When does breastmilk get absorbed back into the body?

Breastmilk does not get "absorbed back" into the body in a traditional sense; instead, it is produced by the mammary glands in response to hormonal signals, primarily prolactin. After breastfeeding or pumping, any remaining milk can be reabsorbed by the body if not expressed, but this process is not a primary function. Generally, the body continually produces milk as long as there is demand through suckling or pumping, and the cycle of production and removal maintains milk supply.