The Facts About Egg Quality

Egg Quality

Improving egg quality is vital if you’ve been struggling to get pregnant and:

  • You’re over 35.
  • Your cycle is getting shorter.
  • You’ve got low AMH.
  • You have Diminished Ovarian Reserve (DOR).
  • You’ve had unsuccessful IVF.

Egg Quality Facts

  • Women under 35 have up to a quarter of eggs with chromosomal abnormalities.
  • Women over 40 can have between 50% to 80% of eggs with chromosomal abnormalities.
  • 10-15% of recognised pregnancies end up in miscarriage.
  • 70% of natural pregnancies end up in miscarriage.
  • 70% of repeated implantation failure in IVF is due to abnormal embryos.
  • Poor quality eggs with chromosomal abnormalities is the main reason for miscarriage, failed IVF and delayed pregnancy.

How Chromosomal Abnormalities Happen

  • Eggs lie dormant until 3 months before ovulation when they go through a maturation process called meiosis. 
  • During meiosis, an egg cell divides and reduces the number of chromosomes. 
  • In this process, chromosomes cross over and exchange genetic material to create genetic variation.
  • Most of the chromosomal errors occur 3 months before ovulation when either chromosome don’t separate and pair up again properly in meiosis. Or chromosomes break, become inverted, get deleted due to chemicals and viruses.
  • When there is a chromosomal abnormality, the body recognises that pregnancy isn’t viable and will miscarry. 
  • Occasionally the body will not recognise chromosomal errors and the pregnancy continues. Downs Syndrome, 3 copies of chromosome 21, instead of 2.

What Some Doctors Don’t Know About Egg Quality

  • It used to be thought that eggs gradually get chromosomal abnormalities from the age of 30. However, we now know that most chromosomal abnormalities happen in the 3 months before you ovulate.
  • This means that if you change the conditions for the egg as it goes through meiosis, then you can change the chances of errors and increase the chances of producing a healthy viable egg.

Egg Energy

  • It takes a lot of energy for an egg to mature and produce the correct number of chromosomes.
  • Mitochondria are like a battery in the cell that creates the energy the cell needs to perform functions.
  • Over time mitochondria get damaged and don’t produce enough energy. The problem with mitochondria not working well is that chromosomal abnormalities can occur.
  • One of the solutions to producing eggs with the correct chromosomes is to protect mitochondria from damage and help them to work better.
  • Recent scientific research shows that eggs with chromosomal abnormalities can be influenced by nutrition and lifestyle factors.
  • Studies have shown that there is a wide range of the number of chromosomal abnormalities in women of the same age, which shows that age is not the problem.

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All my best,

Rachel xx

Rachel Bolton BSc (Hons), Lic. Ac., Lic. Tui Na.

I empower women to see themselves as Fertility Heroes and help them to optimise their fertility, get pregnant and have healthy babies.  


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