When pregnant women are 6 weeks pregnant, due to the change of hormone level in the body, breast swelling and pain may occur, which is normal and no need to worry. Generally speaking, women’s endocrine levels will change accordingly after conception, the body’s estrogen and progesterone secretion gradually increase, the hormone level is higher at 6 weeks of pregnancy, estrogen promotes the gland’s ductal hyperplasia, and progesterone stimulates the gland’s follicular hyperplasia, which results in the increase of the gland’s volume, preparing for the pregnant woman’s breast milk production. At this time, pregnant women may experience swelling and pain, and a few pregnant women may also experience nodular hyperplasia, which are normal physiological phenomena. As the pregnancy grows, the swelling and pain can be gradually relieved. Pregnant women with breast swelling and pain during pregnancy do not need to worry too much, you can wear loose underwear, often clean the breasts, you can also carry out the appropriate massage, if the pain is unbearable or other abnormalities, you can go to the Obstetrics and Gynecology Department to consult the doctor, the doctor will give the appropriate treatment.