Stretch marks--the reddish purple lines on your skin that eventually fade to silvery white--aren't usually a serious problem, but they can be unsightly, especially when they're fairly new and still brightly colored. There's no way to get rid of stretch marks; treatments like chemical peels and microdermabrasion can make them less noticeable, but they never completely go away. There are several causes for stretch marks, some of which you might not be able to avoid.
Pregnancy
Many women get stretch marks on their bellies, hips and thighs during pregnancy, especially during the rapid growth that takes place during the third trimester. Pregnancy hormones may play a role in which women get stretch marks, suggests the Mayo Clinic, but it's the stretching of the skin that accompanies your baby's growth that has the biggest effect.
Puberty
Just as stretch marks can accompany the rapid, significant physical changes of pregnancy, they may appear on teenagers during puberty as their bodies undergo considerable physical changes. It's common for adolescents to get stretch marks during major growth spurts as their skin stretches to accommodate their new size.
Weight Gain
Sudden or sustained weight gain can also cause stretch marks, because your skin must stretch as you add pounds. Stretch marks are common in obese people and more common for people who gain weight rapidly than for people whose weight gain occurs at a steady pace, according to MedLine Plus.
Medications
Certain medications may interfere with your body's collagen production, causing stretch marks to appear if you use the medications for a long period of time. Corticosteroids--whether taken topically or orally--can cause stretch marks if you overuse them.
Medical Conditions
Though it's rare, if you notice the appearance of stretch marks when you're maintaining a normal weight, it could be a symptom of a more serious medical condition. Cushing syndrome, Ehlers-Danlos syndrome, Marfan syndrome and adrenal gland diseases are all serious medical conditions that can cause you to develop stretch marks.
