after how long in a pregnancy can a woman dye her hair
However, these doses are massive compared with the very low amount of chemicals a woman is exposed to when colouring her hair. Using hair dye when you're pregnant Many women decide to wait to dye their hair until after the first 12 weeks of pregnancy, when the risk of chemical substances harming the baby is much lower. If you're colouring your hair yourself, you can reduce the risk further by making sure you: 1  wear gloves. 2  leave the dye on for the minimum time. 3  work in a well-ventilated room. 4  rinse your scalp once the dye is applied.