After 3 years of ZOL , in women who have a TH t-score above -2.5 , no recent incident fracture and no more than one risk factor ( almost 55 % of the population ) , risk for subsequent fracture ( over three additional years ) is low if treatment is discontinued ( for MorphVertFx , average risk 3.2 % and for NVF , average risk 5.8 % ) .