For many, the process of IVF can be a challenging experience. It takes time, sometimes several rounds or cycles of IVF before a couple is able to successfully get pregnant. Among the various tests, examinations, and hormone shots, you will be given the option to decide whether you wish to proceed with a fresh embryo transfer or frozen embryo transfer.
While the decision is completely yours to take, your clinician may also make a recommendation depending on your health condition and which type of embryo transfer may possibly get you a more successful outcome.
What is the Frozen Embryo Transfer?
Generally, the retrieved eggs are fertilized and developed into embryos under laboratory conditions.
Just as it sounds, a ‘fresh’ embryo transfer typically implies that the embryo will not be in a frozen state prior to transferring it to the uterus. Generally, the embryos are monitored for a period of 5 days before the transfer takes place.
A ‘frozen embryo transfer involves the embryo being frozen post retrieval during a specific developmental stage. A waiting period ensues before the frozen embryos are removed from a state of cryopreservation on the morning when the transfer is scheduled to take place. The embryo is transferred into the uterus in a more physiologic state.
Why is the Frozen Embryo Technique Successful?
Frozen embryo transfers have been done for many years and have become very popular today because freezing technology has improved drastically in the past decade. Now, we can freeze an embryo, and later on, take it out of the freezer and thaw. The embryo will be at the same quality it was when it was initially fresh. This allows the uterus to recover from all these stimulations of the IVF cycle and enhances the implantation rates in some women.
What Is the Process of Frozen Embryo Transfer?
The process of frozen embryo transfer starts with the beginning of a new menstrual period cycle. Generally, the patient control pills for two weeks to thin the lining of the uterus. Then it takes about 10 to 12 days of oral estrogen tablets to rebuild the lining. By this time, the ovulation period will be starting. Then the patient is given a five-day course of progesterone, following which the embryo is transferred. Since the embryos are frozen at about five days of growth, so the synchronization of the lining with the actual transfer of the embryo into the uterine cavity is important.
Why Should You Opt for A Frozen Embryo Transfer?
There are two possibilities for transferring embryos during IVF. You can either choose to select a fresh embryo transfer or go with frozen embryos instead.
In a fresh transfer, the embryos are placed in the uterus within five days of the egg retrieval without being frozen. The embryo transfer can be deferred to a later time, however, by freezing the embryos.
There are several advantages to a deferred transfer.
- Most importantly, studies now show that the chance that the embryos will implant into the uterine lining is improved by waiting until later in some women.
- Additionally, frozen embryo transfer helps avoid a severe complication of IVF treatment called ovarian hyperstimulation syndrome in women at risk such as those having PCOS.
- Lastly, frozen embryo transfer allows genetic testing of the embryos to be performed, which improves the chance of pregnancy and reduces the risk for miscarriage.
General reasons for proceeding with frozen embryo transfers may be:
- You have extra embryos to preserve which means if one cycle of fresh transfer fails you have a backup on standby
- You may wish to have another pregnancy in the future
- You have the flu or other medical conditions that make fresh embryo transfer impossible
- You may be using an embryo donor
Frozen vs. Fresh Embryo Transfer: Which is Better?
The fundamental question is this – if you are doing IVF, is it better to put the embryos into the uterus right away or freeze the embryos and put them back in later?
The most commonly used option was to pursue a fresh embryo transfer since pregnancy success rates with frozen embryos were not really encouraging. However, over the years, freezing technology has been enhanced which are led to increased success rates using frozen embryo transfers.
In 2016, at a European Society of Human Reproduction and Embryology (ASHRAE) conference, Dr Karen Hunter Cohn presented a study in which she examined more than 16,000 IVF treatments performed at 12 fertility centers. After the match was done against several different variables, the learnings and analysis highlighted insights, for example, that in certain groups, freezing all of the embryos followed by deferring embryo transfer produced more successful pregnancies in comparison to a fresh embryo transfer.
Among the groups that showed improvement were:
a) Women over 35 years old. 46% of these couples became pregnant using deferred transfer compared to 33% who became pregnant with a fresh transfer.
b) There was also a benefit found in patients with elevated hormone progesterone levels before egg retrieval such as women with PCOS. This was evident irrespective of whether the patients were younger or older.
Due to this and other studies, there is an ongoing debate among fertility specialists on whether other patients may gain from the same ‘freeze-all approach.
So, if you are thinking of undergoing frozen embryo transfer, make sure to get your endometrial lining nice and sticky to optimize your gestational environment, thereby increasing the chance of you getting pregnant.
If you still have questions, why not get them clarified with Dr Vyjayanthi, an experienced Fertility Specialist in Hyderabad. Having performed over 10,000 IVF cycles, Dr. Vyjayanthi and her team of experienced fertility specialists at MotherToBe have the necessary training and expertise to carry our frozen embryo transfers if indicated for your medical condition that will ensure that the success rate of your IVF cycle is optimized to the maximum.
Let MotherToBe be a part of your pregnancy experience that is filled with hope and happiness and with you are becoming loving parents to your bundle of joy.