We have recently observed an increased risk for vertebral fractures (VF) in a randomized controlled trial comparing the analgesic effect of vertebroplasty (VP) versus conservative treatment in symptomatic VF. The aim of the present study was to evaluate the risk factors related to the development of VF after VP in these patients. We evaluated risk factors including age, gender, bone mineral density, the number, type, and severity of vertebral deformities at baseline, the number of vertebral bodies treated, the presence and location of disk cement leakage, bone remodeling (determining bone turnover markers) and 25 hydroxyvitamin D [25(OH)D] levels at baseline in all patients. Twenty-nine radiologically new VF were observed in 17 of 57 patients undergoing VP, 72% adjacent to the VP. Patients developing VF after VP showed an increased prevalence of 25(OH)D deficiency (<20 ng/mL) and higher P1NP values. The principal factor related to the development of VF after VP in multivariate analysis was 25(OH)D levels < 20 ng/mL (RR, 15.47; 95% CI, 2.99–79.86, p < 0.0001), whereas age >80 years (RR, 3.20; 95% CI, 1.70–6.03, p = 0.0007) and glucocorticoid therapy (RR, 3.64; 95% CI, 1.61–8.26, p = 0.0055) constituted the principal factors in the overall study population. Increased risk of VF after VP was also associated with cement leakage into the inferior disk (RR, 6.14; 95% CI, 1.65–22.78, p = 0.044) and more than one vertebral body treated during VP (RR, 4.19; 95% CI, 1.03–34.3, p = 0.044). In conclusion, nearly 30% of patients with osteoporotic VF treated with VP had a new VF after the procedure. Age, especially >80 years, the presence of inferior disk cement leakage after the procedure, the number of cemented vertebrae, and low 25(OH)D serum levels were related to the development of new VF in these patients, with the latter indicating the need to correct vitamin D deficiency prior to performing VP.