Redness on both sides of the outer lips of female babies may be caused by bacterial infections, pinworms and other causes, according to the different causes to formulate a treatment plan. 1. Bacterial infection: If you use diapers for a long time or don’t do a good job of cleaning the outer lips, it will lead to bacterial infection caused by moist skin on the outer lips, resulting in redness, swelling and pain. It is recommended that the baby be cleaned with warm water after each urination or stool, and then locally applied erythromycin ointment for sterilization, disinfection and anti-inflammatory treatment. 2. Pinworms: If the baby suffers from pinworms, it will lead to itching around the outer lips and anus, and the baby will get infected after scratching, thus causing redness, swelling and pain. It is recommended to use pinworm cream to apply to the affected area for deworming treatment. It is recommended to go to the hospital to see the clinician in time, and actively cooperate with the doctor for treatment. The above medications should be used under medical supervision.