The 60-second summary
Folic acid is the clear standard when trying to conceive. Vitamin D is sensible if a deficiency is likely or proven, not as a blind high-dose experiment. CoQ10 is optional, expensive and the evidence is mixed; if anything it may have a role in certain assisted reproduction settings rather than as a general booster.
- Folic acid: yes, start early and take consistently.
- Vitamin D: targeted, ideally after risk assessment or testing.
- CoQ10: if used at all, use for a limited time and with realistic expectations.
Why it’s easy to overdo supplements when trying to conceive
Many people reach for supplements because it gives a sense of agency. That is understandable, but it has a downside: the bigger the stack, the more likely overlaps, unnecessarily high total doses and false reassurance become.
Good supplement decisions follow a simple logic. First the standard, then risk factors, then diagnostics. Everything else quickly becomes a subscription that doesn’t answer a clear question.
Folic acid: the standard that really matters
Folic acid has the clearest evidence base. It does not aim to provide a vague boost to fertility but to support very early developmental stages at a time when many do not yet know they are pregnant.
It is recommended to take 400 µg folic acid daily when trying to conceive, ideally starting at least four weeks before pregnancy and continuing until the end of the first trimester. Guidance: folic acid when trying to conceive
Typical mistakes that matter more than the brand
- Starting too late and hoping a few days will make up the difference.
- Taking it irregularly because you do not notice an immediate effect.
- Buying a prenatal but not checking how much folic acid it actually contains.
- Using higher doses without a clear medical reason.
If you have particular risk factors, take certain medicines or have pre-existing conditions, recommendations may differ. In that case a medical assessment is sensible before increasing the dose yourself.
Vitamin D: sensible, but rarely a blind long-shot
Vitamin D is often marketed as a fertility booster. In practice it is primarily about deficiency. It can be sensible if supply is likely to be low, and unnecessary if you are already adequately supplied.
Health guidance emphasises that reference intake values are particularly relevant when the body’s own production from sunlight is reduced. That is a useful reminder why season, daily routine and time spent outdoors should factor into the decision. Reference values for vitamin D
When vitamin D is more likely to be relevant
- Long periods with little sun exposure, especially in winter months.
- Daily life predominantly indoors with rare outdoor time.
- Individual factors or medical conditions that make a low level more likely.
Avoid very large single doses given at intervals of days or weeks as a shortcut. Health authorities warn that such bolus doses can carry health risks, especially without clear indication and monitoring. Risks of high single doses of vitamin D
CoQ10: what it’s promoted for and what you can realistically expect
CoQ10 is often promoted with arguments about cellular energy and antioxidants. From that it is a small step to claims that CoQ10 generally improves egg quality or increases pregnancy chances. That sounds plausible but is not well supported as a general recommendation.
In studies CoQ10 mainly appears as a possible option in certain assisted reproduction contexts. A systematic review with meta-analysis found hints of benefit for some outcomes in ART settings, while evidence remains limited by study design and comparability. PubMed: CoQ10 and outcomes in ART
When CoQ10 may at most make sense
- As a time-limited option if ART is planned and you accept the uncertainty.
- When budget, tolerance and expectations align.
When CoQ10 is less appropriate
- When you intend it to replace diagnostics or medical assessment.
- When taking it becomes a must-do that creates pressure.
- When you combine multiple products and total doses become unclear.
A useful reality check is: if a product sounds like a must despite mixed data, it is usually marketing, not a standard of care.
Other supplements: what is often sensible and when it’s marketing
After folic acid, vitamin D and CoQ10, the next recommendations often come from social media or forums. Many have a plausible core, but they are quickly generalised. What matters is whether you have a clear situation that makes the supplement relevant.
Iodine
Iodine is often a relevant topic because requirements increase in pregnancy and breastfeeding. At the same time: with thyroid disease, iodine should be managed by a clinician, not self-medicated.
Iron
Iron is frequently promoted across the board. It is mainly sensible in proven deficiency or anaemia. Without evidence, high-dose supplementation is more likely to cause side effects than benefit.
