Should you italicize Latin phrases like in vitro, in vivo, etc.?

Scientific writing often uses a few Latin phrases, either abbreviated (etc. for et cetera and et al. for et alii) or spelt out (in vitro, in vivo, in situ). Should they be set in italics? As is common with such queries, there is no single right or wrong answer, although, increasingly, the trend is to dispense with italics.

Should Latin phrases be italicized in scientific writing?

Most publishers and style guides instruct authors not to use italics for such phrases. Both Springer and Elsevier, for example, insist on setting “in vitro,” “in vivo,” and “in situ” in normal, or Roman, font, and so does the Chicago Manual of Style and Scientific Style and Format. The Oxford Dictionary for Scientific Writers and Editors, however, insists that in vivo and in vitro should be set in italics.

The only sensible advice in this matter is, therefore, to follow your target journal’s practice. And if the target journal doesn’t specify this in their author guidelines, you can look at a few recently published articles and follow their style. 

Another issue many authors are unclear about is Using “et al.” in research papers for in-text references.