How to Improve Egg Quality: A Science-Backed Guide

By Zsofia Jamieson, co-founder of The Fertility Class and certified Aviva Method instructor, who conceived with the method after years of PMOS (formerly known as PCOS). 

Last updated October 2026.

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In short: Egg quality is the genetic, mitochondrial and structural health of your eggs. Age matters, but each egg matures over roughly 90 days, and ovarian blood flow, nutrition, sleep and stress all shape the egg you will ovulate three months from now.

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Egg quality sits at the center of The Fertility Class approach because it is foundational to reproductive health, and because two of its strongest influences, ovarian blood flow and nervous system regulation, are exactly where targeted movement can make a measurable difference.

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Key takeaways

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• Egg quality describes the genetic, mitochondrial and structural health of an oocyte, the cell that becomes your egg.
• Age influences egg quality, but it does not decide it alone. Eggs spend roughly 90 days maturing before ovulation, and the choices you make during that window matter.
• The strongest levers in the research are ovarian blood flow, nutrient density, oxidative stress and metabolic health.
• The most consistent interventions are targeted movement, a Mediterranean-style way of eating, quality sleep and stress regulation.
• For women over 35, beginning these practices three to six months before trying to conceive, or before an IVF cycle, reflects the way follicles actually develop.

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When women begin researching their fertility, egg quality is often the first phrase they meet and the hardest one to find a clear answer about. It sits at the center of a great deal of worry, especially after 35, and a great deal of marketing.

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In simple terms, egg quality describes the chromosomal, mitochondrial and structural health of an oocyte, the immature cell that develops in the ovary and is released at ovulation. A higher-quality egg has the cellular machinery to be fertilized, divide normally, develop into a viable embryo and implant.

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It also helps to know what egg quality is not. It is not the same as egg quantity, or ovarian reserve, which is usually measured through AMH and antral follicle count. A woman can have a strong reserve and lower-quality eggs, or fewer eggs of excellent quality. They are different markers of different things, and both matter.

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In reproductive medicine, egg quality is usually assessed indirectly, through fertilization rates, embryo grading in IVF and pregnancy outcomes.

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Egg quality is one of the most important factors in whether a cycle leads to a healthy pregnancy. Lower egg quality has been associated with reduced fertilization rates, higher rates of early miscarriage, lower IVF success per cycle and a greater likelihood of chromosomal differences in embryos. That holds whether a woman is trying to conceive naturally, with IUI or with IVF.

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Almost every woman trying to conceive eventually asks this, often quietly, and often after reading something discouraging online. The honest answer is yes, within a window, and with realistic expectations.

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The biology behind that answer is what reproductive endocrinologists call the 90-day rule. Eggs do not mature overnight. Each egg released at ovulation has spent roughly the previous 90 days in follicular development, and throughout that window the developing follicle responds to its environment: blood supply, oxidative stress, metabolic signals, sleep, nutrition and stress hormones.

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In practice, the egg you ovulate this month began developing three months ago, and the choices you make today are shaping the egg you will release roughly 90 days from now. That window is your leverage point. It is also why fertility specialists often recommend a three-month preparation period before an IVF cycle.

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This is where the heart of The Fertility Class sits. Healthy ovarian blood flow delivers oxygen, nutrients and hormonal signals to developing follicles, and Doppler ultrasound research has repeatedly associated reduced ovarian blood flow with poorer follicle maturation, lower oocyte quality and lower success rates in assisted reproduction. For the full set of studies we draw on, visit our Studies page.

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Targeted, rhythmic movement that engages the deep lower abdominal and pelvic muscles around the ovarian blood supply is designed to support that circulation. It is the principle the Aviva Method has worked with for decades, and it aligns closely with what reproductive medicine increasingly tells us about vascular health and oocyte development.

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A word on intensity, because it is so often misunderstood. More is not better. Very high-intensity exercise, especially combined with low energy availability or restrictive eating, can disrupt the hypothalamic signals that trigger ovulation in the first place. In our years of working with women, we have found that 30 minutes of fertility-focused movement two to three times a week, paired with a daily walk, is enough to make a real difference.

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If you are curious how fertility exercise differs from a typical fertility yoga class, we explain it here: why The Fertility Class is different from fertility yoga.

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The strongest body of evidence points to a Mediterranean-style way of eating. Most of our members already eat well, so for them this is less a correction than a refinement. In broad strokes, the pattern looks like this:

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• Olive oil as the primary fat
• Plenty of vegetables, legumes and whole grains
• Fish and quality protein, including red meat in moderation, which can matter for iron and B12 status while trying to conceive
• Nuts, seeds and antioxidant-rich foods
• Less reliance on refined carbohydrates, processed foods and added sugar

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This way of eating supports egg quality through several mechanisms: steadier blood sugar, which lowers oxidative stress; adequate micronutrients such as folate, B12, iron, zinc and omega-3s; and a lower inflammatory load.

