Other factors include:

Amount of weight gainNutrition and hydrationRate of weight gainSkin elasticityUse of skin products (more for the health of skin)

If you do develop stretch marks, you may get them in places other than your belly. Here are a few places stretch marks can show up—some of which may be unexpected. Sometimes, you may notice that these start on one side your hips and move across to the other side in one big line. Other times, you will notice that these are two distinct areas of stretch mark. Having stretch marks on the sides is not something to worry too much about, these tend to be lighter. Remember, not everyone gets stretch marks everywhere. You can have breast growth and not get stretch marks, or you may have gotten breast stretch marks in puberty. You might also notice some on your legs. Near the knee is one common place. You can find them on the back side of the leg more frequently. Though stretch marks can stretch from the pregnant abdomen all the way to and through the pubic hair. It is also possible to have them start here and move to the inner thigh. Needless to say, these are easy to cover up!