Eggs in an Ancestral Basket

From Taking Charge of Your Fertility:

Do you realize that a part of every single one of us resided inside our maternal grandmother’s uterus, even before our own mothers were born? Unlike male fetuses which contain no sperm, female fetuses already contain all the eggs that the newborn child will ever have. What that means, practically speaking, is that when your mother was just a fetus inside hermother, she already had developed one of the eggs that eventually became you.

Wow.