Homocysteine: the overlooked fertility marker

Homocysteine is a type of amino acid — a temporary "waste product" naturally produced by your cells when they metabolise proteins. In a well-functioning system, this waste product would be immediately recycled and converted into useful substances, in particular through the action of key vitamins such as vitamins B9 and B12.

The problem occurs when this recycling process breaks down. Instead of being eliminated, homocysteine accumulates in the blood. At high levels, this waste product becomes toxic to the body, particularly to the walls of blood vessels.

Why can a high level be harmful to fertility?

A high homocysteine level (or hyperhomocysteinaemia) is not without impact on conception or pregnancy. Science has established clear links between this marker and certain difficulties in conceiving [1]:

• Implantation difficulties: As it accumulates, homocysteine weakens the walls of blood vessels. The body responds by forming micro-clots that can reduce blood flow to the uterus and the endometrium. This less well-perfused environment is less conducive to implantation and the healthy development of the embryo.
• Risk of early miscarriage: For the same reasons, poor vascularisation of the developing placenta can compromise the exchanges between the mother and the embryo, which increases the risk of early miscarriage.
• Decline in egg quality: A high homocysteine level also reflects significant oxidative stress in the body. This inflammatory state can affect the quality and maturation of eggs.

But why does this recycling system become blocked? Most often, the answer is genetic: the MTHFR gene mutation.

Behind this term lies a very common genetic variation, thought to affect 30 to 40% of the population to varying degrees [2]. The MTHFR gene plays a central role in the production of an enzyme that converts vitamin B9 into its active form, which is directly usable by the body.

In people carrying this mutation, the MTHFR enzyme is less effective. As a result, even when taking care to supplement with folic acid, your body may struggle to convert it. Unable to perform its role correctly, unconverted folic acid then accumulates without being able to recycle homocysteine, causing its levels to rise.

Understanding the difference between folic acid and methylated folates is essential, particularly for women who are trying to conceive.

• Folic acid: This is the synthetic form of vitamin B9, found in the majority of prenatal supplements. It is not active and needs to be converted by the MTHFR enzyme before it can be used. For women who carry the MTHFR gene mutation, it is therefore of little or no benefit.
• Methylated folates (or 5-MTHF): This is the already-active form of vitamin B9. It is "ready to use," as the body can utilise it immediately, without needing to convert it via the MTHFR enzyme. It therefore makes it possible to bypass potential genetic barriers and effectively lower homocysteine levels. The best pregnancy food supplements contain this form. 

At Jolly Mama, we know that every woman has her own individual needs. Since it is difficult to know whether you carry the MTHFR mutation without a specific test, we have chosen to apply a precautionary principle to ensure maximum efficacy.

That is why we created Folates Mama. Our formula contains no standard folic acid, but only the active and bioavailable form (methylfolate), absorbed by 100% of women, whether or not they carry the mutation. Combined with vitamin B12, Folates Mama gives your body the right tools to prepare an optimal environment for your pregnancy.

Want to make sure you don't miss anything? Jolly Mama also offers a range of prenatal multivitamins (Bump Essentials, Bump Powder or Baby Bump), containing many vitamins including B9 and B12. Be careful not to combine Folates Mama with these multivitamin formulations to avoid any risk of overdose!

Taking back control of your fertility means knowing which steps to take, and taking them as early as possible.

• Measure your levels: Speak to your GP or gynaecologist. A simple blood test can measure your homocysteine levels. While the reference values in the general population range between 5 and 15 µmol/L, the ideal is to aim for a level below 8–10 µmol/L to optimise your chances of conception. Bear in mind, however, that a good homocysteine level can, in some cases, be accompanied by a functional folate deficiency. The accumulation of unmetabolised folic acid can block cell receptors and prevent folates from entering the cells.
• Pay attention to your diet: Prioritise foods rich in natural folates, such as green leafy vegetables (spinach, lamb's lettuce, rocket), legumes (lentils, chickpeas), citrus fruits and eggs.
• Choose the best fertility supplement for women: Opt for a food supplement containing folates in their methylated form (5-MTHF) for optimal effectiveness.

The path to parenthood can sometimes feel long and complex. In this context, understanding the mechanisms at play is an important step. Homocysteine is one of the most invisible — and most easily corrected — causes of difficulty conceiving. In just a few months, with the right form of vitamin B9, you can give yourself every chance of preparing the most nurturing nest for your baby!