Egg Quality Isn't Just About Age: What's Being Missed Before IVF

You read It Starts With the Egg. You removed gluten and dairy, started CoQ10, cleaned up your diet, and went into your cycle believing you had done everything you could.

Then the embryos stopped developing again. Or the transfer failed again. And the explanation you were given was the same one you have heard before: poor egg quality.

If that is where you are right now, you already know that changing the protocol does not seem to change the outcome. Different stimulation, different clinic, different supplements, and the same result. That pattern is not bad luck. It is a signal that something in the biological environment those eggs developed in has not been evaluated.

Age is still one of the most important factors in egg quality, but it is not the only one.

Poor egg quality is not a diagnosis. It is a description of what the clinic observed at retrieval. It tells you the eggs did not perform as expected. It does not explain why, nor does it tell you what shaped those eggs during the 90 days before they were retrieved.

That is the gap. And it is almost always where the answer is.

 "I have already done everything. I don't know what else there is."

What Poor Egg Quality Actually Means

You have searched this. You have read the forums, the studies, the blogs. And every answer circles back to the same thing: egg quality. Improve your egg quality. Support your mitochondria. Take CoQ10.

You have done that. And you are still here.

So let's be direct about something. Poor egg quality is not an explanation. It is what the clinic observed at the end of a process they never looked at. Embryos that arrested. A transfer that failed. Genetic results that came back abnormal. Those are outcomes. They describe what happened. They do not tell you why.

The why lives in the 90 days before retrieval. The environment your follicles were developing inside. The energy available to those eggs as they matured. What was happening in your body during those three months that nobody connected to what showed up at retrieval.

That is the conversation that is not happening. The protocol gets changed. The stimulation gets adjusted. But the biological environment those eggs developed in stays the same. So the result stays the same. And you get the same explanation again.

Something is being missed. You already know that. The question is what.

Why age isn't the whole story with egg quality

What you can do when you have been told poor egg quality

What Is Actually Happening

Here is what the clinic is not telling you.

Your egg did not fail at retrieval. It arrived at retrieval already reflecting everything that happened to it in the three months before. The environment it developed inside. The energy it had available. What your body was dealing with during that window.

By the time that egg was retrieved, the outcome was already shaped.

The embryo runs on the energy the egg brought to fertilization. Until Day 3 it has not activated its own genome yet. It is running entirely on what the egg provided. If that energy was compromised during the development window, the embryo runs out of fuel. It stalls. Often at exactly the same point every cycle. Not because your eggs are broken. Because the environment that shaped them has not changed.

Chromosomal problems follow similar logic. Age matters. But oxidative stress, inflammation, and blood sugar instability have been associated with chromosomal accuracy independently of age. This is why younger women get abnormal embryos. And why the same woman can produce normal embryos one cycle and abnormal ones the next, with no obvious explanation. Something in the environment shifted. The age did not.

The pattern is the clue. And the pattern is almost never what gets investigated.

Liu et al. Mitochondrial dysfunction in oocytes: implications for fertility and ageing. Journal of Ovarian Research. 2025.

Van Blerkom J. Mitochondrial function in the human oocyte and embryo. Fertility and Sterility. 2011.

How gluten affects egg and sperm health

How declining sperm counts and egg quality are connected

Gluten, embryo implantation, NK cells, AMH and FSH 

You Already Know About the 90 Day Window

You know about the 90 day window. You have been optimizing for it. CoQ10, methylfolate, cutting out gluten, and cleaning up your diet. You did the work.

So why didn't it work?

Because the 90 day window is only useful if you know what is actually disrupting it, and most women are optimizing in the dark. They are adding supplements without knowing if their gut is absorbing them. They are taking folic acid with an MTHFR variant, which means their body cannot convert it. They are managing stress but running on cortisol that is quietly suppressing the very hormonal signals they are trying to support.

Doing the right things inside the wrong environment does not move the needle. And nobody is looking at the environment.

Are your supplements actually being absorbed? 

What Nobody Has Looked At

This is where the real conversation starts. Each of these systems directly shapes the environment your eggs are developing in. When they are dysregulated, egg quality suffers. When they are addressed, outcomes change.

