Male baby lower red and swollen, common factors are mosquito bites, circumcision, scrotal contusion, etc. Parents can choose under the guidance of the doctor general care, medication and surgical treatment. 1. Mosquito bites: male babies are prone to redness and swelling after being bitten by mosquitoes and insects on the lower side. For this situation, generally do not need special treatment, usually will be relieved by itself, pay attention to local cleanliness can be. 2. circumcision: if the baby boy circumcision is serious, the foreskin scale and other dirty things can not be discharged in time. After accumulating for a long time, bacteria will grow, thus appearing red and swollen down there. Generally, local disinfection and anti-infection treatment can be taken, such as iodine povidone disinfection, and if necessary, topical mupirocin ointment can be applied as prescribed by the doctor to alleviate the symptoms. 3. Scrotal injury: babies kicked or scratched during play can lead to scrotal injury, resulting in redness and swelling of the lower side. If it is a closed injury and the testicles are not damaged, anti-inflammatory and symptomatic treatment can be carried out. If there is a serious closed injury or open injury, surgical treatment is needed. There are other reasons for the redness and swelling of the baby’s lower side, it is recommended to take the baby to the hospital for examination, to clarify the diagnosis, and to carry out relative treatment under the guidance of the doctor. The medication should follow the doctor’s instructions.