Folic acid supplementation before and during early pregnancy prevents neural tube defects. The evidence is unambiguous — a Cochrane review of five randomised controlled trials found that periconceptional folic acid reduces the risk of neural tube defects by approximately 70%.
Yet uptake in the UK remains stubbornly incomplete. NHS Digital maternity data indicates that fewer than a third of women take folic acid before becoming pregnant, a figure that has barely changed in a decade. With nearly half of pregnancies in England unplanned, the pharmacy counter is often the earliest — and sometimes the only — opportunity for this conversation.
The government's renewed Women's Health Strategy, announced on 15 April 2026, includes commitments to improve preconception health advice. Pharmacy is central to delivering on that promise.
The recommendation
NHS guidance is straightforward:
- 400 micrograms (0.4 mg) daily from the point of trying to conceive until the end of week 12 of pregnancy
- 5 milligrams daily for women at higher risk of neural tube defects (see below)
- Ideally started at least 3 months before conception to build adequate folate levels
The 400 µg dose is available without prescription from any pharmacy as a single-ingredient supplement or as part of a pregnancy multivitamin. The 5 mg dose is prescription-only.
Who needs the higher dose?
The NICE guideline on antenatal care (NG201) specifies that the 5 mg prescription dose should be offered to women who:
| Higher-risk group | Reason |
|---|---|
| Have had a previous pregnancy affected by a neural tube defect | Recurrence risk is 10–20 times higher |
| Have a partner with a neural tube defect or family history | Genetic risk factor |
| Are taking antiepileptic medicines (especially valproate, carbamazepine, phenytoin) | These medicines are folate antagonists |
| Have coeliac disease or other malabsorption conditions | Reduced absorption of dietary and supplemental folate |
| Have diabetes (type 1 or type 2) | Associated with increased NTD risk |
| Have a BMI over 30 | Observational data associates obesity with higher NTD risk |
| Have sickle cell disease or thalassaemia trait | Often on folate supplementation already; dose should be reviewed |
Pharmacy teams who identify a woman in one of these groups during a folic acid purchase should recommend a GP appointment to arrange the prescription-strength dose.
What about methylfolate?
Some supplements marketed for pregnancy contain L-methylfolate (5-MTHF) instead of folic acid, with claims that it is "more bioavailable" or necessary for women with MTHFR gene variants. The evidence does not support switching from folic acid to methylfolate for routine NTD prevention:
- The landmark RCTs demonstrating NTD prevention all used folic acid, not methylfolate
- MTHFR variants are common (approximately 10% of the UK population are homozygous for C677T) but there is no RCT evidence that these individuals need methylfolate rather than folic acid
- NICE, RCOG and NHS guidance all recommend folic acid, not methylfolate
- Methylfolate supplements are substantially more expensive
Pharmacy teams can reassure women that standard folic acid 400 µg is the evidence-based choice for the general population.
Fortification: what changed
In September 2021, the UK government announced mandatory fortification of non-wholemeal wheat flour with folic acid, following decades of debate. Implementation has been phased, and by 2026 the measure is expected to prevent an estimated 150–200 neural tube defect-affected pregnancies per year.
However, fortification provides a lower dose than supplementation and does not replace the recommendation for women to take folic acid tablets when planning pregnancy. Pharmacy teams should make clear that flour fortification is a population-level safety net, not a substitute for individual supplementation.
The pharmacy consultation
Folic acid counselling opportunities arise in several pharmacy settings:
- Emergency contraception supply — the post-consultation conversation is an opportunity to discuss folic acid if the woman is considering future pregnancy
- Pregnancy test purchases — if the test is positive and the woman has not been taking folic acid, start immediately
- Repeat dispensing for antiepileptics — women of childbearing age on valproate, carbamazepine or phenytoin should be reminded of the 5 mg requirement at every dispensing contact
- General vitamin counter enquiries — staff should be confident in recommending single-ingredient folic acid over expensive "fertility blend" supplements with no additional evidence base
Other preconception supplements
Folic acid is the only supplement with robust RCT evidence for preventing birth defects. Other commonly purchased preconception supplements have weaker evidence:
| Supplement | Evidence for preconception use |
|---|---|
| Vitamin D | NHS recommends 10 µg/day for all UK adults year-round; important in pregnancy but not specifically preconception |
| Iron | Not routinely recommended before pregnancy unless deficient |
| Iodine | WHO recommends adequate intake; UK dietary intake may be marginal in some women. Pregnancy multivitamins often include 150 µg |
| Omega-3 (DHA) | Some evidence for fetal brain development; no evidence for preconception benefit |
Data context
PharmSee tracks 1,742 active pharmacy vacancies across England, including roles where preconception advice falls within the pharmacist's consultation scope. The workforce is under pressure, but brief, targeted folic acid conversations — particularly when triggered by a related purchase — require seconds rather than minutes and carry outsized public health impact.
For local pharmacy services including pregnancy-related consultations, use PharmSee's pharmacy search.
Caveats
Neural tube defect prevention data is drawn from Cochrane systematic reviews and the MRC Vitamin Study. Uptake figures are from NHS Digital maternity statistics. Flour fortification implementation timelines are from the Department of Health and Social Care. PharmSee does not track supplement sales or preconception consultation rates.
Sources: Cochrane Systematic Reviews (De-Regil et al.), NICE NG201 Antenatal Care, NHS Digital Maternity Statistics, RCOG guidelines, DHSC flour fortification policy, PharmSee vacancy database (April 2026), BBC News (15 April 2026).