Are Frozen Embryos 100% Guaranteed?
Freezing embryos are a common part of the IVF process. During the first cycle, the clinic produces several embryos, many of which are frozen for later use. Frozen embryos aren’t guaranteed to work, and there are a few reasons why these may fail. To reduce failure rates, the clinic may suggest PGT or preimplantation genetic testing.
It’s time for FET
A frozen embryo transfer, or FET, is the process of thawing embryos to transfer one more into the womb. Before FET happens, the uterine lining must be prepared through hormone medication done at the right time. FET benefits women or couples who are unsuccessful in the first cycle. FET also comes in handy if someone wants to have a child at a later stage in life. Failure rates can be classified into 3 main categories.
1. It’s down to the embryo quality
Unfortunately, embryo creation is not a perfect process, even during a natural pregnancy. Embryos need the correct number of chromosomes every time, which does not happen as often as expected. This is known as embryonic aneuploidy and is the number one reason for embryo failure during transfer. Age is one of the most common reasons for failed embryos. With age, women may produce more unsuccessful embryos and often need multiple IVF cycles.
2. The timing’s not right
For FET, the timing has to be just right. The doctor transfers the embryo at a specific time during ovulation. In some cases, if a woman has a natural, healthy ovulation cycle, the transfer can happen without medication. However, in most cases, ovulation is initiated by hormone medication. The medicine reduces the chances of the embryo transferring at the wrong time. Even with a perfectly healthy embryo, an inaccurate timeline can create a failed embryo transfer.
3. An unprepared uterine lining
During the window of implantation, the uterus is getting ready to accept the embryo. In some cases, complications with the uterus can cause the embryo transfer to fail. For instance, a thin endometrial lining can be too thin. Now, a thin uterine lining does not necessarily mean pregnancy will not happen. However, the chances of a full-term pregnancy reduce significantly. Other reasons include uterine polyps, fibroids, excess fluid, or infections.
Time to consider PGT
Careful timing, monitoring, and addressing uterine conditions can help. For failed embryos, the clinic can turn to PGT. Preimplantation genetic testing worked well for preventing miscarriages and failed IVF cycles. The process tests for genetic anomalies that can be causing the failure. That way, the doctor can transfer the healthiest embryo available instead of being unsure if there is embryonic aneuploidy.
What happens during PGT?
A few weeks before implantation, the clinic will thaw the patient’s available embryos. In most cases, 98% of the embryos survive the thawing process. From there, an embryologist removes a sample from each embryo for testing. The embryos must have a healthy number of cells to qualify for the biopsy. At this point, the clinic can also identify if assisted hatching is needed to help with IVF. The embryos are re-frozen, and the biopsies head to the lab for testing, with the results taking a week.
Does it work?
Both doctor and patient go through the PGT results. From there, IVF can proceed with the best embryos available. Doctors have seen promising results with embryo transfers using PGT. Recent studies show that women are twice as likely to have a live birth after testing. If an IVF cycle failed, PGT could help.
There is still hope
Failure of a frozen embryo can be stressful and emotionally crushing. These emotions can make the IVF process seem hopeless, but failed embryos aren’t always the patient’s fault. To rule out low-quality embryos, PGT can help. Make sure to communicate constantly with the reproductive endocrinologist. From there, both patient and doctor can develop a game plan to improve the success of IVF.