I get asked about hair treatments all the time; unfortunately there isn't an easy answer. If pregnant women wanted to be research subjects to test product safety, we might have some safety data, but what mother-to-be would volunteer to be a guinea pig? And the results of animal studies don't always predict what happens in people.
Here are the facts:
- Hair dye, bleach, perms and relaxing solutions are all absorbed into the bloodstream to some degree.
- In animal tests, some of these solutions caused birth defects in offspring, but at much higher blood levels than you would see with normal use.
- There is no reason to believe that "natural" products are any safer than man-made ones. Plenty of toxins can be found in nature!
- Women have used hair products for decades, with no obvious problems in their babies.
- Highlighting, which doesn't touch the scalp, is probably safe throughout pregnancy.
So, now you know why recommendations are conflicting. I actually think what is recommended may have more to do with whether the "expert" is a worrier (better just avoid any possible exposure) or more low-key (no evidence of risk so don't worry) than with true safety data.
Here's what I think is a balanced view. Tell your doctor or midwife what you would like to use. Many experts recommend that you wait until after the first trimester to ensure that the baby's organs are formed before using anything that might pose even minor risk. Pregnancy can be hard on your body image, and if it makes you feel good to fix up, that has value too. You'll just have to collect information and then decide for yourself what is best.