Oh-Baby-The-Subtle-Art-of-Photographing-a-Newborn-Photo29. When can I cut my baby’s nails? Baby nails seem to grow at a faster speed than we can find our baby clippers. You do have to wait at least two weeks to cut them for the first time because they are actually paper thin and very sensitive. To avoid scratching, I’ve dressed my babies with onesies where the sleeves fold out into mittens.