per vaginam

Etymology
Naturalized into medical English from neoclassical use of in the professions. Exists in loanword form (retaining the Latin inflection, -am) and also in a further naturalized form with reanalysis in English morphology, =  +, in parallel with other per + [English noun] constructions, such as per instructions or per statute.

Adverb

 * 1)  Through the vagina, as  by the vaginal route of administration.