I believe you meant to ask, is it possible that this is why she is impure for fourteen days instead of seven (as the sixty six days are days when her blood is considered pure , not impure).

While I have not seen this exact answer, there are explanations on the Pasuk in Tazria (12:5) that explain why impurity gravitates towards women more frequently than men. [For example, see the Kitzur Alshich on the Pasuk above.] This includes, in part, a baby girl drawing impurity more than a baby boy, and the fact that a baby girl can indeed become a Nidah.

All the best,

Yaakov Montrose