There is no pool of diving data to indicate that women are at any more or less risk of DCS or osteonecrosis when perimenopausal or post menopausal. Average menopausal age is 50, osteopoross usually starts between ages 60-65 and fractures average at 70-75. Osteonecrosis and osteoporosis have differing pathophysiologic mechanisms; osteonecrosis resulting from blockage of the small blood vessels of the bone, while osteoporosis comes from changes in cellular activity. Diving does not seem to have any effect on the changes in the osteoblasts and -clasts that occur with aging and diminished estrogen.
Good advice would be for the elderly female diver to dive conservatively so as to not add the risk of bubble damage to a porous bone from osteoporosis.