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A few nutrients have particularly meaningful associations with oocyte health:

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• Omega-3 fatty acids, associated with improved embryo morphology
• Folate, important for chromosomal integrity
• Vitamin D, with status correlated with IVF outcomes in multiple studies
• CoQ10, with some evidence of supporting mitochondrial function in older oocytes, particularly in women over 35 undergoing IVF
• Iron and B12, foundational for ovulation and healthy red blood cells

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Food first, always. Supplements are most useful when chosen carefully, ideally guided by recent bloodwork rather than by whatever is trending online.

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Beyond movement and nutrition, four lifestyle factors have meaningful research behind them.

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Sleep. Quality sleep is one of the most underrated fertility tools there is. It regulates the hormones that govern ovulation, and regularly sleeping fewer than six hours a night, or sleeping poorly, has been associated with weaker reproductive outcomes.

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Stress. Chronically elevated cortisol affects the hormonal axes that control the cycle and may impair mitochondrial function in the egg. Breathwork, mind-body practice, time outdoors and genuine rest are not soft advice. We give them equal weight to everything else on this list, and the calming effect of the Aviva Method is one of the reasons we value it so highly.

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Environmental toxins. A growing body of research associates endocrine disruptors such as BPA, phthalates, certain pesticides and microplastics with reduced oocyte quality and weaker IVF outcomes. We cover this in depth in Microplastics and Fertility. The practical summary: filter your water, store food in glass, avoid heating plastics and choose lower-toxicity personal care products where you can.

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Smoking and alcohol. Smoking is one of the most clearly demonstrated harms to egg quality and accelerates ovarian aging. Heavy drinking is also associated with reduced fertility. The evidence on moderate alcohol is less settled, though most fertility specialists suggest limiting it while trying to conceive. Our view is simple: it does nothing to help, so there is little reason to ask your body to process it.

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This is the question that brings most women to the topic in the first place, and it deserves an honest answer.

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Egg quality does decline with age. The decline tends to accelerate after about 35, and again after 40. By the late 30s and early 40s, a higher proportion of eggs carry chromosomal differences, which is part of why miscarriage rates rise with age, whether a woman conceives naturally or through IVF.

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That is biology, and we believe in being clear about it. We also believe in being clear about what else is true:

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• Many women in their late 30s and 40s conceive and carry healthy pregnancies.
• The 90-day window of follicular development applies at every age, so the choices you make today still influence the egg you ovulate three months from now.
• Some interventions, notably CoQ10, have shown stronger effects specifically in women over 35.
• Reproductive endocrinologists often suggest that women over 35 begin preparing three to six months before trying to conceive, and consider baseline AMH and antral follicle count testing for a clearer picture of reserve.

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Age sets a baseline. Your daily choices still count.

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Sperm health matters just as much, and it often responds to lifestyle changes even faster. Sperm regenerate roughly every 72 days, a shorter window than the egg’s 90.

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The principles are similar: moderate movement, Mediterranean-style nutrition, good sleep, stress regulation, avoiding heat exposure such as saunas, hot tubs and laptops on the lap, and limiting alcohol and smoking. Our dedicated men’s program covers all of this in detail.

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Roughly 90 days, the length of follicular development before ovulation. Most evidence-aligned approaches suggest three to six months of consistent practice before trying to conceive or starting an IVF cycle.

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Not directly. Egg quality is usually inferred from IVF outcomes, such as fertilization rates, embryo grading and genetic testing of embryos, or more indirectly from pregnancy outcomes. AMH and antral follicle count measure egg quantity, not quality.

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Research suggests targeted, moderate exercise supports ovarian blood flow and metabolic health, both of which are associated with oocyte quality. Excessive high-intensity training can have the opposite effect. The principle is targeted, sustainable movement with genuine rest days.

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There is moderate evidence, particularly in women over 35 undergoing IVF, that CoQ10 may support mitochondrial function in eggs. It is one of the better-supported supplements in this space, though not a guarantee. Speak with your physician first, especially if you take other medications or supplements.

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Yes. In PCOS, a condition experts have proposed renaming PMOS to reflect its metabolic roots, insulin resistance and elevated androgens often drive irregular ovulation and can affect egg quality. Targeted exercise, a lower-glycemic way of eating and stress regulation all improve insulin sensitivity, which supports both ovulation and egg quality. Many of our members come to us with PCOS, and it is a path our co-founder Zsofia walked herself. Read more in PCOS, Exercise and Fertility.

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No. The 90-day window applies throughout the reproductive years. Baseline egg quality is lower after 40, but the same levers, blood flow, nutrition, sleep and stress, still work, and many women conceive after 40.

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So much in fertility can feel out of your hands. Egg quality is not entirely one of those things. If you have menstrual cycles, your body is in a 90-day window right now, and how you care for yourself during it is some of the most meaningful work you can do for the egg you will ovulate three months from now.

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If you are just starting out, you have time. If you are further along, every week counts. And if you are working with a fertility clinic, these foundations matter just as much alongside your treatment.

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• Ovarian blood flow and egg quality
• Ovarian blood flow and ovarian function
• Ovarian blood flow and follicle development in assisted reproduction
• Moderate physical activity and reproductive outcomes
• Vigorous exercise and subfertility
• Stress and reproductive hormone signalling

More research on our Studies page