What Are the Chances?
It's no surprise that fertility treatments boost your chances of having a bundle of kids, but you're also more likely to have multiples if...
- You already have children. Although researchers aren't exactly sure why, a woman's chances of having twins increase with each pregnancy.
- You're older. As you age, your body produces more follicle-stimulating hormone, which can cause your ovaries to "drop" several eggs during each cycle.
- You're overweight. A study in the journal Obstetrics and Gynecology found that women with a body mass index over 30 (180 pounds for a 5'5" woman, for example) are twice as likely to have fraternal twins as are thinner women. In addition, the study found that taller women (those over 5'5") are more likely to have fraternal twins than shorter women are.
- Multiples run in your family. (This is especially true on the mother's side.) In fact, one in 60 female nonidentical twins gives birth to multiples.