A female can be a 68W though as was stated they can not be with a combat arms unit (i.e. infantry, field artillery, cav, etc) what you are looking for if you were to go army would be a 68W with the F1 ASI (additional skill identifier) they are specifically flight medics. It is possible to be on a medevac bird without having a F1 but it's rare. On a similar note if you do plan on going into the Army as a flight medic be prepared to be a crew chief 90% of the time and a medic 10% of the time, as all flight medics are crew chiefs as well. In other words you are responsible for the maintaining the bird as well as personnel who will no doubt be hitching a ride.
The reasoning why military medics are only certified as basics fresh out of training is simply due to class room hours that the NREMT requires in reality military medics *are supposed* to be trained somewhere in between an intermediate and a paramedic. i say supposed t, because different services teach things differently and hell different instructors will teach things differently so sometimes you end up with real high speed medics right outta training and some you would trust a CLS person before them.
Now I am biased but I would recommend the Army if you want to get a foothold in the civilian flight medic world. As you can specifically requst that you have the F1 school put in your enlistment contract and if you have that ASI you will more likely than not be working with dustoff as they never have enough flight medics.
On a side note, if what i heard on the grapevine is true a army medic and naval FMF Corpsman can challenge the NREMT-P exam after a year combat experience if that is entirely true I am not sure, like I said just a rumor floating around, and if it is true you may want to study your *** off for a few months before even thinking of challenging.