Stretch marks occur most commonly due to weight change - either on gaining weight or loosing weight. it is also common after vigorous exercises and pregnancy. Stretch marks can be treated with dermaroller, fractional CO2 lasers, chemical peels and likewise. Remember combining treatment modalities help to achieve desired results earlier. Your dermatologist will decide a treatment plan for you after a consultation. Apart from active pharmaceutical medicines, a healthy diet and lifestyle is mandatory to achieve results.