It's actually scarring caused by distension and minor trauma of dermis, due to rapid weight changes. Majority of the same reduces with time, but may not disappear completely. Electrotherapy agents like ultrasound and laser therapy can help in reducing the thickness and hardness and can help in making it lighter in feel and looks. But evidence for complete removal is lacking.
Health Tips
light massage with pure petroleum jelly after a bath helps in keeping the marks soft and supple.