytes are mature enough to be collected a trigger is given on a specific time and again on a specific time the oocytes (eggs) are collected. They are then left to be fertilized with sperm in a test-tube in IVF or injected under the microscope with sperm cells in ICSI. The formed zygotes are them put in an incubator for fertilization and division. Embryos then formed can either be transferred or frozen or both!
Please feel free to call our call center to know more about all our cryopreservation services and options.
When is embryo freezing done?
- Embryo freezing is considered when:
- A couple isn’t ready to have children just yet but definitely want to have children together in the future.
- After an IVF/ICSI trial where extra embryos which will not be transferred are frozen.
- Uterine problems which could affect implantation and pregnancy rates, so embryo cryopreservation (embryo freezing) is done until that problem is fixed
- Internal issues like uncontrolled blood sugar or thyroid issues where embryo freezing is done until the female’s overall health is better.
- Undergoing treatment that could affect a couple’s fertility in the future like cancer treatments.
Couples sometime choose to do embryo freezing instead of oocyte freezing because the percentage of embryos that get affected in the process of freezing and thawing are less than those of frozen oocytes.
Problems with freezing Embryos
Embryo cryopreservation (embryo freezing) is a procedure that as mentioned is done to preserve embryos for future use. A concern of many couples that have done embryo freezing or are considering it is problems with frozen embryos occurring. If embryos are frozen using the vitrification method used in Bedaya Hospital over 90% of the embryos remain healthy and well for transfer. Embryo quality after freezing and thawing them highly depends on the quality and the expertise of the staff and laboratory where the process is done! Embryo freezing at Bedaya Hospital over the past 2 decades has shown some of the best regional and international success rates.
Embryo freezing success rates
The definition of embryo freezing success rates can differ according to what you consider “success” Is success the embryo remaining its quality and surviving the vitrification/thawing process? Is it resulting in implantation? Resulting in a pregnancy that surpasses the first trimester or is it transferring and having a healthy baby after embryo cryopreservation/Embryo freezing? The HFEA (Human Fertilization and Embryology Authority) Embryo freezing success rates is the percentage of frozen embryos transferred resulting in live birth. This percentage of course depends on several variables of which of course the maternal age at the time of egg collection and fertilization is a major factor but overall, they are around 50-60%.
Frozen versus fresh embryo transfer
Patients always wonder and express their concerns about frozen versus fresh embryo transfer. Are the success rates of one better than the other? The answer is usually like anything that concerns “people” that it depends on several variables! Usually, the success rates of undergoing a fresh or frozen embryo transfer are almost equal however research has shown that a transfer after embryo freezing is usually better for the following patients:
Patients with Polycystic Ovary Syndrome (PCOS), women with regular periods and regular levels of gonadotrophin releasing hormones and women that do an embryo transfer of embryos that were frozen when she was at a younger age.
How long can embryos be frozen?
We have discussed that one of the most important variables for embryo freezing success rates is the maternal age at the time of the ovum pickup and fertilization. This results in the obvious question how long can embryos be frozen? Frozen embryos stored and monitored through strict laboratory regulations can be stored for up to 10 years. Embryo freezing at Bedaya Hospital has even showed great success rates for embryos frozen more than 10 years ago!
Embryo Freezing temperatures
The best embryo freezing success rates are found in well-structured laboratories with constant monitoring and calibration which we offer you at Bedaya Hospital. There are several daily checks and a safety management network in place to keep the temperatures in our embryo tanks between -30 to -40 degrees Celsius.
Is a frozen embryo a baby?
When the DNA of two parents meet during fertilization (also called conception) a zygote is formed after a couple of days of cell division it is called a blastocyst and then an embryo is formed. In humans an embryo isn’t considered a fetus or “baby” until 9 weeks after conception or 11 weeks after the first day of your Last Menstrual Period (LMP). So no when we freeze your embryo, we are not freezing a baby!
