Best dental clinic in Kovilambakkam - Amethyst Dental & Aesthetics Teeth Whitening: I am pregnant or nursing. Is it safe? Whitening is generally safe. The gel that we use is hydrogen peroxide, which converts to water upon activation. There are no studies that show any issues with a developing foetus during whitening. However, as the first trimester is usually a crucial period during pregnancy, we do advise caution during this time. There is no issue with doing whitening while nursing. Contact us Amethyst Dental & Aesthetics