Whether male or female infants, 3 to 4 days after birth, the breast will be slightly enlarged, hard, red, sometimes there will be a small amount of yellowish-white nipple milk-like liquid, this situation is not pathological. This is due to the estrogen and lactogen in the mother’s body before the birth of the baby through the placenta into the baby’s body, stimulating the baby’s mammary glands to grow caused by the baby, after 2 to 3 weeks, from the mother’s hormones in the baby’s body will be gradually consumed, the breast will slowly return to the normal state. Therefore, there is no need to carry out any treatment, not to mention the need to squeeze, the baby’s skin is delicate, so as not to cause infection. In addition, due to the same reason, the vulva of the baby girl also has some redness and swelling, and even some discharge, which are not pathological. This article is published with the authorization of Dr. Guo Fengzhen, please do not reproduce without authorization.