Our hypothesis is that CGRP targeted migraine drugs will: a) decrease volumetric BMD and estimated failure load as measured by high resolution peripheral quantitative computed tomography (HRpQCT) at the distal radius and tibia; b) decrease areal BMD measured by dual energy X-ray absorptiometry (DXA) at the lumbar spine, total body, femur neck, and total hip; and c) decrease bone formation markers and increase bone resorption markers.CGRP(-R) antibody treatment: This is an observational study, and the protocol will not direct therapy. Decisions regarding medical therapy will be determined entirely by the subjects’ treating clinicians according to clinical standards. Patients may be enrolled receiving any of the following: erenumab (Aimovig), galcanezumab (Emgality), or fremanazumab (Ajovy). It is clinically important to determine whether there is musculoskeletal effects as a class, as well as for the subclasses of CGRP antibodies versus the CGRP receptor antibody (erenumab), or for individual agents in this class. The current grant mechanism does not cover a study large enough to assess whether effects of the different agents or subclasses have truly different magnitudes of musculoskeletal effect. If an effect is seen for a particular agent or subclass, we would then propose a future larger multicenter study to parse differences in magnitude of effect.