The possible clinical reasons for babies not growing hair after shaving include hereditary hair deficiency, scalp damage during shaving, and nutritional deficiencies. 1. Hereditary hair deficiency: If the parents of the baby have a type of baldness gene, it is very likely that the baby’s hair will be more difficult to grow after shaving, but this is a rare case. 2. Scalp damage when shaving: this is the most common cause of hair growth difficulties in infants, clinical parents are not recommended to shave the newborn’s fetal hair, which will grow and develop naturally. If the scalp is accidentally damaged during the shaving process, the hair follicles will most likely be damaged and unable to grow back. 3. Nutritional deficiencies: the difficulty of hair growth may also be the baby’s own intake of nutritional deficiencies, parents are advised to strengthen the newborn’s nutritional supply. The baby after shaving the fetal hair does not grow, there may be other reasons, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.