Most women will experience breast swelling after about 45 days of pregnancy. Clinically, this is mainly due to the increase of estrogen and progesterone in the body after pregnancy, which will cause some corresponding symptoms in the breasts, which are all normal phenomena. Breast swelling, localized enlargement and nipple and areola coloring are normal physiological phenomena. During pregnancy, it is important to strengthen the local care of the breasts, wash the breasts with warm water every day, but do not use shower gel or soap to wash the nipple and areola, so as not to cause skin dryness. In addition, if the nipple has a mild inversion, you can use hot compresses and then gently pull the nipple every day, which will be conducive to breastfeeding the baby.