MEDERMA Stretch Marks Therapy can be used by anyone with stretch marks due to Pregnancy, Puberty, Gym Workout and other hormonal changes. The most common cause of stretch marks are: – Pregnancy – as the skin stretches during this tenure. – Puberty – since the body undergoes hormonal changes, stretch marks may form. – Gym Workout – stretch marks are formed as a result of rapid weight gain or loss. – Syndrome – Marfan syndrome and adrenal gland diseases may also cause stretch marks.