Prenatal Vitamins

What does everyone think about them? Do you think it helps with fertility? I was told I had a slim chance of ever having kids by my doctor, and he told me that prenatals wouldn't help my case any. The thing is, is ever since I've been taking them, this is the most fertile I've ever been. Do you guys think prenatals really do help with fertility? If so, maybe I should find myself a new doctor.