Pregnant women sometimes find that, hair may become thicker, because high estrogen levels can slow down hair’s shedding process. However, when estrogen levels return to normal, hair shedding cycle will also return to normal.
Pregnant women may also experience hair texture changes - hair may become straighter or more curly. After baby is born, hair texture will return to its normal state. You may also see hair moisture changes - the hair may become more oily or drier. In this case, you need to change your shampoo and hair conditioner.
If you want hair coloring or perming, you need to consult your doctor. During pregnancy, you need to minimize chemicals entering scalp.