Associate breasts are the extra breast tissue that appears in the human body in addition to the normal pair of breasts. In the embryonic period, there are 6 to 8 pairs of mammary glands in the two lines from the armpit to the groin, and all of them degenerate before birth except for the pair in front of the chest. If the developmental abnormality of the mammary gland primordia is not completely degraded, multiple breasts are formed. Associate breasts can appear as breast tissue without nipples, as both breast tissue and nipples, or as no breast tissue to nipples. Most of the secondary breasts are in the front of the armpit or under the armpit. Usually small, asymptomatic paramedian breasts do not require special treatment. If they are large and painful around the time of menstruation, surgical removal is recommended. The paratesticular breasts are also breast tissue, and when they are large, they may not only affect the aesthetics, but may also develop malignant tumors of the breast. If you suspect that you have paratesticular breasts, it is recommended that you consult a regular hospital and receive standardized treatment under the guidance of a doctor.