Is it safe to get highlights when pregnant?

For the most part. By and large, highlights are relatively safe. However, there may be some products out there that have harmful chemicals. It is best to wait for hair highlights until after the first trimester. The first trimester is when the fetus is most vulnerable to harmful chemicals and substances. Try "greener" options for hair products-.
Yes. Make sure that you have your hair dyed in a well ventilated area. Otherwise it is considered safe.