Blood Sugar

If your energy crashes in the afternoon, if you wake up at 3am, if you feel better after you eat and worse when you skip meals, your blood sugar may be affecting your egg quality. Your body prioritizes survival over reproduction. When blood sugar drops, cortisol rises to compensate. Prolonged elevated cortisol interferes with the hormonal balance that egg development depends on.

Unstable blood sugar can drive inflammation and oxidative stress, both of which have been linked to impaired mitochondrial function inside the follicle. This is not a distant connection. It is a direct one. And it is seldom part of the conversation about why embryos are arresting.

Why balancing blood sugar is essential for embryo implantation 

Blood sugar and egg quality: the fertility link you cannot ignore  

Inflammation

Chronic low grade inflammation has been associated with impaired mitochondrial function in the egg, accelerated ovarian aging, and chromosomal instability, which may be labeled poor egg quality. It is one of the most consistent findings in our case reviews and one of the least investigated markers in a standard fertility workup.

hsCRP is the marker. Below 1 mg/L is the functional target for fertility. Standard labs flag anything under 3 as normal. That gap matters. Research shows that hsCRP between 1 and 3 mg/L is associated with a 67% increased risk of pregnancy loss. Women often have numbers sitting in what their clinic considers perfectly acceptable, that may be working against egg quality and implantation.

Homocysteine is the other marker worth checking. Elevated homocysteine signals a methylation problem and is directly linked to miscarriage risk and implantation failure. It is almost never checked as part of a fertility workup.

A Mediterranean diet is often recommended. It is a reasonable starting point, but it is only the beginning, and for many women it is not enough. The foods that drive inflammation are not the same for everyone. Gluten, dairy, corn, soy, eggs, peanuts, processed sugar, and seed oils. These are the top allergens and inflammatory triggers we see consistently. A Mediterranean diet does not remove them. If you have an unidentified food sensitivity and you are eating a Mediterranean diet, you may be eating the food that is driving your inflammation every single day and have no idea.

The elimination diet is where we start with every client. You remove the top triggers for 10 days and reintroduce them systematically to identify exactly what your body is reacting to. We see women who have been eating clean for years, organic, whole foods, mostly Mediterranean, hsCRP still elevated, embryos still arresting. One food sensitivity is identified and removed and the entire picture starts to shift.

IFM. The Inflammatory Response and Reproductive Health. 

Why inflammation may be driving poor egg quality and miscarriage 

The gut-fertility connection for poor egg quality and low AMH 

What gut health has to do with hormone balance and fertility 

How the oral microbiome affects egg and sperm quality 

Gut Health

The gut is upstream of almost everything that affects egg quality. It determines whether the nutrients you are taking actually reach the follicle. It regulates how estrogen is metabolized and cleared. And when it is compromised, it can contribute to the kind of chronic low grade inflammation that has been associated with impaired mitochondrial function in the egg.

Many of our clients with low AMH and poor embryo outcomes have gut dysbiosis with zero digestive symptoms. No bloating, no discomfort, nothing obvious. The clue is usually that their nutrients do not respond to supplementation. Ferritin stays low. Vitamin D does not hold. CoQ10 taken for months with no change in embryo outcomes. That is the gut telling you something. Until gut function is addressed, other interventions work against the current.

Are your supplements actually being absorbed? 

Thyroid

We see this constantly. TSH is normal. The full thyroid picture is not. Thyroid hormones regulate the communication between the hypothalamic pituitary ovarian axis and the developing follicle. Subclinical dysfunction, patterns sitting within normal ranges, affects follicular development and egg quality without triggering a diagnosis.

Thyroid peroxidase antibodies have been detected directly in follicular fluid. That immune activation creates a cytotoxic environment the egg is developing inside, even when TSH looks completely normal. A 2025 meta analysis confirmed lower implantation and fertilization rates in IVF for women with thyroid antibody positivity regardless of TSH level. The antibodies affect egg quality. TSH alone will not tell you they are there.

Hashimoto's Thyroiditis and Female Fertility. PMC. 2025. 

Can hypothyroidism cause infertility?

