The answer is 5 years after the menstrual cycle stops. Postmenopausal bone lose occurs in women, 5 years after their menstrual cycle stops. Bone loss may occur with any indication within the body, bone loss is due to the silent disease known as “Osteoporosis”. People are not easily informed that they have Osteoporosis, until the time comes that their bones become very weak. A sudden strain, bump or fall may cause a fracture or even a vertebra to collapse, which is why it is advisable to intake medicine or supplements, such as milk to strengthen bones even after menstruation.