Unintended pregnancy ratio at conception
Definition
The unintended pregnancy ratio at conception is the number of unintended pregnancies for every 1000 pregnancies (both counts measured at the time of conception). Since many conceptions go undetected because they are destroyed before the prospective mother is even aware of them, the measure in practice might prefer to the ratio for detected pregnancies.
This number has been crudely estimated but not properly measured.
See also the unintended pregnancy ratio at birth.