Hypergalactia is a congenital developmental abnormality. During embryonic development, there are 6-8 pairs of locally raised mammary primordia from the armpit to the ventral part of the inguinal line. With the increase of gestational age, except the surface cells of a pair of mammary glands in the chest continue to develop, the others gradually shrink and disappear. If it does not disappear, or even continues to develop, it will form accessory mammary gland-polygalactia.
Polynipple malformation is a kind of breast malformation, a congenital disease and a stage of human evolution. For some reason, there are defects in the evolution and development of embryos in the mother. Specifically, some women have multiple nipples in the chest and abdomen, which is the most harmful and unsightly, not only causing troubles to patients' lives, but also affecting patients' psychology. Patients may also have very intense pain during breastfeeding. And in some cases, it may cause breast cancer, which is more dangerous.