Vitamin B12
B12 is particularly relevant for those on a vegan diet. Reliable supplementation is usually necessary then. For mixed diets it depends more on individual factors, and a check can bring more clarity than buying blindly.
Omega-3, DHA, choline
These nutrients are heavily marketed but are rarely the first lever to pull. For many people the pragmatic approach is to check diet and only supplement targeted gaps rather than automatically starting the next stack.
Zinc, selenium, antioxidant complexes
Here especially: more is not automatically better. Individual trace elements can be important for genuine deficiencies; as a blanket booster they are often oversold, and overdoses are possible.
Inositol and other specialised products
Such products can be discussed for certain diagnoses, for example in PCOS. Without a diagnosis and a plan for how to evaluate the effect, they quickly become expensive noise.
Myths and facts: the common errors in thinking
Most myths are not completely wrong, just too coarse. They turn a possible association into a guarantee. That leads to frustration and unnecessary expense when trying to conceive.
- Myth: The more supplements, the better. Fact: The more you combine, the greater the risk of overlaps, side effects and unclear total doses.
- Myth: High dose works faster. Fact: For some nutrients risks increase faster than benefit, especially without monitoring.
- Myth: An expensive product is automatically high quality. Fact: Price is not proof of quality and does not replace clear labelling.
- Myth: CoQ10 is mandatory. Fact: It is optional and the evidence is mixed, especially outside clear ART contexts.
- Myth: Vitamin D always helps. Fact: It helps mainly when supply is actually low.
- Myth: If I supplement I don't need diagnostics. Fact: If pregnancy does not occur, investigation is often more effective than further products.
Minimal plan instead of a stack of pills
A good plan is small, clear and sustainable. It reduces complexity rather than increasing it.
- Base: folic acid consistently.
- Targeted: vitamin D only with risk or proven deficiency, no high-dose experiments.
- Optional: CoQ10 time-limited, if in an ART context and expectations are realistic.
If you want to add more, state the reason in one sentence beforehand. If you cannot, the addition is often marketing rather than medicine.
Safety: overdosing, interactions, false reassurance
The greatest risk is seldom an acute emergency. More common are cumulative overdoses over time, unclear combinations and a deceptive reassurance that replaces diagnostics or lifestyle changes.
- Fat-soluble vitamins can become problematic at high cumulative amounts.
- Multiple products taken together increase the risk of unintentionally reaching very high total doses.
- If you have chronic illness or take regular medication, discuss new products beforehand.
A practical safety check is to place the labels of all products side by side and roughly add up the total dose of each nutrient.
Legal and regulatory context
Dietary supplements are generally treated as foods rather than medicines. They are not authorised like medicines before being sold, and initial responsibility for legal compliance lies with the manufacturer or importer.
Authorities explain the classification and central rules around dietary supplements, including notification procedures before placing products on the market. Food supplement regulation and guidance
If you buy internationally, rules, controls and permitted compositions can vary significantly by country. That’s not a reason to panic, but it is a good reason to be cautious with extreme doses and dubious health claims.
When testing is more useful than supplements
If trying to conceive remains unsuccessful for a long time, the question is rarely which supplement is missing. More often it is whether there is an identifiable cause that can be treated specifically.
This is especially true with cycle irregularities, severe pain, known diagnoses, after recurrent miscarriages or when time is an important factor. In such situations a structured medical plan usually achieves more than the next purchase.
Conclusion
Folic acid is the standard and worth starting early and taking consistently. Vitamin D is sensible when deficiency is plausible or proven, not as a high-dose experiment. CoQ10 is optional and rather a conscious choice under uncertainty than a requirement.
When you build a plan, keep it small, transparent and sustainable. That is often more helpful in practice than any stack of pills.
Note on add-ons: In fertility medicine many additional offers and supplements are discussed as having limited evidence. The HFEA classifies many add-ons as not sufficiently evidence-based for routine use and calls for transparency about benefits and risks. HFEA: Treatment add-ons
