Staining ... yes, after testing
If you are used to coloring, no problem, whatever the technique used. On the other hand, if you want to change products or if you want to change your color for the first time, try to check that the product does not react. The physiological changes in pregnancy make your body more sensitive to allergies. There is little reason to be worried, but as much follow the "procedure": apply a little product behind your ear and if no redness appears after the lapse of time indicated on the user manual ... color without fear.
You can opt for a color that fades as shampoos: it gives beautiful reflections. To change the shade or to hide some white hair, you will need a definitive color. As for wicks or sweeping, it is ideal for giving relief and light to hair a little dull. This method has the merit of not touching the scalp, the risk of irritation is therefore zero.
If you want to make this change in your bathroom, you do not have to worry: the products "home" that are available to you are numerous, more and more easy to use and they act quickly.