Yes, they do.
Well they use computers to make the voices sound squeaky.
The cast of VoiceS - 2010 includes: Helena Arenbergerova
The cast of Voices - 1985 includes: Joanna Priestley
Jaden actors does
In Shakespeare's time the women's parts were played by boys whose voices had not yet broken. When their voices broke, they could move on to men's roles. Actors were not surgically encouraged to have high voices as singers in some parts of Europe were. Nor did they use falsetto voices except for comedy parts like the nurse (and possibly the witches in Macbeth)
The cast of Voices - 2008 includes: Alastair Clayton as Unnamed
The cast of Carrying Voices - 2005 includes: Cheryl McCloud
The cast of Silenced Voices - 2010 includes: Gustavo Teran
The cast of Voices of Sculpture - 2010 includes: Scott Bryce
The cast of Voices - 2005 includes: Lance Arthur Smith as Saul
The cast of Restrospective Voices - 2008 includes: Sandra Roque
The cast of Cardboard Voices - 2010 includes: Katherine Pottinger