Embodiments of the present invention are directed to occluder devices and methods for treating various target sites, such as the gonadal vein. For example, an occluder device according to one embodiment includes a tubular structure having proximal and distal ends and a preset, expanded configuration. The tubular structure is configured to be constrained to a reduced configuration for delivery to the target site and to at least partially return to the preset, expanded configuration within the target site when unconstrained. The preset, expanded configuration includes a plurality of expanded volume members and articulating members arranged in a repeating pattern with each articulating member coupling a pair of expanded volume members. In addition, at least one expanded volume member has a cross-sectional dimension that is larger than a cross-sectional dimension of a respective articulating member and that is at least as large as a cross-sectional dimension of the target site.