A biodegradable hydrophilic binder fiber. These fibers may be produced by co-spinning an aliphatic polyester material in a side-by-side configuration with a polylactide polymer to obtain a fiber with improved material attributes. A multicarboxylic acid may be incorporated into either or both components of the fiber. The aliphatic polyester polymer may be selected from a polybutylene succinate polymer, a polybutylene succinate-co-adipate polymer, or a blend of these polymers. The biodegradable bicomponent fiber exhibits substantial biodegradable properties, yet has improved thermal stability and has significantly reduced shrinkage. The bicomponent fiber may be used in a disposable absorbent product intended for the absorption of fluids such as body fluids.