There was an article on here the other day about women with PCOS being late bloomers fertility wise. That was definitely true for my mom. She needed fertility drugs to conceive my sister and I in her early twenties, she got accidentally pregnant with my now 12 year old brother when she thought she was not ovulating in her late 30's and had one of her easiest pregnancies.
But, only you can decide what chances you are willing to take. Personally, I'm 25 and TTC #1 now, partly because we feel we're ready to be parents and want kids, partly because I'm afraid of what waiting could do to my fertility (even with that study and my mother's history), and partly because we don't particularly want to be older parents. We always talked about having our kids while we are still fairly young. But, if I weren't TTC now, I would seriously consider harvesting eggs or at least looking into it. My mother's sisters have had very bad luck with their fertility. | 
Egg Harvesting 
