What are the chances of getting stretch marks in pregnancy?

Common. The literature is varied but at least half of women will get stretch marks during pregnancy (striae gravid arum). However there are also reports that up to 90% of women will get stretch marks. Either way it is probably a 50-50 chance at best.
50 % There seems to be a genetic component so look at your mother or other women in your family. You can decrease your chances by keeping your skin well moisturized. If your skin is itchy, then you may need to apply more lotion or oil.

Related Questions

What will reduce my chance of getting stretch marks during pregnancy?

Possible. There are a number of factors that influence stretch marks. Some may be the amount of weight you gain, the natural state of your skin (dry versus oily) and genetic factors. Try to keep the skin lubricated, eat healthy, take your vitamins, and watch your weight gain. Read more...
Good diet. "stretch marks" are not strictly mechanical. They are really metabolic in character and often appear in obesity. A good natural food diet and some vitamin supplements help. The largest organ in the body is the skin. Thus it needs to be fed properly like all the other body organs.Ask your ob/gyn. Read more...
Moisture...... Stretch marks affect as many as 90% of all women. If your mother had stretch marks, you will probably get them as well. Avoid rapid weight gain or loss. Eat a healthy diet. Moisturize, moisturize, moisturize. Use a product with high concentrations of shea or cocoa butter, and massage it in 3-4 times a day. If you do get stretch marks, get treatment early for best results. Read more...