Despite HEXAL, I wouldn't use "native preparation" for a microscopic preparation.

"nativ" in this sense means natural/untreated, so depending on the context, either "unstained" or even "fresh" preparation ...

HTH

This is the usual term.

Pschyrembel klinisches Wörterbuch 257. Auflage:
"Nativpräparat n.: engl. native preparation; natiürlich, nicht gefärbtes od. fixiertes mikroskop. Präparat."

Ich arbeite gerade an einer ÜS und werde die ÜS aus dem Pschyrembel nehmen.

> Despite HEXAL and Psychrembel, I wouldn't ALWAYS use "native preparation" for a microscopic preparation.

It really does depend on context.

Of course, there are occasions when "native preparation/specimen" are used - usually in the lab, so probably for Prithi in a specialised context "native specimen/preparation" would be fine.

However, if you do a Google search
"Nativpräparat" -10,500 hits
"native preparation" - 898
"native specimen" - 609
including hits like "Oaks or native specimen trees that are removed or killed as a result of ..."

Considering that there are far more English than German sources out there, doesn't this tell you something about the relative frequency of use?

Take, for example (grabbed quickly from wiki):
"Kolpitis"
"Deshalb sollte bei der gynäkologischen Routineuntersuchung regelmäßig der PH-Wert gemessen und ein mikrobiologisches Nativpräparat angelegt werden, um eine Entzündung frühzeitig zu erkennen."
http://de.wikipedia.org/wiki/Kolpitis
The equivalent wiki version in English doesn't mention "native" anything.

Try looking for "vaginitis" (or would you rather translate this as "colpitis"? ;-) and "native preparation" - 24 hits, mostly from non-native English sources (German, Russian ...).

In this case, it would be better to translate as "(fresh vaginal) smear" or "fresh wet mount" or "fresh specimen" than as "native preparation/specimen"

All I am trying to say is that the literal translation may not always be the best.

@Sybill (AE)
A word of warning - Pschyrembel is not perfect: there are some odd English offerings in it.

native????

surely doesn't fit, I ahve worked ina few medical labs doing blood testing and it is usually a fresh specimen.