What Is Egg Quality?

Egg quality refers to an egg’s genetic health and its ability to mature, be fertilized, and develop into a healthy embryo.

Key Factors Influencing Egg Quality:

• Age: The most significant factor. Egg quality declines with age, especially after 35.

• Hormonal balance

• Lifestyle factors: Smoking, alcohol, poor nutrition, and stress

• Underlying health conditions: Like PCOS or endometriosis

Poor egg quality increases the risk of chromosomal abnormalities, which can lead to:

• Failed fertilization

• Poor embryo development

• Miscarriage

What Is Embryo Quality?

Embryo quality is determined by how well an embryo develops after fertilization. It’s typically assessed by:

• Morphology (appearance) under a microscope

• Rate of development (how quickly it reaches stages like blastocyst)

• Genetic testing (like PGT-A, which checks for chromosomal normality)

While embryo quality depends heavily on egg quality, it also relies on sperm quality and lab conditions during embryo culture.

So, Which Matters More—Egg or Embryo?

The truth is: both matter, but egg quality is the foundation of embryo quality. A high-quality egg is more likely to result in a chromosomally normal embryo—one of the most important predictors of IVF success.

However, even a perfect-looking embryo can be genetically abnormal, which is why many clinics now offer preimplantation genetic testing (PGT) to increase the chances of choosing a viable embryo.

Why Embryo Quality Still Counts

Even with good egg quality, embryos can fail to implant or develop correctly. High embryo quality improves:

• Implantation rates

• Pregnancy success

• Lower miscarriage risk

Embryo grading (while not foolproof) helps doctors select the best embryos for transfer or freezing.

Can You Improve Egg or Embryo Quality?

While you can’t reverse age-related decline, you can support egg and embryo health by:

• Starting IVF earlier, if possible

• Taking prenatal vitamins (especially CoQ10 and folic acid)

• Maintaining a healthy lifestyle—eat nutrient-rich foods, exercise, avoid smoking/alcohol

• Managing stress

• Considering supplements (under medical guidance)

In some cases, donor eggs or donor embryos may be recommended if quality is a major barrier to success.

Takeaway: It’s All Connected

Egg quality has a direct impact on embryo quality, but both need to be optimal for the best chance at a healthy pregnancy through IVF. Working closely with your fertility team to monitor and support both can make a meaningful difference.