Vagina isn't a dirty word, you can say it, but yeah Mid-wife probably works better...  Or "Ooba Droid" is my preferred name since for some weird ass reason it says that...  "Oooba...  oooooba..."

Official name in StarWars.com databank is Midwife Droid, though---http://www.starwars.com/databank/droid/midwifedroid/ According to the databank, the Polis Massans pulled these droids out of storage, not having anything readily available to them that was acquainted with humanoid physiologies. The "ooba, ooba" was supposed to be a soothing sound, audible to humans. (I guess Polis Massan communication is not otherwise audible to humans.)