A soft tissue filler comprising a biodegradable amino-acid derived polycarbonate-urethanes and methods of repairing soft tissue defects are provided. The biodegradable soft tissue filler comprises a porous scaffold that is the reaction product of: a) a divinyl oligomer component that comprises a carbonate-derived divinyl oligomer that is the reaction product of a lysine-derived diisocyanate, a vinyl coupling agent, and a polycarbonate and, optionally, an ether-derived divinyl oligomer, wherein the ether-derived divinyl oligomer is the reaction product of a lysine-derived diisocyanate, a vinyl coupling agent, and an ether; b) at least one anionic monomer; and c) at least one hydrophobic monomer. The molar ratio of (a):(b+c) is between about 1:≥21 and about 1:30, the soft tissue filler has a porosity of >75%; and a compressive moduli of between about 1 kPa and about 50 kPa.