Many babies cry after vaccination, and generally consider the following factors: 1. Although babies are relatively young, their psychology is gradually starting to develop, and the hospital is an unfamiliar environment for them, which in itself can cause psychological tension, plus the pain caused by vaccination, which can lead to crying. The baby’s mother can actively divert her attention or hug the baby more to increase the sense of security, so that the baby can stop crying. 2. Different vaccines will have different effects on the body, and common vaccine reactions are fever; others will show gastrointestinal symptoms, rash and allergy. 3. other symptoms. This reaction will disappear within 2-3 days. If the baby cries for a long time, it is recommended to go to the hospital for consultation.