The spots on the face during pregnancy are closely related to three factors: the change of hormone level, the exposure to UV rays and the choice of cosmetics. There are various hormones increase during pregnancy, which may cause pigmentation, the degree of depth and location is different for everyone. In addition, ultraviolet radiation can aggravate the spots on the face during pregnancy, so we should pay attention to reasonable sun protection. Because the ultraviolet rays of the sun will stimulate the secretion of melanin cells, which may cause the skin color to deepen and even various spots to appear. In addition, if cosmetics are not chosen properly, there is a possibility that some special ingredients, such as preservatives and metal elements, may cause serious skin reactions, so mothers-to-be should choose cosmetics with pure natural ingredients.