MTHFR mutations and recurrent miscarriages: is there a link?

Posted by Ema Smith on August 9th, 2018

By searching for information on regular miscarriages, you will probably encounter references to various unproven treatments. Researchers have many theories about the causes of recurrent miscarriages, but relatively few have scientifically proven treatments. In the meantime, doctors often test and treat the potential causes of recurrent miscarriages, which they feel have a solid theoretical basis and for whom they believe the potential treatment will not harm, even if it does not help.

The practice of testing genetic mutations falls into this category.

The current state of MTHFR

The researchers examined mutations in the MTHFR gene as a possible factor in recurrent miscarriages with rather mixed results. Some studies find that variations in the MTHFR gene increase the risk of miscarriage while others find no link. At present, a number of doctors do a best MTHFR test in sufferers with a history of miscarriage and suggest aggressive treatment to all who have MTHFR genetic mutations. Others never test MTHFR variants.

The context of MTHFR and miscarriage

MTHFR represents methylenetetrahydrofolate reductase. It is an enzyme involved in the metabolism of amino acids in the body. Mutations in the MTHFR gene can affect how a person's body treats homocysteine, an amino acid found in the blood. People with MTHFR gene mutations may have high levels of homocysteine, but not everyone with a mutation in the MTHFR gene is affected.

In addition, people with MTHFR gene mutations may have reduced the ability to metabolize folic acid and other B vitamins. Over the years, dozens of common and rare mutations in the MTHFR gene have been identified. Among the most common are mutations called C677T and A1298C, the former being often called the more problematic of the two.

A person may be either heterozygous or homozygous for either of these mutations in the MTHFR gene (heterozygote means that a person has had a copy of the mutation and the homozygous means that the person has two copies of the mutation). It is important to understand that mutations in the MTHFR gene are quite common: almost half of the US population may be at least heterozygous for a mutation in the MTHFR gene.

The debate: is MTHFR a risk factor for miscarriage?

In the best  MTHFR website that promotes MTHFR genes as a possible risk factor for possible miscarriage, the theory often focuses on the idea that, because MTHFR mutations can cause elevated homocysteine, which increases the risk of blood clots (although weakly), mutation of the MTHFR gene should be treated as Hereditary thrombophilia.

Many doctors believe that hereditary thrombophilia, such as Factor V Leiden, can increase the risk of miscarriage by creating tiny clots of blood that block the flow of nutrients to the placenta and thus include MTHFR genetic mutations in this category. However, hereditary thrombophilia is not universally accepted as a cause of recurrent miscarriage, this is a controversial topic. In fact, the only thrombophilia disorder with widely accepted treatment is the antiphospholipid syndrome.

To further add to the variability in the treatment of these mutations, some doctors believe in the treatment of heterozygous and homozygous women, while others treat only homozygous women. Other doctors do not test MTHFR genetic mutations at all because the link is far from proven conclusively. However, the doctors decide on to test homocysteine ​​instead and recommend therapies for women with high homocysteine ​​levels. However, other physicians (and probably the vast majority fall into this category) do not test either MTHFR or homocysteine, as none of the formally recommended treatments can reduce the risk of miscarriage.

In the meantime, if your doctor is treating you for an MTHFR mutation or a homocysteine ​​level, be sure to address your concerns about treatment. Similarly, if your doctor does not test mutations of the MTHFR gene, the reason is probably due to the lack of conclusive evidence of the value of doing so. But if you are concerned, it does not hurt to address the issue and hear your doctor's reasons behind his opinion.