Methylation and the B Vitamins Most People Are Getting Wrong

Your body needs to activate the nutrients you are taking. Methylation is the process that makes that possible. It drives DNA repair in the egg, gene expression, hormone production, and detoxification. When it is sluggish, none of those processes run efficiently. Poor egg quality, chromosomal errors, and early pregnancy loss have all been linked to compromised methylation. And it is rarely evaluated as part of a standard fertility workup.

The most common reason we see methylation undersupported is folic acid. Do not take folic acid. Take methylfolate. Folic acid is synthetic and requires conversion steps that many women cannot complete efficiently. When that conversion is slow, unmetabolized folic acid builds up in the blood and the methylation pathway stays underfueled regardless of how consistently you are supplementing.

But folate is not the only piece. Methylation runs on a full B vitamin complex. B12 in the methylcobalamin form. B6. Riboflavin. These are the cofactors that keep the entire pathway running. When they are low, and they are frequently low in women who have been under chronic stress, restricting food, or dealing with gut absorption issues, the whole system slows down and egg quality may be affected.

Genetic testing to understand your specific methylation variants gives us the full picture of where the pathway needs support and exactly which forms of which nutrients will work for your body. We look at this in almost every case we review.

Hart RJ et al. Nutritional supplements and IVF: an evidence based approach. Reproductive BioMedicine Online. 2023.

Shang Y et al. Antioxidants and Fertility in Women with Ovarian Aging. Advances in Nutrition. 2024.

Why methylfolate matters more than folic acid for egg quality

MTHFR, methylation, and fertility

Ferritin

Ferritin is the finding we catch most consistently and the one most often sitting in plain sight in previous labs. Lab ranges flag normal at 12 to 15 ng/mL. The functional threshold for fertility is 80 to 100 ng/mL. Low ferritin in the normal lab range impairs oxygen delivery to the follicle and shows up constantly in Day 3 arrest patterns. The mitochondria in your eggs need adequate oxygen to produce the energy that drives development. When ferritin is low, that oxygen delivery is compromised and embryo development stalls at the same stage cycle after cycle.

It is almost never checked as part of a fertility workup. And when it is, the lab range creates a false sense of security.

Ferritin, iron deficiency, and what it means for fertility

Male Factor

Embryo development reflects both partners. This gets lost when every conversation after a failed cycle centers on egg quality.

Standard semen analysis measures count, motility, and morphology. It does not assess DNA integrity. A normal result does not rule out fragmentation. When fertilization is normal but development stalls between Day 3 and Day 5, sperm DNA integrity is a direct contributor to that pattern. Not egg quality alone. Both. A 2025 study of 870 ICSI cycles found that each 1% increase in sperm DNA fragmentation reduced top quality Day 5 blastocyst rates by 2.5%. Your partner needs to be part of this conversation every single cycle.

Sperm DNA Fragmentation Impairs Early Embryo Development: 870 ICSI Cycles. MDPI Int J Mol Sci. 2025.

Boosting male fertility before IVF 

Why IVF keeps failing when the protocol changes 

The Nervous System

This one does not look like stress. That is why it gets missed.

She is not falling apart. She is highly functional, probably the most organized person in the room. She has a spreadsheet for her supplements, she has read every study, she knows her labs better than most clinicians. Her superpower is that she keeps going. And that superpower, sustained over months or years of this, has a physiological cost that nobody has measured.

It is not about how stressed you feel. It is about what your body is doing underneath. Elevated cortisol impairs mitochondrial efficiency in the egg. It disrupts thyroid hormone conversion. It reduces progesterone. It drives the blood sugar instability that feeds back into the whole pattern. All of it is happening in the background of a 90 day window you are trying to optimize.

Reverse T3 is the marker worth checking. When the body is under sustained load it converts available thyroid hormone into an inactive form. TSH looks normal. Free T3 looks okay. But the active hormone is not getting to the cells that need it, including the follicle. A flattened cortisol curve is another. Not high cortisol, but flat cortisol. Low in the morning when it should be high, unstable through the day. That pattern disrupts the entire hormonal cascade that supports egg development. And fasting insulin above 5 means the metabolic environment those eggs are developing in is compromised regardless of how clean the diet is.

This is why working on the nervous system is not optional in our approach. It is upstream of egg quality. And it is almost never the conversation that happens at the clinic.

