GUIDE
Hair dye is generally considered safe during pregnancy, especially after the first trimester. The amount of chemicals absorbed through the scalp is minimal.
Most research suggests that the chemicals in hair dye are not present in amounts that would pose a risk to a developing baby. ACOG does not advise against hair dye during pregnancy. That said, some people choose to wait until the second trimester or use alternative methods for extra peace of mind.
Be prepared from day one
The scientific evidence on hair dye during pregnancy is reassuring. Studies examining hairdressers (who have the highest occupational exposure to hair dye chemicals) have not found a consistent increase in birth defects, miscarriage, or other adverse outcomes compared to the general population.
The amount of chemical absorbed through the scalp during a typical hair coloring session is very small — far less than what would be needed to reach the fetus in any meaningful concentration. ACOG does not advise against hair dye during pregnancy, and most providers consider it safe, especially after the first trimester.
That said, no large, randomized controlled trial has specifically studied hair dye safety in pregnant people (for ethical reasons, one is unlikely). The current evidence is based on observational studies, occupational health data, and toxicology assessments of individual chemicals. This is why some providers recommend precautionary measures rather than blanket reassurance.
These precautions reduce your exposure even further and address the main theoretical risks: chemical absorption and fume inhalation.
| Method | Why It Is Safer |
|---|---|
| Highlights / foils / balayage | Dye does not touch the scalp, so absorption is negligible. One of the safest options. |
| Semi-permanent or demi-permanent dye | Contains fewer chemicals than permanent dye. Washes out gradually without peroxide or ammonia in most cases. |
| Vegetable-based dyes (henna) | Plant-based with no synthetic chemicals. Pure henna (100% Lawsonia inermis) is safe. Avoid 'black henna' which may contain PPD. |
| Ammonia-free hair color | Reduces fume exposure. Available at most salons and in box kits. |
| Color-depositing conditioners | Apply temporary color without harsh chemicals. Wash out gradually over several shampoos. |
Hair dye contains several chemicals, and understanding what they are can help you make informed choices. None of these chemicals, at the concentrations found in consumer hair products, have been shown to cause fetal harm when used as directed.
The dose makes the poison. At the concentrations and exposure durations typical of hair coloring, these chemicals are not present in amounts that reach the fetus.
Let your stylist know you are pregnant. Experienced stylists are accustomed to working with pregnant clients and can suggest techniques that minimize scalp contact (like foils, balayage, or root touch-ups with minimal overlap) and keep processing times shorter.
Pregnancy hormones affect your hair in noticeable ways. Many people experience thicker, fuller hair during pregnancy because estrogen extends the growth phase of the hair cycle. Your hair may also respond differently to color — it might take differently, process faster, or look slightly different than you expect. For more on how pregnancy hormones change your skin and appearance, see our pregnancy skincare guide.
After delivery, estrogen levels drop and much of the hair that was in the extended growth phase sheds at once. This postpartum hair loss (telogen effluvium) is normal and temporary, usually peaking 3-4 months after delivery.
This means that if you color your hair during pregnancy, you may notice the results are not quite what you expected. Doing a strand test before a full application can help you preview the result.
Hair dye is not on the list of things to worry about during pregnancy. The evidence supports its safety, especially with common-sense precautions like ventilation, gloves, and timing. If you want extra peace of mind, highlights or vegetable-based dyes are the lowest-risk options.
For other common safety questions, see our pregnancy-safe medications guide, our Tylenol during pregnancy guide, and our flying while pregnant guide. For a complete overview of prenatal care, check our prenatal visit schedule — it is a good time to ask your provider any safety questions that are on your mind.
This guide is for informational purposes only and is not a substitute for professional medical advice. Always consult your healthcare provider with any questions about your pregnancy.
