What are the causes of sagging breasts?

Physiological sagging of the breasts, common causes include
Sagging breasts after weight loss: mainly due to the sagging of fatty tissue and skin within the breasts after weight loss. It is mostly seen in young and middle-aged women.
Breast sagging after breastfeeding: After breastfeeding has stopped, due to the decrease in hormone levels, the ducts, glands and fatty tissues of the breast bladder atrophy, while the skin and supporting tissues are correspondingly more, thus leading to breast sagging.
Sagging breasts in the elderly: As the elderly age, the soft tissues of the breasts gradually atrophy, eventually leading to sagging breasts.
Pathological breast sagging is commonly caused by breast hypertrophy, an increase in the size of the breast caused by overgrowth, exceeding the normal ideal breast size by 50%, mostly accompanied by varying degrees of breast sagging.