If there were to be female voices, they'd need to be totally redone.  At the moment, there is currently a full female V.O set in the mod, it's just not used anywhere.  My guess is they were intended for the rebel medic who uses a female model on the majority of maps, however it wasn't used because (compared to the others) the V.O is pretty low quality.  The recordings are good in their own right, but there isn't really the same.... feeling in her voice compared to any of the male Voiceovers.  They don't sound as atmospheric or natural as the male voices.

If you want to listen to the female Voiceovers, they are located in the mod at the following location:
Bf2142 Install Folder/mods/firststrike/sound_client.zip/vo/rebel/fem_trooper/local/
You'll need to install something like audacity or VLC player to listen to them.  I recomend Audacity as most players (including VLC) seem to cut off about 0.25 of a second at the end of the sound file.  That's not usually noticeable, but these sound clips are very short and sometimes you don't hear it all.

Ok.. nothing to see here.  Move along... Move along...