It starts with the egg
Egg quality (or oocyte quality) is a big factor in fertility. Egg quality naturally declines with age, but there are other factors that affect egg quality as well. Egg quality affects the ability of the egg to be fertilized but also the ability of the embryo to divide and develop into a fetus. So it’s important to improve egg quality! And improve it you can! There are many things you can do to improve egg quality, no matter your age or diagnoses. In my practice, I assume most women of any age struggling with fertility should probably work on egg quality, and depending on the patient, a big part of pre-conception plans as well!
First, let’s start with what factors affect egg quality. The biggest one is age! Women are born with all the eggs they will ever have. Number and quality start declining when they are a still a fetus. So when a woman is in her late 30’s she has a lot less eggs than she did when she was 18. This is called reduced ovarian reserve. When eggs are older, they have decreased mitochondrial health (the power house of the cell, or the part of the cell responsible for making energy molecules), including decreased number of mitochondria in egg cells, and an increased risk of an abnormal number of chromosomes in a cell, which is mainly due to a decreased ability for those cells to divide well. Mitochondria are extremely important at many steps of conception, including fertilization, pre-implantation development of the embryo, and different stages of cell division. As we age, mitochondria are adversely affected, resulting in mitochondria looking different, damaged mitochondrial DNA, and they don’t produce energy molecules as well as they once did. Telomeres, chromosome bonds, and mitotic spindles are all parts of the egg that are adversely affected by aging and all affect the ability of the cell to divide well. But there is good news! The underlying cause of age affecting these aspects of the egg is oxidative damage from reactive oxygen species, also called oxidative stress. So adding in powerful antioxidants in the diet, reducing sources of oxidative stress in the environment and lifestyle, and supplementing with the right antioxidants for that woman can combat the adverse effects aging has on eggs.
Improving egg quality
Another aspect of egg health is methylation disorders. Methylation disorders are a set of epigenetic disorders of attaching methyl groups to molecular compounds that result in abnormal enzyme production and function that are implicated in a huge range of human diseases. Methylation disorders affect egg and sperm cells and how well they divide, and has been shown to be associated with fertility outcomes. Folic acid is a necessity for anyone trying to get pregnant to prevent neural tube defects, but having adequate levels is also associated with higher levels of fertility. However, if a woman has a methylation disorder and she is taking folic acid instead of folate (a different form of the same nutrient), then she can’t convert the folic acid into the usable form of folate. Methylation disorders have also been shown to be associated with the development of autoimmune diseases like hypothyroidism and premature ovarian failure, which are associated with increased risk of miscarriage and lower pregnancy rates. Methylation disorders can also be affected by antioxidant support, which helps reduce activation of the faulty methylation genes. Identifying women who have issues with methylation and dosing the right form of vitamins and antioxidants is important for not only increasing egg quality, but also development of a healthy placenta, reduction in autoimmune disease, and reduction in neural tube defects.
Nutrient status is the last big factor in egg quality. This relates heavily to antioxidant status and mitochondrial function. If your diet doesn’t have enough nutrients in it, or your gut is unhealthy and doesn’t allow for absorption of nutrients, your cells and eggs are going to be nutrient poor. Poor nutrient status can decrease egg quality and fertility rates in a young woman without a methylation disorder, so diet and lifestyle should ALWAYS be the first step. Nutrient status also affects autoimmune disease, healthy metabolism of hormones like estrogen, and systemic inflammation. All of which can affect fertility outcomes. So many nutrients have been found to be important for egg quality. To name a few of the most important: zinc, methyl donors (B12, folate, SAMe), L-carnitine and other amino acids, vitamin C, vitamin E, vitamin D, and the powerhouse CoQ10.
Related to this, women with diabetes, PCOS, or who are obese have altered glucose metabolism in their egg cells that affect energy production and oxidative damage. There are some treatments that specifically treat egg quality issues relating to PCOS and those with metabolic disturbance and are especially important in this population. These are myo-inositol and ALA. A big part of how PCOS affects fertility is through metabolic changes, specifically altered glucose regulation and insulin signalling. These compounds have been found to address lowered egg quality in women with PCOS via these metabolic mechanisms as well as oxidative stress. Again, diet and lifestyle should always be first, so an essential part of treating this type of decreased egg quality is a low carbohydrate, nutrient dense, high antioxidant diet plus regular exercise to regulate blood glucose, insulin levels, and other metabolic hormones.
I’ve mentioned antioxidants a lot so far, but what are they? Antioxidants are compounds that are mainly found in plants like herbs, fruits and vegetables. Making sure that your diet has large amounts of varied fruits and vegetables and your gut is healthy and can absorb them is key! And these food based antioxidants (like vitamin E, vitamin C, zinc, NAC, and carnitine) can be supplemented on top of diet if absorption or deficiencies are suspected or if that compound treats a specific diagnosis. One of my favourite non-food antioxidants is resveratrol, a component found in red wine. While red wine is delicious, there are adverse health outcomes related to drinking wine every day and those kind of cancel out the antioxidants you’ll get from a glass. So a much better way is in pill form! A study on a mouse model of IVF found that eggs from mice who had been treated with resveratrol had improved fertilization, progressing to blastocyst stage embryos, and birth rates after being frozen and then thawed. This study found that resveratrol was beneficial because of it’s antioxidant properties but also by modifying faulty methylation genes and that it was beneficial pre- and post-transfer. However there is recent data that suggests it may change how the uterine lining develops so I only like using this in women who have endometriosis (where it has been shown to benefit uterine lining) or to support egg quality up until the month of trying.
