Acne on the forehead of pregnant women can be caused by improper diet, inadequate cleansing and endocrine disorders. 1. Improper diet: pregnant women eat more greasy, sweet food during pregnancy, this kind of food is easy to induce forehead acne. 2. Inadequate cleansing: If the patient does not pay attention to the cleansing of the facial skin during pregnancy, some oil and dirt will block the pores of the hair follicles, which may also lead to the appearance of acne on the forehead. 3. Endocrine disorders: pregnant women pregnant may produce tension, anxiety and other emotions, sebum secretion increases, bacteria in the face reproduction, the formation of acne on the forehead. It is recommended that pregnant women who have acne on the forehead should go to the hospital in time for examination and diagnosis, and choose the appropriate treatment under the guidance of the doctor.