Someone once told me that prenatal vitamins make women more fertile, is this just a crazy myth?

No but healthy: The prenatal vitamins make you more healthy or add some nutrients to your system but it does not have any fertility drugs in the vitamins. It is good to take these when you are pregnant as they give you the combination of vitamins and minerals that are good for a pregnancy. They do help your body function more efficiently. I hope this helped.

Proven to help fert.: Vitamin and mineral deficiencies are common; over 90% of Americans are deficient, most in multiple essential nutrients. Deficiencies of Vit. C, Folic Acid, Iron and other nutrients can reduce fertility. Multivitamins (and prenatals are a multivit.) are proven to improve fertility. But it won't help those who aren't deficient. See http://tinyurl.com/7pjgjz and http://tinyurl.com/mzrkbx8