Another non-food antioxidant I love is melatonin, the hormone your body produces that makes you feel sleepy has been found to improve aged eggs and their process of maturation, and it may even have positive effects on female sex hormones that also affect egg quality. Interestingly, our natural production of this hormone declines with age, and while I hesitate to give melatonin in a younger person (to avoid inhibiting their own natural production of the hormone), in an older person melatonin supplementation may be replacing a deficiency! Careful with large doses though, this isn’t necessary for the effect and really really large doses may prevent ovulation from occurring. Amino acids (the building blocks of protein) have been found beneficial in animal studies of egg quality. In cows and pigs, supplementation with L-carnitine (an amino acid, a building block of proteins) was shown to increase glutathione concentration in egg cells and improved energy metabolism. Another amino acid called glutamine was shown to induce egg maturation in cows and pigs. One of my favourite treatments for anything hormonal is n-acetyl-cysteine (or NAC), an amino acid, that has powerful effects on estrogen metabolism, liver detoxification, metabolic dysfunction, glutathione levels, and inflammation. In mice it has been shown to increase telomere length and improve egg quality after 2 months of supplementation, and in humans with PCOS and endometriosis NAC has been shown to improve egg and embryo quality.
When to start
A very key factor when trying to affect egg quality is TIME. The egg a woman ovulates begins maturation approximately 3 months prior to ovulation, so any interventions that are started to improve the quality of an egg has to have begun 3 months prior to support the whole process of maturation off the egg. Which is why any time I’m treating fertility or pre-conception, I like to have at least 3 months of solid work before trying. We can still treat while the couple is actively trying, but the work on egg and sperm quality, and often hormones as well, won’t be realized for at least 3 months.
At the beginning of this 3 month period, an essential part of treatment is assessing gut function and diet. You are what you absorb, and if you’re not absorbing, it doesn’t matter how great your diet is, you will still be relatively nutrient and antioxidant deficient. Step two is identifying methylation disorders and other potential disorders that might affect egg quality like PCOS or endometriosis. Step 3 is supplementing. As a proudly frugal individual myself, I aim to prescribe the fewest amount of supplements possible that cover the most bases, and how much and what supplements are prescribed is always a conversation. What supplements are on the table depends on the age and diagnoses of the patient, whether or not the couple is seeking assisted reproductive technology, and how aggressive the patient wants to be. There are LOTS of supplements and herbs to choose from though, which gives my patients and I a ton of wiggle room.
A question I get a lot is shouldn’t I be able to get everything I need from my diet? Why should I supplement at all? And this is an excellent question! The first factor is the quality of modern food. The reality of our food industry is that modern farming practices create food that isn’t as nutrient dense as it used to be. Buying organic certainly helps, so if you can choose organic that’s optimal for a bunch for reasons. The second factor is what therapeutic doses of nutrients and herbs have been determined by research vs the amounts actually found in food. While I believe there is no pill that can overcome a poor lifestyle, there are some conditions and circumstances that require mega doses of nutrients, and that’s just easier in a pill. For example, studies show 220 mg of zinc sulphate a day helps improve metabolic dysfunction in women with PCOS. The highest content of zinc in a food is 76.3mg per 6 oysters. So to get a therapeutic dose for PCOS from oysters you’d have to be eating 17.3 oysters a day. The next highest amount in food is 6 mg of zinc in 3 ounces of beef. So you could also eat 110 ounces (or approximately 6 pounds) of beef a day. Both of these are such large amounts it would be insane to accomplish in one day, let alone every day. Some nutrients like vitamin C are super easy to get therapeutic amounts from food, while others like zinc are just easier in pills.
To sum up, egg quality is really important in the treatment of fertility in women. It’s affected by a whole host of things, including things that can’t be changed (like age and genes) but a ton of things that can be (oxidative stress, methylation disorder treatment, nutrient status, and metabolic health). It’s all about finding a healthy lifestyle, the right treatments, and giving it enough time!
– Dr. Shannon is a Naturopathic Doctor and RMT in Calgary, Alberta. To learn more about Dr. Shannon or Naturopathic medicine, email her at drshannon@calgarynaturopathiccare.com or book a complimentary 15 minute meet and greet at Country Hills Massage Therapy by calling 403-547-2243 or scheduling online.
This website is not to be used as a diagnostic or treatment tool, and is intended to be used for informational purposes only. Always consult with your Medical Doctor or Naturopathic Doctor for specific concerns. In cases of medical emergencies visit your nearest hospital or call 9-1-1.
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