Because of this, female age becomes one of the most important determinants of egg quality because as age advances, the further it is from the time the eggs were produced and therefore, the eggs themselves are prone to aging and exposure to internal and external stressors that may affect their quality. Technically, egg quality can be measured by chromosomal abnormalities, DNA damage or mitochondrial DNA damage.
Are there ways to preserve or promote egg quality?
1. Nutrition can play a role in preserving egg quality. For example, Co-enzyme Q10 has been hypothesized to play a role in minimizing the senescence or aging of egg cell mitochondria. Further, CoQ10 has been found in follicular fluid surrounding the egg cell in the ovary. In theory a young body, through the liver, is able to produce enough CoQ10 to keep the body and its cells healthy. However, the production of CoQ10 may decline over time. Further, certain drugs, such as commonly prescribed statin drugs for high cholesterol greatly diminish the body's ability to produce CoQ10.
Another example of nutrients that may improve egg quality includes omega-3 fatty acids, which are found in fish oil, krill oil and algae based DHA-omega 3 fatty acids. Scientists have hypothesizedthat omega-3 fatty acids has the potential of prolonging maternal reproductive life-span as well as egg quality. A rich source of omega-3 fatty acids in our diets is fish--such as salmon, sardines and anchovies--and the recommendation (based on heart health studies) is to eat fish at least twice a week. However, some fishes--notably tuna and swordfish--should be avoided, specially by women of reproductive age because of concerns with heavy metals. In fact, the Environmental Protection Agency, has issued a warning for pregnant women to avoid above mentioned fish when pregnant.
2. Anti-oxidants can reduce oxidative damage to egg cells, and have the potential to actually improve egg quality and fertility rates. Melatonin, a protein produced by the brain at night to promote sleep, is a very potent and effective antioxidant. This incidentally is one of the many reasons why sleep is so good for you. However, several studies have shown that melatonin taken as a supplement can actually also improve egg cell quality and fertility rates. The first study concluded, "In conclusion, oxidative stress causes toxic effects on oocyte maturation and melatonin protects oocytes from oxidative stress. Melatonin is likely to improve oocyte quality and fertilization rates." A second study showed that there was a trend towards improving both egg quality in fertility in that it found that women who took melatonin while undergoing in-vitro fertilization (IVF), both had higher fertilization rate as well as higher numbers of "class 1," i.e. higher quality embryos.
Some studies also used vitamin E as a potential anti-oxidant that may improve antioxidant capacity and reduce oxidative stress in the body.
At our practice, we think about this issue of improving egg quality holistically. We take into consideration not only female age, but also put a lot of inquiry and thought into dietary choices, lifestyle, stress factors--as all of these can increase (or decrease) oxidative stress. We do a very detailed diet recall with our patients and then come up with concrete recommendations on the strengths and weaknesses of their diets and lifestyle. For example, for the most part, we promote a whole foods based diet includes lots of green leafy vegetables (for folic acid, among other things) as well as healthy sources of omega-3 fatty acids. We also try to reduce foods that can increase oxidative stress such as hydrogenated fats, processed foods, excess sugar, excess carbohydrates. For many patients, because they have an urgency to improve their nutrition status to get pregnant soon, we may prescribe some supplements to speed up the process. For example, we are very picky about fish oil, using only reputable brands that are molecularly distilled (to remove heavy metals) and have the correct EPA/DHA content.
Another example is the judicious use of anti-oxidants. We do not think everybody should be on an antioxidant supplement. The first thing we try to reduce is oxidative stress exposure by eating better, getting more sleep, reducing the "burden of chemicals" in our households, office and work spaces.