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Published on: 3/22/2026

The Energy Vitamin and Your Eggs: Signs of Deficiency and Next Steps

Vitamin B12 deficiency can contribute to fertility problems by impairing DNA synthesis, elevating homocysteine, and disrupting ovulation, which can reduce egg quality, hinder implantation, and raise miscarriage risk.

There are several factors to consider; see below for who is at higher risk, key symptoms, the tests that confirm deficiency, recommended intakes, diet and supplement options including injections, related nutrients to check, and guidance on when to see a doctor or fertility specialist for next steps.

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The Energy Vitamin and Your Eggs: Signs of Deficiency and Next Steps

When you're trying to support your fertility, nutrition matters. One nutrient that doesn't always get enough attention is vitamin B12, often called the "energy vitamin." It plays a critical role in nerve health, red blood cell production, and DNA synthesis. But many people don't realize it also plays a role in reproductive health.

So, can a lack of Vitamin B12 cause infertility? The short answer: it can contribute to fertility problems, especially if the deficiency is significant and untreated. Let's break down how B12 affects your body, your eggs, and what to do if you suspect a deficiency.


What Is Vitamin B12 and Why Does It Matter?

Vitamin B12 (cobalamin) is a water-soluble vitamin found primarily in animal products such as:

  • Meat
  • Fish
  • Dairy
  • Eggs

It is essential for:

  • Making healthy red blood cells
  • Supporting the nervous system
  • Building and repairing DNA
  • Helping cells divide properly

Because egg cells and early embryos rely heavily on healthy DNA replication and cell division, B12 plays an indirect but important role in fertility.


Can a Lack of Vitamin B12 Cause Infertility?

Yes, a lack of Vitamin B12 can contribute to infertility, especially when the deficiency is moderate to severe.

Here's how:

1. Impaired DNA Synthesis

Vitamin B12 is essential for DNA production. Without adequate levels:

  • Cells cannot divide properly
  • Egg quality may decline
  • Embo development may be impaired

This may reduce the chances of successful fertilization or implantation.

2. Elevated Homocysteine Levels

Low B12 can increase homocysteine, an amino acid in the blood. High homocysteine levels have been linked to:

  • Ovulation problems
  • Poor egg quality
  • Increased risk of miscarriage
  • Implantation failure

Balanced B12 levels help keep homocysteine under control.

3. Ovulatory Dysfunction

Severe B12 deficiency may interfere with:

  • Regular menstrual cycles
  • Proper ovulation

While it is rarely the sole cause of infertility, it can be one contributing factor—especially when combined with other nutritional deficiencies.

4. Increased Risk During Early Pregnancy

Even if conception occurs, low B12 levels may increase the risk of:

  • Early pregnancy loss
  • Neural tube defects in the developing baby
  • Anemia during pregnancy

For these reasons, adequate B12 is important before and during pregnancy.


Who Is at Higher Risk for B12 Deficiency?

Not everyone is equally at risk. You may be more vulnerable if you:

  • Follow a vegan or strict vegetarian diet
  • Have had weight-loss or gastric surgery
  • Have digestive disorders (Crohn's disease, celiac disease)
  • Take metformin or long-term acid-reducing medications
  • Are over age 50
  • Have pernicious anemia

Because B12 absorption requires stomach acid and intrinsic factor (a protein made in the stomach), digestive issues can significantly reduce absorption—even if your diet contains enough B12.


Signs and Symptoms of Vitamin B12 Deficiency

B12 deficiency can develop slowly. Early symptoms are often subtle and easy to overlook.

Common signs include:

  • Fatigue or weakness
  • Pale or yellowish skin
  • Shortness of breath
  • Dizziness
  • Tingling or numbness in hands and feet
  • Memory issues or brain fog
  • Mood changes, including depression or irritability
  • Glossy or sore tongue

In more advanced cases, neurological damage can occur. That's why early detection matters.

If you're experiencing any of these symptoms and want to understand whether they could be related to a deficiency, Ubie's free AI-powered Vitamin B12 Deficiency symptom checker can help you evaluate your symptoms in just minutes and guide you toward the right next steps.