How perfectionism is affecting your fertility and egg health 

9 signs your job may be affecting your fertility 

Adrenal support when trying to conceive 

A Pattern We Recognized

Catherine was 41 with endometriosis and had been through multiple egg retrievals. Every time the result was the same. Terrible egg quality. She had changed protocols, worked with different specialists, and kept going the way determined people do.

When she came to Fab Fertile we looked at the full picture. What we found was a pattern of things that had been present for years and had never once been connected to her fertility.

• Blood sugar instability. Shaky between meals, energy crashes, hypoglycemic episodes.
• Thyroid dysregulation. Cold all the time, dry skin, ridged nails.
• Gut dysfunction since childhood. Bloating, constipation. Functional testing found H. pylori and deep gut infections that had never been identified.
• Nervous system dysregulation. Not the kind that looks like stress from the outside. Sensitivity to loud noises, brain fog, difficulty thinking clearly.
• Anemia, immune imbalances, fibroids and ovarian cysts that had required surgery.

None of it had ever been connected to her egg quality. None of it had been investigated as part of her fertility workup.

When the full picture was addressed everything shifted. Her next retrieval produced great quality eggs. She had a successful transfer. Catherine and her husband are now the incredibly proud and happy parents of a baby boy. 

Read Catherine's full story 

We share Catherine's story because somewhere in it you probably recognized something. Maybe it was the blood sugar crashes. Maybe it was the thyroid symptoms that never got taken seriously. Maybe it was the gut issues you have had so long you stopped mentioning them. Maybe it was just the feeling of doing everything right and still getting the same answer.

That is exactly the point. Every one of those things was affecting her egg quality. None of them showed up in the conversation about egg quality.

What We See in Case Reviews

Catherine's case is not unusual. The details are hers but the pattern shows up constantly.

• Embryos fertilize normally and arrest at the same stage every cycle. Different protocol. Same result. The biological environment was never evaluated between cycles.
• Ferritin is sitting at 18 to 22 ng/mL, and the lab flagged it as normal. The functional threshold for fertility is 80 to 100 ng/mL. That gap directly affects oxygen delivery to the follicle and mitochondrial function in the egg.
• hsCRP is between 1 and 3 mg/L. The clinic considers it unremarkable. At that level the research shows an associated increased risk of pregnancy loss. The inflammation is real and may be affecting egg quality
• Folic acid is being taken instead of methylfolate. Genetic testing reveals an MTHFR variant. The methylation pathway supporting DNA repair and chromosomal accuracy in the egg is undersupported.
• Sperm DNA fragmentation has never been tested. Semen analysis was normal, so male factor was ruled out. These are not the same thing.
• Thyroid antibodies are present in previous labs. Nobody connected them to the egg quality picture.
• CoQ10 has been taken for six months or more with gut dysbiosis present. The supplement is not reaching target tissues. The gut has to work before the supplements can.
• Nervous system is in chronic output mode. Reverse T3 is elevated. The body is prioritizing survival and quietly diverting resources away from the follicle. 

The information was often already there. In previous labs, in the symptom history, in the pattern across cycles. It just was not being read as a connected picture.

Where Time Gets Lost

Most women who come to us are not starting from zero. They have already spent months or years doing the right things. The issue is not effort. It is that the right questions have not been asked.

Focusing only on AMH. AMH tells you how many follicles are likely to be recruited. It tells you nothing about the environment those follicles are developing inside, what is suppressing the signal, or why the eggs that are retrieved are not performing. When AMH becomes the primary number in the conversation everything sitting underneath it gets ignored.

Why low AMH is not the whole picture 

A functional approach to low AMH 

Repeating the same protocol. A new stimulation approach changes the timing and the hormone levels. It does not change mitochondrial function, gut absorption, thyroid conversion, blood sugar stability, inflammation, or sperm DNA integrity. The protocol changes. The environment does not.

