Both nipples are sore, there may be several conditions: 1, nipple cracking. If the baby is not sucking the correct way or nipple cracking during breastfeeding, it will lead to nipple cracking, thus causing nipple pain. 2, trauma or tight underwear. If the breast has been impacted, may cause nipple pain, you can first observe, you can towel hot compresses. If the lingerie is too tight and the nipple is in a tightened state for a long time, you can change the appropriate lingerie. 3. Breast cancer. It is recommended to consult a regular hospital for breast ultrasound to detect breast cancer. 4. Allergy. If the quality of underwear is too poor, it may cause nipple skin allergy, pain and itching, so the treatment requires changing underwear and taking oral Xanthemin anti-allergy.