How Is B12 Deficiency Diagnosed?

A doctor can evaluate B12 status with:

  • Serum vitamin B12 blood test
  • Methylmalonic acid (MMA) test
  • Homocysteine levels
  • Complete blood count (CBC)

Sometimes, "normal" lab values can still mask functional deficiency. If fertility is a concern, it's reasonable to ask for a thorough evaluation.


How Much Vitamin B12 Do You Need?

For most adults, the recommended daily amount is:

  • 2.4 micrograms per day

During pregnancy:

  • 2.6 micrograms per day

However, individuals with deficiency may need much higher doses temporarily under medical supervision.


Next Steps If You Suspect a Deficiency

If you're wondering, "Can a lack of Vitamin B12 cause infertility in my case?" the best next step is evaluation—not guesswork.

1. Speak to a Doctor

If you have:

  • Persistent fatigue
  • Neurological symptoms
  • Difficulty conceiving
  • History of miscarriage
  • Risk factors for deficiency

You should speak to a doctor promptly. Untreated B12 deficiency can cause serious and sometimes irreversible nerve damage. Do not delay medical care if symptoms are severe.

2. Adjust Your Diet

If your diet is low in animal products, consider:

  • Fortified cereals
  • Fortified plant milks
  • Nutritional yeast with added B12
  • B12 supplementation

Food alone may not correct moderate to severe deficiency.

3. Consider Supplementation

Treatment may include:

  • Oral B12 supplements
  • High-dose sublingual tablets
  • B12 injections (for absorption issues)

In many cases, fertility improves once deficiency is corrected—especially if B12 was a contributing factor.

4. Check Other Nutrients

B12 works closely with:

  • Folate
  • Iron
  • Vitamin B6

A full nutritional panel may be helpful if you're addressing fertility concerns.


Can Correcting B12 Improve Fertility?

In individuals with documented deficiency, correcting low B12 levels may:

  • Improve ovulation
  • Lower homocysteine levels
  • Support egg quality
  • Reduce miscarriage risk

However, infertility is often multifactorial. B12 is rarely the only cause, but it can be one piece of the puzzle.

If you've been trying to conceive for:

  • 12 months (if under 35)
  • 6 months (if over 35)

It's wise to consult a fertility specialist in addition to evaluating nutritional factors.


The Bottom Line

So, can a lack of Vitamin B12 cause infertility?

Yes, it can contribute—particularly by impairing DNA synthesis, raising homocysteine levels, and affecting ovulation and early embryo development. Severe or prolonged deficiency may increase miscarriage risk and pregnancy complications.

The good news: B12 deficiency is usually treatable once identified.

If you're experiencing symptoms like fatigue, tingling, or difficulty conceiving, don't ignore them. Use Ubie's free AI-powered Vitamin B12 Deficiency symptom checker to assess your symptoms quickly, and follow up with a qualified healthcare professional for proper testing.

Most importantly, speak to a doctor about any symptoms that feel severe, persistent, or life-threatening. Early evaluation and treatment can prevent long-term complications and may improve your chances of a healthy pregnancy.

Your body—and your future fertility—deserve that attention.

(References)

  • * Florou PG, et al. Coenzyme Q10 supplementation and its effect on oocyte quality and fertility outcomes in women with diminished ovarian reserve: A systematic review and meta-analysis. J Assist Reprod Genet. 2020 Aug;37(8):1801-1809.

  • * Bentov Y, et al. Coenzyme Q10 and ovarian response: novel insights into the applications of the "energy vitamin" for fertility. Fertil Steril. 2017 Mar;107(3):813-817.

  • * Akbari A, et al. Coenzyme Q10 and female fertility. Int J Reprod Biomed (Yazd). 2022 Dec 15;20(12):1075-1084.

  • * Saccone G, et al. Coenzyme Q10 in the Treatment of Infertility: A Systematic Review. J Reprod Immunol. 2020 Jan;137:103064.

  • * Ben-Meir A, et al. Coenzyme Q10 reduces oocyte oxidative stress and improves mitochondrial function and developmental competence. Fertil Steril. 2015 Mar;103(3):821-828.e2.

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