An apparatus, system or device and methods for applying one or more stimuli to an implantation, occlusive device, or embolization are described. The implantation can include a polymer or polymer composition such as a hydrogel and can be used for sterilizing a subject in need of contraception by occluding the vas deferens, fallopian tube(s), or uterus, but can also be used to occlude, in whole or part, any other body ducts or organs. The one or more stimuli can modify the occlusion so that is removed from the body lumen in situ, there by reversing the contraception or other effects of the occlusion.
