Poor Embryo Quality IVF Success

You can become a parent whether you have high or low quality embryos. Learn about poor quality embryo success rates and what to expect here.

IVF specialists promote embryo grading to determine which embryos to transfer. This grading helps embryologists select the highest quality embryos for transfer, increasing the likelihood of implantation and a successful pregnancy.  

It’s important to know that while embryo grading is important, poor-quality embryo success rates don’t necessarily mean that there’s no chance of pregnancy.

If you are not yet working with a fertility clinic, we can connect you with one. If you have embryos that are ready for transfer, fill out our simple form to take the next step toward parenthood.

What is Embryo Grading?

When embryos are created, fertility clinics check embryo development at different points to help determine which embryos are most likely to become viable pregnancies. Think of it as a quality check for embryos, where each one is carefully examined under a microscope.  When medical specialists observe embryos, the grading system helps organize the embryos from most likely and least likely to thrive.

Poor Embryo Quality: IVF Success Rates

There are plenty of IVF success stories with poor quality embryos. A lower poor-quality embryo success rate does not necessarily mean that an embryo won’t result in a clinical pregnancy and live birth. Instead, it may just mean that the embryo is not growing and developing as quickly as other embryos.  

It is not uncommon for families to have an unsuccessful round of IVF with a higher-graded embryo, then a successful round of IVF with a lower-graded embryo. Lower-quality embryos can have a chance of becoming a healthy pregnancy.

For more information about your embryos, talking to your fertility doctor can help you get more insight into your situation. If you have created embryos and they’ve already been graded or you are in the process, fill out our form. We can connect you with a surrogate who will begin preparing for the embryo transfer once you have completed the legal process.

When Are Embryos Graded?

Fertility clinics often transfer embryos on day 3 or day 5, and so on these days, embryo development is checked and the embryos that are determined to be of better quality are transferred first.

Embryo assessment is different depending on which day the clinic grades the embryo.

Day 3 Embryos [Cleavage Stage]

Day 3 embryos are graded based on cell number as well as the appearance of the cells:

  • Cell Number: Evidence shows that when embryos have 8 cells on day three, there is a higher live birth rate, while lower numbers of cells have a lower live birth rate.
  • Cell Appearance: Grading for cell appearance is more subjective and can depend on the fertility clinic or individual provider. Fertility specialists look for abnormal cells or structure and check for equal size and shape of cells.

Day 5 Embryos [Blastocyst Stage]

Grading embryos on day 5 is more nuanced than on day 3, and day 5 grading is less consistent across fertility clinics. By day 5, the embryo is called a blastocyst and fertility clinics look for:

  • Quality of ICM (Inner Cell Mass): The inner cells become the fetus, and medical specialists check the appearance of the inner cells for development and abnormalities.
  • Quality of TE (trophectoderm epithelium): The trophectoderm epithelium will develop the placenta and other necessary tissues that are needed to support pregnancy, which is why these cells are checked.
  • Blastocyst Expansion: As the embryo grows, a fluid-filled cavity forms (called a blastocoel). More developed or larger blastocoels can be used as markers of good-quality embryos.


Can average quality embryos become healthy babies?

Average-quality embryos can become healthy babies. Embryo quality does not necessarily mean that a child that develops from the embryo will be unhealthy. Using a higher-quality embryo is meant to increase the likelihood that a pregnancy will occur and that the pregnancy will result in a live birth.

What is a failed IVF embryo quality?

Poor quality embryos are embryos that develop abnormally or that do not develop on pace with expected development. Some embryos may fail to show healthy development and may be unable to be transferred.

Can a poor-quality egg implant?

Eggs and embryos graded as “poor” quality can still implant and become pregnancies, although the likelihood of poor-quality eggs implanting is lower.

What is the success rate of CB embryos?

CB embryos have a lower success rate than AA embryos, but the overall success rate of CB  embryos depends on the number determination that goes along with the letters. Higher numbers correspond to higher rates of successful pregnancy.

If you have poor quality embryos or do not have embryos, you can reach out here and our surrogacy professionals can help you find a path towards building your family successfully.