How MTHFR and A1298C May Be Contributing to Infertility – The 411

baby - MTHFR

What is the official name of the MTHFR gene?

The official name of this gene is “methylenetetrahydrofolate reductase (NAD(P)H).”

MTHFR is the gene’s official symbol.

What is the normal function of the MTHFR gene?

The MTHFR gene provides instructions for making an enzyme called methylenetetrahydrofolate reductase. This enzyme plays a role in processing amino acids, the building blocks of proteins. Methylenetetrahydrofolate reductase is important for a chemical reaction involving forms of the vitamin folate (also called vitamin B9). Specifically, this enzyme converts a molecule called 5,10-methylenetetrahydrofolate to a molecule called 5-methyltetrahydrofolate. This reaction is required for the multistep process that converts the amino acid homocysteine to another amino acid, methionine. The body uses methionine to make proteins and other important compounds.

Defective MTHFR Gene Linked to Fertility and Pregnancy Struggles

The B vitamin Folic Acid has been touted as the most important vitamin for the proper development of a baby in pregnancy. This is especially true for the first few weeks of pregnancy, when the spinal column is developing. Research shows that folic acid plays a critical role in preventing the neural tube defect, spina bifida. It is considered so important, that the March of Dimes has an entire campaign focused on educating the public about the importance of women in their childbearing years, getting the right amount of this vitamin daily.

What if your body has a genetic defect that makes it extremely difficult for your body to utilize folic acid properly, though? And how would you even know? For 1 in 4 people this is a serious reality and if left undiagnosed, may lead to a variety of pregnancy related issues including difficulties conceiving, unexplained infertility, elevated homocysteine levels, recurrent miscarriages, child with Down Syndrome, development of Autism, preeclampsia, postpartum depression, or even the development of chronic depression.

The Role of MTHFR in Utilizing Folic Acid and Folate

To begin, it is important to know that the MTHFR gene resides in each and every cell in the body. It is responsible for utilizing folic acid and producing the most active form of folate called methylfolate. People with the variant MTHFR C667T have a 40 – 60% decreased ability to produce methylfolate.

Why is Methylfolate so Important?
In the body, methylfolate starts an innumerable amount of critical enzymatic reactions. This impacts the body’s ability to produce a compound known as s-adenosylmethionine, SAMe for short. The body needs SAMe to produce CoQ10, carnitine and creatine, all of which play a critical role in the body’s ability to reproduce, not to mention maintain a variety of other body systems.

MTHFR C677T gene defect contributes to elevated homocysteine levels, which are commonly linked to recurrent miscarriages, as well as the other pregnancy related risks I spoke of previously.

How does MTHFR gene defect cause elevated homocysteine levels?
One by-product of SAMe is homocysteine. Methylfolate and methylcobalamin help to convert harmful homocysteine into the beneficial methionine, which in turn helps to produce SAMe, in a cycle that is never ending, as long at the body is producing methylfolate. In the case of MTHFR gene defect, homocysteine levels may rise to harmful levels due to the impaired ability to produce adequate amounts of methylfolate; impacting your ability to conceive, or harming an otherwise healthy pregnancy.

Other concerns with this wheel are that the body will poorly convert homocysteine to the powerful antioxidant glutathione, which helps protect the body from free radical damage. People with compromised antioxidant levels are more susceptible to oxidative damage due to stress and environmental toxins, thus increasing the risk for toxin build-up. In addition, people with MTHFR gene defect may have lower levels of SAMe, which has been shown to increase the development of depression and postpartum depression. SAMe is also plays an important role in immune system function, growth, repair and maintenance of cells, and is anti-inflammatory. All of these play a role in reproductive function and proper development of a baby in pregnancy.

Testing is Easy!

If you have been struggling to get pregnant, have experienced recurrent miscarriages or any of the other pregnancy related issues I mentioned previously, schedule an appointment with your doctor for a MTHFR genetic test and blood homocysteine level. This should be done before you try to get pregnant again.

Results Matter – Heterozygous or Homozygous?
There are different variations of the MTHFR gene defect. There are people with heterozygous (1 copy of C677T, passed on from one parent) and homozygous (2 copies of C677T, passed on from both parents) MTHFR mutations. Those with homozygous MTHFR C677T are often advised to take their folate requirements more seriously. Homozygous individuals need to avoid synthetic folic acid (see below for more info on this), they require more methylfolate supplementation than heterozygous individuals do, and their blood thinning requirements are greater, especially where a woman’s ability to get pregnant and carry to term is concerned. Before a successful pregnancy can be achieved, these considerations must be addressed.

What You Can Do if You Test Positive for MTHFR C677T

Although at first it feels quite scary and hopeless to be diagnosed with a genetic defect, this one is quite common. Fortunately there are things you can do at home to increase your chances of natural conception, carrying a healthy pregnancy to term, preventing postpartum depression and protecting your health overall, since MTHFR gene defect impacts many areas of health.

  • Eat organic, this will help reduce overall toxic load.
  • Avoid supplementing with synthetic folic acid, choose a whole food preconception multivitamin like Fertile Woman One Daily while trying to conceive and then switch to a whole food prenatal multivitamin like Baby and Me Multivitamin through pregnancy and breastfeeding. You may also want to ask your doctor about special prenatal vitamins that contain methylated folate or folinic acid.
  • Eat a diet rich in naturally occurring folate, such as uncooked dark leafy green vegetables, lentils, beans, liver, and avocado.
  • Take ONLY L-methylated folate, as the body will not absorb methylated folate.  ( is a great resource)
  • Avoid processed foods that are fortified with synthetic folic acid (homozygous), or strictly limit them (heterozygous).
  • Consider supplementing with carnitine, CoQ10 Ubiquinol, cod liver oil, probiotics and an antioxidant blend.
  • At each meal, eat a variety of whole foods and be sure to include a protein.
  • Make sure all the B vitamins you supplement are from a whole food source and provide the methylated form (active). For vitamin B6 this would be Pyridoxal 5-Phosphate or P5P; for Vitamin B12 this is methylcobalamin.
  • Avoid regularly consuming both black and green tea, as they may inhibit folic acid absorption.
  • Avoid antacids, these inhibit folic acid absorption as well.
  • According to Dr. Ben Lynch, an expert on MTHFR gene mutation, it is best to avoid birth control use, as this can block folate absorption.
  • For vegans, it is important to speak with your doctor about supplementing with the following, in addition to the above; methylcobalamin (active form of vitamin B12) and choline.
  • Find a good OB/Gyn or midwife to work with that is well educated in MTHFR gene mutation if you plan on getting pregnant. This will help you to maintain the continued support you need through pregnancy and lactation.


“The A1298C gene variant is found in the MTHFR gene. This gene produces an enzyme that is important in the metabolism of homocysteine, an amino acid.

We all have two copies of the MTHFR gene, one from each parent. People with two copies of the A1289C gene variant are referred to as homozygous. Having two variants/mutations, such as A1298C, can cause elevated homocysteine levels.

MTHFR deficiency, in the presence of elevated homocysteine levels, has been associated with a variety of health issues including an increased risk for venous thromboembolism (the formation of a blood clot in a vein), early onset cardiovascular disease, and adverse pregnancy outcome including fetal growth restriction, preeclampsia, miscarriage and placental abruption. However, these risks may not be increased in the presence of normal homocysteine levels. A blood test can be performed that measures plasma homocysteine levels.

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