Skipping functional testing. Standard fertility labs are designed to diagnose disease. They are not designed to identify the patterns that sit below the threshold of diagnosis but above the threshold of optimal function. Ferritin at 22 ng/mL is not a disease. It is also not sufficient for egg quality. hsCRP at 1.5 mg/L is not flagged. It is also not neutral. Sperm DNA fragmentation is not on a standard semen analysis. Thyroid antibodies are not on a standard thyroid panel. MTHFR is not checked unless someone specifically asks. That gap between normal and optimal is where most of the answers live.

Before You Do Another Cycle

If you are preparing for another retrieval and poor egg quality is still the only explanation you have been given, this is the moment to pause.

Not to add another supplement. Not to find a new protocol. To ask whether the biological environment that produced the last result has actually been looked at.

The questions worth asking before the next cycle:

• Has your full thyroid panel been run including antibodies, Free T3, and Reverse T3. Not just TSH.
• Has your hsCRP and homocysteine been checked. Not just ruled out because they are under 3.
• Has your ferritin been checked against a fertility threshold, not just a lab reference range.
• Has your MTHFR status been tested and are you taking methylfolate or folic acid.
• Has your gut been evaluated with functional stool testing, not just symptom review.
• Has your partner had a sperm DNA fragmentation test. Not just a semen analysis.
• Has anyone looked at your cortisol pattern and Reverse T3 as markers of nervous system load.

These are not exotic tests. They are the questions that change the picture when the standard workup has not been enough.

The 90 day window before your next retrieval is the most important window available to you. What changes in that window is what changes the outcome. But you cannot change what has not been identified.

Embryo Arrest at Day 3 or Day 5 | Inflammation and Immune Signaling | Male Factor Fertility | Low AMH in Context]

Questions We Hear Most

Why do my embryos keep stopping if fertilization was fine?

Fertilization just means the egg and sperm combined. What happens after that depends on the energy the egg brought to the table and whether the sperm DNA was intact enough to sustain development past Day 3. When fertilization works but embryos consistently stall, both partners are part of that picture. It is almost never just one thing and it is almost never just egg quality.

My AMH is normal. Can egg quality still be an issue?

Yes. AMH counts follicles. It says nothing about what is happening inside them or the environment they are developing in. Normal AMH with poor embryo outcomes means the quantity was there. Something in the environment those eggs developed in was not.

I have been taking CoQ10 for months. Why is nothing changing?

Because CoQ10 only works if it is actually being absorbed. If your gut is compromised it is not reaching the follicle. Form matters too. Ubiquinol is the active form and absorbs significantly better, especially for women over 35. But even the right form in the right dose cannot overcome an environment that has not been addressed. Inflammation, blood sugar instability, thyroid dysfunction, compromised methylation. CoQ10 does not fix those. It works within them.

Semen analysis was normal. Does my partner still need testing?

Yes. A semen analysis does not test DNA integrity. Those are completely different things. When embryos fertilize and then stall after Day 3, sperm DNA fragmentation is one of the first things we look at. It is also one of the last things that gets tested in a standard workup.

Is it just my age?

Age is real. It is not the whole story. We see women in their early 40s produce great quality eggs after addressing the right things. We also see younger women with poor embryo outcomes that have nothing to do with age. What changes outcomes is identifying what is actually driving the pattern. Age is one input. The biological environment is another. And unlike age, the environment can change.

Sources and Research

1. Liu et al. Mitochondrial dysfunction in oocytes: implications for fertility and ageing. Journal of Ovarian Research. 2025. 

2. Hart RJ et al. Nutritional supplements and IVF: an evidence-based approach. Reproductive BioMedicine Online. 2023. 

3. Shang Y et al. Antioxidants and Fertility in Women with Ovarian Aging. Advances in Nutrition. 2024.

4. Van Blerkom J. Mitochondrial function in the human oocyte and embryo. Fertility and Sterility. 2011.

5. Sperm DNA Fragmentation Impairs Early Embryo Development: 870 ICSI Cycles. MDPI Int J Mol Sci. 2025. 

6. Hashimoto's Thyroiditis and Female Fertility. PMC. 2025. 

7. IFM. The Inflammatory Response and Reproductive Health. 

8. ASRM. Subclinical hypothyroidism in the infertile female population: a guideline. 2024.

9. Bentov Y et al. The role of mitochondrial function in oocyte competence. Fertility and Sterility. 2011.