to be an association between higher body mass indices and in women with bigger babies and the incidence and severity of striae. Also, younger women seem to be at higher risk of developing striae during pregnancy. The prevalence and severity of striae gravidarum varies among populations. The current literature suggest that in the general population of the US, there is a 50%-90% prevalence of striae associated with pregnancy, partly as a result of the normal hormonal changes of pregnancy and partly due to stretching of skin fibers. Many women experience striae gravidarum during their first pregnancy. Nearly 45% percent of women develop striae gravidarum before 24 weeks of gestation. Many women who develop lesions during the first pregnancy do not develop them during later pregnancies. Genetic factors such as genealogy and race also seem to be predictive in the appearance of striae. Prevention Collagen and elastin are proteins in the skin that contribute to the skin's strength, resilience, flexibility, and help skin that has been stretched to recover its original state. Boosting the production of collagen and elastin helps prevent stretch marks from occurring. Stretch marks can also derive from nutritional deficiencies. Consuming foods that contribute to the skin's health, such as zinc-rich foods, foods high in vitamin A, C, D, and protein rich foods, can help suppress stretch marks. A systematic review has not found evidence that creams and oils are useful for preventing or reducing stretch marks in pregnancy. The safety in pregnancy of one ingredient, Centella asiatica, has been questioned. Evidence on treatments for reducing the appearance of the scars after pregnancy is limited. Treatment There are no clearly useful treatments for stretch marks, although there are many different suggestions on how to remove them or lessen their appearance. Various efforts that have been tried including laser treatments, glycolic acid, and microdermabrasion. Tretinoin (0.1% w/w), which is a retinoid, has found to be effective on early stretch marks in several studies. Hyaluronic acid also improves the appearance of stretch marks. Topical tretinoin is categorized by the FDA as a known teratogen (causing malformations in fetuses) in animals, without adequate human studies on safety in pregnancy. Carboxytherapy is a known procedure; however, there is a lack of evidence to support how effective it is. History Since ancient times, pregnant women have sought remedies to prevent stretch marks during pregnancy. Both ancient Greeks and Romans used olive oil, while