NEW YORK (Reuters Health) - Women who smoke are more likely to begin menopause before the age of 45 years, which puts them at increased risk of osteoporosis and heart disease, Norwegian researchers report.Among a group of 2,123 women 59 to 60 years old, those who currently smoked were 59 percent more likely than non-smokers to have undergone early menopause, Dr. Thea F. Mikkelsen of the University of Oslo and her colleagues found. For the heaviest smokers, the risk of early menopause was nearly doubled.