What is a contraindication for using certain chemical treatments?

Chemical treatments can often involve strong substances that can affect not only the hair but also the overall health of the individual undergoing the treatment. When it comes to pregnancy, many healthcare professionals advise caution. This is due to the potential absorption of chemicals through the skin and the possibility of them affecting the developing fetus. Therefore, it is recommended to avoid certain chemical treatments during pregnancy to ensure the safety of both the mother and the unborn child.

In contrast, an oily scalp, previous hair dye, or dry ends generally do not pose the same level of risk as pregnancy. While these conditions may require different considerations or adjustments in the treatment process, they do not represent a direct contraindication that could affect the health of another individual. Thus, pregnancy stands out as a significant factor that necessitates avoiding certain chemical treatments.