Stretch marks are very common, with at least half of all pregnant women developing them at some point during pregnancy. They are most common on the belly, as this is where there is the most stretch of the skin, but they are also very common on the breasts, buttocks, and thighs. Unfortunately, there is no guaranteed way to prevent stretch marks. They are largely determined by genetics, so if your mom or sister has stretch marks then you are much more likely to get them. Save your money as none of the multitudes of creams and oils on the market have been shown to be effective at preventing stretch marks. The only thing that you can do to try to prevent the development of stretch marks is to gain no more than the recommended amount, in most cases this is 25 to 35 pounds, and to do it slow and steadily. If you happen to be carrying multiples you are more likely to get stretch marks. If you do happen to develop stretch marks rest assured that they usually become much less noticeable as the deep purple or reddish color slowly fades to a more silvery color. Be sure to address your questions with your obstetrician at your next appointment.