It is possible to get pregnant, and pregnancy has no effect on the fetus. However, the higher estrogen level in the body during pregnancy may aggravate the symptoms of breast enlargement, which means that the mass of breast enlargement may increase and the breast swelling and pain may worsen. Although the cancer rate of mastocytosis is low, one should be alert to the higher hormone levels in the body during pregnancy and the greater changes in the internal environment. Some people say that the symptoms of breast enlargement may be relieved after childbirth, mainly because estrogen secretion decreases after birth and lactogen dominates, which feedback inhibits the secretion of estrogen. So the pain is reduced.