As you get older, the number and function of mitochondria in your eggs can decline. That can lower egg quality even if your overall health is good. Learning about mitochondria gives you a deeper understanding of what’s happening inside your body.
What Is Mitochondria?
Mitochondria are often called the “powerhouses” of cells because they produce adenosine triphosphate (ATP), the main energy source for cellular activities. These tiny, bean-shaped structures have a double membrane, and their inner folds help produce energy efficiently.Egg cells are the largest cells in your body and contain a high number of mitochondria to meet their significant energy demands. These structures are crucial for:
- Supporting the energy-intensive processes of egg maturation, fertilisation, and early embryo development.
- Makes sure eggs have enough energy to complete critical tasks, such as ovulation and chromosome segregation during meiosis. During this process, the egg removes half of its chromosomes by separating the pairs and keeping only one from each. It makes sure the egg ends up with the right amount of genetic material.
Mitochondria and Egg Quality
The health of your mitochondria has a direct effect on egg quality, which is important for conception. They supply the energy needed for eggs to mature and develop into healthy embryos. Their role includes:- ATP production: Each egg has a set number of mitochondria. These mitochondria make ATP, which is the energy the egg needs. This energy is important for fertilisation and for the embryo to start growing. After fertilisation, the number of mitochondria does not increase right away. This means the egg must already have enough energy stored to support early growth. Good-quality eggs are able to produce enough ATP to reach the blastocyst stage, which is an important step before implantation.
- Chromosome segregation: Proper mitochondrial function is needed for correct chromosome separation during meiosis. Insufficient energy can lead to errors and result in aneuploidy (abnormal chromosome numbers), which increases the risk of miscarriage.
- Maternal inheritance: Your egg’s mitochondria are the only ones passed on to your baby. After fertilisation, the sperm’s mitochondria are broken down through a process called mitophagy. It makes sure that your embryo inherits only your mitochondrial DNA (mtDNA). This maternal inheritance helps maintain consistent mitochondrial function in the embryo. But if your mitochondrial DNA has mutations, it can lead to a condition called heteroplasmy. This means more than one type of mtDNA is present in a cell, which may affect embryo development.
Mitochondrial DNA and Fertility
Mitochondrial DNA (mtDNA) is inherited exclusively from the mother. This special type of genetic material is important for how mitochondria function and directly affects egg quality:- Impact of mutations: Changes in mtDNA disrupt mitochondrial function and reduce ATP production. This affects the egg's ability to develop properly. These mutations are often associated with age-related infertility.
- Marker of egg quality: The presence of abnormal mtDNA can indicate lower egg quality and make it a potential marker for fertility challenges.
- Risk of developmental issues: mtDNA mutations in embryos can increase the risk of developmental disorders in the baby, particularly those from assisted reproductive technologies (ART).
Ageing and Mitochondrial Dysfunction
As you age, the quality and quantity of your eggs decline due to changes in mitochondrial function. This is a major factor in reduced fertility with advancing age. Effects of ageing on mitochondria include:- Reduced mitochondrial numbers: The number of mitochondria in your eggs decreases with age. This means lower ATP production and less energy for egg development.
- Increased oxidative stress: Mitochondria produce reactive oxygen species (ROS) as a by-product of ATP production. As you age, ROS levels increase and cause oxidative stress, which damages DNA and proteins. This further lowers egg quality.
- Higher aneuploidy rates: Poor mitochondrial function can affect the structure that separates chromosomes in the egg. This can lead to the wrong number of chromosomes (aneuploidy) and may increase the risk of miscarriage.
Strategies to Improve Mitochondrial Health
Improving mitochondrial function can help enhance egg quality and support your fertility. Some strategies to support mitochondrial health include:- Coenzyme Q10 (CoQ10) supplementation: CoQ10 is a key component of the mitochondrial energy production process. Its levels drop with age, so taking it as a supplement may help improve egg and embryo quality.
- Antioxidant-rich diet: Eating foods high in antioxidants, such as leafy greens, nuts, and fish, can reduce oxidative stress and protect mitochondria from damage.
- Regular exercise: Physical activity can increase the number of mitochondria in cells and enhance their function.
- Adequate sleep: Good-quality sleep is important for mitochondrial health as sleep deprivation can impair their function and cause DNA damage.
- Stress management: Long-term stress can harm mitochondria and egg quality. Techniques like meditation, breathing exercises, or gentle movement can help reduce these effects.
- Avoiding environmental toxins: Reducing exposure to pollutants, pesticides, and excessive heat by choosing organic foods and non-toxic cleaning products can protect mitochondrial health.
- Alpha-lipoic acid (ALA): This antioxidant supports mitochondrial energy production and protects against oxidative damage.
- Vitamin D: Optimal vitamin D levels are important for mitochondrial function, as low levels can reduce energy production in cells.
- Omega-3 fatty acids: Found in fish and supplements, omega-3s can help prevent ovarian ageing and improve egg quality.
Mitochondria play an important role in fertility by providing the energy your eggs need to grow, mature and support early embryo development. Their health directly affects your ability to conceive and maintain a healthy pregnancy. As you age, mitochondrial function can decline, and this may lower your fertility. If you're worried about conceiving, it’s always worth speaking with a qualified fertility specialist.
FAQs on The Hidden Reason Your Eggs May Not Be Healthy Enough
- How does mitochondrial health affect my chances of getting pregnant?
Healthy mitochondria help your eggs develop properly. If they don’t function well, your eggs may not mature or fertilise correctly. This can lower your chances of conceiving. - Can poor mitochondrial function lead to miscarriage?
Yes, when mitochondria don’t produce enough energy, it can lead to errors in chromosome separation. This may cause genetic problems in the embryo and increase the risk of miscarriage.