If you’ve been trying to build your family through assisted reproductive technology, you may be considering freezing your embryos for IVF or surrogacy, or have already done so.
An important component of the IVF process that can optimize your family-building journey even further, is having your frozen embryos genetically tested.
Genetic testing on frozen embryos can help you understand the health and viability of your embryos, which can help your clinic select embryos for transfer that have the highest chance of becoming a pregnancy. Genetic testing your embryos before implantation is crucial for many parents undergoing in-vitro fertilization (IVF) and those considering surrogacy.
We’re here to help you understand genetically testing frozen embryos, explaining the process, the timing for transferring tested embryos, the success rates associated with preimplantation genetic testing (PGT) and the different types of genetic tests available.
We can help you find a surrogate when you’re ready.Have Embryos Created?
Can Frozen Embryos Be Genetically Tested?
Yes, frozen embryos can be genetically tested, whether they have been stored from a previous cycle or were created specifically for surrogacy. This process, known as preimplantation genetic testing (PGT), allows you to gain insights into the genetic health of your embryos before proceeding with an embryo transfer.
Chromosomal abnormalities cause about 50-70% of all miscarriages.
Some couples are hesitant to undergo frozen embryo genetic testing because of the costs associated with PGT. Although PGT won’t prevent you from miscarrying, you can find comfort in genetic testing knowing that a genetic abnormality likely wasn’t the cause of a miscarriage.
Women over the age of 35 Those who want to selectively implant a single embryo to avoid the risk of a multiples pregnancy Those who have failed previous IVF cycles Those with a history of unexplained miscarriages Those with previous chromosomal abnormal pregnancies Couples with a single-gene disorder or sex-linked genetic disorder Couples who want to select the gender of their childCandidates for Genetic Testing on Frozen Embryos
Genetic Testing of Frozen Embryos Process [3 Steps]
Step 1: Thawing the Embryos
The first step in testing frozen embryos is to thaw them carefully. This is a delicate process that must be done under strict laboratory conditions to ensure the embryos' viability. Once thawed, a few cells are gently biopsied from each embryo.
Step 2: Performing Genetic Testing
The biopsied cells must come from the trophectoderm, or the cells destined to become the placenta rather from those that will become a fetus. These cells are then analyzed to detect genetic abnormalities or specific genetic conditions.
The two main types of genetic tests performed on embryos are:
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Preimplantation Genetic Screening (PGS): This test looks for chromosomal abnormalities, such as missing or extra chromosomes, which can lead to conditions like Down syndrome.
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Preimplantation Genetic Diagnosis (PGD): This test is used to identify specific genetic disorders that parents may be carriers of, such as cystic fibrosis or sickle cell anemia.
Step 3: Refreezing the Embryos
After the biopsy, the embryos are refrozen using a process called vitrification. Vitrification is a rapid freezing technique that helps preserve the embryos' viability for future use.
The time it takes to receive PGT results can vary, but it generally takes about one to two weeks. Once the results are available, you can discuss them with your fertility specialist to determine the best course of action.
Timing the Embryo Transfer
The easiest and best way to perform genetic testing on frozen embryos is about a month or more before you’re ready to begin the transfer process. The embryo transfer cannot occur until a surrogate has been matched and has undergone the necessary fertility medications to prepare her uterus.
One of the advantages of using frozen embryos is the flexibility it offers. Since the embryos are already frozen, the transfer can take place whenever you’re ready.
Success Rates of Genetic Testing on Frozen Embryos
Studies have shown that embryos that undergo PGT and are found to be genetically normal have higher success rates of implantation and healthy pregnancies. The survival rate of embryos after thawing and refreezing is also very high, making this a viable option for many parents.
An aneuploid embryo has an abnormal number of chromosomes, either missing or having extra chromosomes. Factors influencing aneuploidy include maternal age, genetic mutations and environmental factors. Common disorders resulting from aneuploidy include Down syndrome (trisomy 21), Edwards syndrome (trisomy 18), and Patau syndrome (trisomy 13). A euploid embryo has the correct number of chromosomes, 46 (23 pairs) in humans. Maternal age, overall health and genetic background can influence the likelihood of producing euploid embryos. Euploid embryo success rate is higher for implantation and live birth. They are generally selected for transfer to increase the chances of a healthy pregnancy. Mosaic embryos contain a mix of euploid and aneuploid cells. This means some cells have the correct number of chromosomes, while others do not. The mosaic embryo success rate fall between those of euploid and aneuploid embryos. While they can lead to healthy pregnancies, the outcomes are less predictable and there's a higher risk of complications.Success Rates of Genetically Tested Embryos [PGT-A]
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Genetic testing on frozen embryos can help you feel confident during your family-building journey. By understanding the genetic health of your embryos, you can increase your chances of a successful pregnancy and reduce the risk of genetic disorders. If you’re interested in learning more about how genetic testing can impact your IVF journey, read more about embryo transfer success rates and PGT.
With the flexibility that frozen embryos provide, you can plan your embryo transfer when you’re ready, ensuring the best possible outcome for your growing family.
If you have frozen embryos and want to explore surrogacy as a path to parenthood, then contact us online now or call us at 1-800-875-2229.