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3 Different Types of Embryos [And Their IVF Success Rates]

KEY POINTS:

Choosing the right embryo can make all the difference when you’re trying to grow your family through in vitro fertilization (IVF). With so much riding on each transfer, it’s only natural to want the best chance of success.

Genetic testing identifies three main types of embryos: euploid, aneuploid and mosaic. Each one offers different odds of success, and understanding these differences can help you make informed decisions moving forward.

In this article, we’ll go over embryo testing success rates and explain how genetic testing fits into the IVF process. If you’re looking for more information, you can learn more about your options after creating viable embryos.

The Success Rate of Genetically Tested Embryos

Preimplantation genetic testing for aneuploidy (PGT-A), formerly known as preimplantation genetic screening (PGS), helps identify which embryos are most likely to result in pregnancy. PGT-A checks for chromosomal abnormalities and allows you to prioritize the healthiest embryos for transfer. This can significantly increase your genetically tested embryos success rate.

You can learn about surrogacy with frozen embryos if you’re still in the embryo creation process, or contact us today for more information. If you already have embryos, we can match you with a surrogate quickly.

Below, we’ll break down the success rates for euploid, aneuploid and mosaic embryos to give you a better idea of what to expect.

Euploid Embryo Success Rate

A euploid or normal embryo has the correct number of chromosomes, giving it the highest chance of resulting in a healthy pregnancy. One study reports that the live birth rate for a euploid embryo is 64.8% on the first transfer.

If you have this type of embryo available, it should always be your first choice for transfer. You’re more likely to experience IVF success with a euploid embryo. Because euploid embryo transfer success rates give you the best path forward, they are especially important if you’re navigating concerns like maternal age or embryo quality.

Aneuploid Embryo Success Rate

An aneuploid embryo has an abnormal number of chromosomes, which is why it’s also called an abnormal embryo. The abnormalities can vary between embryos. For instance, a monosomy is missing one chromosome, while a triploidy has an extra set.

Unfortunately, abnormal embryo success rates are very low. Research shows that aneuploid embryos have an 86.3% chance of miscarriage and result in a healthy baby less than 2% of the time. Because the success rate of transferring abnormal embryos is so low, many clinics choose not to transfer them.

In addition to the emotional toll of miscarriage, aneuploid embryos can pose a risk to surrogates. This makes them a less viable option in surrogacy journeys. If you don’t have any euploid embryos, your fertility team may recommend other paths forward, such as creating more embryos through IVF or using donor eggs or sperm.

Mosaic Embryo Success Rate

A mosaic embryo contains both normal and abnormal cells, making it a mix of healthy and unhealthy genetic material. These embryos are classified as either low-level or high-level mosaics based on the percentage of abnormal cells. Studies show that mosaic embryos with no more than 50% abnormal cells have a live birth rate of 46.6%.

Many fertility experts recommend transferring mosaic embryos if no euploid ones are available. While mosaic embryo transfer success isn’t quite as high as euploid embryos, they still offer a reasonable chance of having a healthy baby. If you’re in this situation, your fertility team can guide you through the risks and benefits of transferring a mosaic embryo.

How PGT-A Testing Works

PGT-A testing screens embryos for chromosomal abnormalities before they are transferred. This test is an optional step, but many people choose to invest in it to improve their chances of a successful transfer. By identifying the healthiest embryos, PGT-A can help reduce the risk of miscarriage and unsuccessful transfers.

Here’s what the step-by-step process looks like:

  • Step 1: Embryo Creation

    PGT-A testing takes place at the blastocyst stage, which is typically day five or six of development.

  • Step 2: Biopsy

    Your clinic will remove a small number of cells from each embryo.

  • Step 3: Freezing

    It can take a few days to test the cells, so your embryos will be frozen to preserve them.

  • Step 4: Genetic Analysis

    The embryos will be analyzed for chromosomal abnormalities.

  • Step 5: Embryo Transfer

    Once you have the results, you can decide which embryos to transfer based on their health and viability.

    PGT-A testing isn’t just useful for traditional IVF — it can also play an essential role in surrogacy. Many surrogacy agencies require intended parents to use genetically tested embryos to protect both the surrogate and the baby. With PGT-A, you can feel more confident about moving forward with your surrogacy journey.

    3 Factors That Could Impact Embryo Testing Success Rates

    While PGT-A can boost your odds, several factors can still affect the outcome. Your embryo testing success rate may look different depending on various factors, such as:

    • Embryo Quality

      High-quality embryos are more likely to implant and result in a healthy pregnancy. Quality is judged by two factors: morphology (the embryo’s size, shape and cell structure) and developmental stage (how far it has progressed).

    • Maternal Age

      Your age impacts the quality and quantity of your eggs, with fertility generally declining after age 35. For instance, PGT-A normal embryo success rates may be lower if you’re over 40.

    • Uterine Health

      A healthy uterus is crucial for successful implantation and a smooth pregnancy. It helps create an optimal environment for the embryo to attach and grow.

      Interested in Embryo Genetic Testing for Surrogacy?

      Genetic testing is often required in surrogacy to ensure the health and safety of both the surrogate and the baby. This reduces the risk of complications and increases the likelihood of a successful pregnancy.

      If you’re considering surrogacy, understanding genetic testing requirements can help you prepare for the journey ahead. To learn more about the requirements for surrogacy, check out our other article or fill out our contact form today. We’re here to help you take the next step toward growing your family.

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