meredith. i am preg with baby no 4. i had 3 natural, all no probs then after DH had vas i wanted more.
we did IVF/ ICSI. 2 x full stim cycles. 6 BFN's and finally a BFP.
i felt a little like you, thinking some women don't even have one and i am wanting 4 ?
but the thing is the feeling didn't go away and it took 3 years for me to get my BFP.

good luck to you. whatever you decide. x o