Can I Dye My Hair While Pregnant?

One of the most common questions we get asked at Revive Hair Artists is whether it's safe to dye your hair during pregnancy. It's completely understandable to want to know — and the good news is that the answer, based on current NHS guidance and available research, is broadly reassuring. Here's everything you need to know, trimester by trimester.

What Does the NHS Say About Dyeing Hair During Pregnancy?

NHS guidance states that the chemicals in permanent and semi-permanent hair dyes are not highly toxic, and that most research — although limited — shows it is safe to colour your hair while pregnant. The key point is that your scalp absorbs very little of the dye, especially if it is healthy, meaning the chemicals are unlikely to reach the baby in significant amounts.

That said, the NHS does suggest you may want to wait until after the first 12 weeks of pregnancy, when the risk from chemical substances is lower. This is because the first trimester is the most critical period of foetal development — the baby's major organs, including the brain, heart, and spinal cord, are forming during this time. Waiting is a precaution rather than a strict instruction.

Is It Safe in the First Trimester?

The NHS guidance does not say you cannot dye your hair in the first trimester — it says you may wish to wait. The distinction matters. There is no strong evidence that colouring your hair in the first trimester causes harm, but because research in this area is limited (it is ethically difficult to conduct clinical trials on pregnant women), a cautious approach is sensible.

If you do choose to colour your hair in the first trimester, taking the precautions outlined below will minimise any potential risk.

Is It Safe in the Second and Third Trimester?

Yes — the consensus from the NHS, NCT, and Tommy's charity is that hair colouring is considered safe from the second trimester onwards. The risk from chemical exposure is lower after 12 weeks, and the vast majority of women who have coloured their hair during the second and third trimesters have done so without any issues.

Do bear in mind that pregnancy hormones can affect how your hair responds to colour — it may take the dye differently, become more or less absorbent, or react in ways you might not expect. Always do a strand test and a fresh patch test before any colour service, even if you have used the same product many times before.

Can You Bleach Your Hair While Pregnant?

Bleaching your hair during pregnancy is subject to the same general guidance as hair colouring. The NCT and NHS both indicate that bleaching is considered safe as long as precautions are taken, since your scalp absorbs very little of the product. However, bleach is a stronger chemical process than most colour treatments, so there are some additional things to consider:

• Opt for foils rather than scalp bleach — having your hair foiled means the bleach is applied to the hair shaft rather than directly onto the scalp, which significantly reduces any absorption of chemicals through the skin.
• Ventilation is especially important — bleach produces stronger fumes than standard hair colour. Always ensure the room is well ventilated.
• Tell your hairdresser you are pregnant — a good hairdresser will adjust the service accordingly and ensure you are comfortable throughout.

What Ingredients Should You Be Cautious About?

While most ingredients in professional hair dyes are present in very low concentrations, there are a few worth being aware of during pregnancy:

• PPD (para-phenylenediamine) — a common ingredient in permanent dyes that can be allergenic. Pregnancy can increase skin sensitivity, so a patch test is essential even if you have never reacted to it before.
• Ammonia — a strong alkaline chemical used to open the hair cuticle in permanent dyes. Not linked to foetal harm at normal usage levels, but its fumes can be unpleasant, particularly if you are experiencing morning sickness. Ammonia-free options are available.
• Parabens and phthalates — preservatives and plasticisers found in some hair products that are worth avoiding during pregnancy where possible, as they can have mild hormonal effects.
• Resorcinol — used in some permanent dyes. As with all ingredients, exposure at normal levels is low, but it is worth being aware of if you are choosing between products.

If you are concerned about specific ingredients, speak to your midwife or GP before your appointment. They will be able to advise you based on your individual circumstances.

Best Practices for Dyeing Hair During Pregnancy

Whether you are having a professional colour service or touching up roots at home, following these guidelines will help keep both you and your baby as safe as possible:

• Always do a patch test — pregnancy can change your skin's sensitivity significantly, even to products you have used for years. The NHS recommends doing a fresh patch test every time during pregnancy.
• Tell your hairdresser you are pregnant — this allows them to adapt the service, choose appropriate products, and ensure you are comfortable.
• Work in a well-ventilated area — open windows and doors to minimise inhalation of fumes, especially with bleach or ammonia-based colours.
• Leave the dye on for the minimum time — follow the manufacturer's instructions and do not exceed the recommended application time.
• Wear gloves if applying at home — this prevents unnecessary skin absorption and reduces the risk of contact dermatitis.
• Rinse your scalp thoroughly — once the dye is processed, rinse well to remove all product from the scalp.
• Consider highlights or balayage instead of all-over colour — techniques that keep colour away from the scalp reduce any risk of absorption entirely.

Are There Safe Alternatives to Chemical Hair Dye During Pregnancy?

If you would prefer to avoid chemical dyes altogether during your pregnancy, there are some alternatives worth considering:

• Pure henna — the NHS specifically lists pure vegetable dyes such as henna as a safe alternative during pregnancy. Note that this applies to pure henna only — "black henna" and many compound henna products contain PPD and should be avoided.
• Semi-permanent and demi-permanent colours — these contain fewer chemicals than permanent dyes and do not use ammonia or peroxide to the same degree, making them a gentler option.
• Glosses and toners — applied away from the scalp, these can refresh colour and add shine with minimal chemical contact.
• Root touch-up sprays and powders — temporary, non-chemical options for managing roots between appointments.

What About Dyeing Hair While Breastfeeding?

The NHS notes that many women have used hair treatments while breastfeeding with no known negative results. The chemicals in hair dye are not considered to pass into breast milk in significant quantities. The same precautions — patch test, ventilation, minimal application time — apply as during pregnancy.

When Should I Speak to My Midwife or GP?

If you have any concerns about dyeing your hair during pregnancy, always speak to your midwife or GP before your appointment. This is especially important if you have a skin condition such as eczema or psoriasis (which can increase absorption through broken skin), if you have previously had an allergic reaction to hair dye, or if you are in the first trimester and feeling uncertain.

If you are based near Wolverhampton and would like to discuss the safest options for your hair during pregnancy, our team at Revive Hair Artists are always happy to advise — just give us a call before your appointment.

Frequently Asked Questions About Hair Dye and Pregnancy