To rule out mastitis during breastfeeding, you can check by hand whether there is redness and swelling in the breast, whether the local skin temperature is elevated, and whether there is local pressure and pain. If you have these symptoms, you need to go to the hospital in time for examination, you can do breast ultrasound, and you need to treat breast inflammation in time, which is related to breast enlargement, more milk secretion, nipple cracking, and improper sucking. If you are breastfeeding for a long time, if your breasts are damaged by external forces or if you have milk stagnation, you are prone to breast disease. You should develop regular breastfeeding habits. If you have enough milk, you should discharge your breast milk in time to avoid breast milk rising. You can prepare a breast pump to prevent local inflammation caused by prolonged accumulation of milk in the breast. Nowadays, breast morbidity is very high, so it is better to have an ultrasound examination every year to avoid mastitis, breast cancer and other diseases.