Rapid Response To Teriparatide In A Postpartum Osteoporosis Case Associated With Nardroparine Treatment During Pregnancy

ABSTRACT Objective: Pregnancy-associated osteoporosis (PAO) is a rare condition characterized by back pain and vertebral fracture (VF) during late pregnancy and the early postpartum period. Methods: We report a case of PAO with multiple VFs in a woman treated with low-molecular-weight heparin (LMWH) nadroparine during her second pregnancy and the rapid response to teriparatide treatment. Results: A 29-year-old woman presented for severe back pain and inability to stand upright. The symptoms started shortly after delivery of her second baby. Starting with the second month of pregnancy, she was treated with nordroparine 3,800 UI/day. Magnetic resonance imaging showed multiple thoracic (T) and lumbar (L) VFs. Lateral vertebral assessment (LVA) showed mild T8 and T10 and moderate T12 and L1 VFs. Bone mineral density (BMD) measured using dual-energy X-ray absorptiometry (DXA) revealed very low scores for lumbar spine (T-score, -4.2 SD; Z-score, -3.6 SD) and femoral neck (T-score, -2.1 SD; Z-score, -1.6 SD). Teriparatide treatment 20 μg/day was started plus vitamin D and calcium. The serum concentration of bone formation markers increased significantly after the first month of treatment. After 6 months, the patient reports only occasional back pain and has no limitation to standing. DXA assessment showed a remarkable 12.1 and 3.6% increase in lumbar spine and femoral neck BMD, respectively. No new VFs were apparent on LVA. Conclusion: Prolonged LMWH treatment during pregnancy could cause PAO. Teriparatide treatment is highly efficacious in ameliorating symptoms, increasing spine and femoral neck BMD, and consequently preventing new VFs. Abbreviations: BMD = bone mineral density; DXA = dual-energy X-ray absorptiometry; L = lumbar; LMWH = lowmolecular- weight heparin; PAO = pregnancy-associated osteoporosis; T = thoracic; VF = vertebral fracture