Have you heard about this device?
http://www.odondevice.org/
This could be an interesting device for obstetrics:
http://www.youtube.com/watch?v=fFEFkAnL93A&feature=youtu.be
It is currently being endorsed by WHO who want to study it in ressource poor settings.
http://www.who.int/reproductivehealth/topics/maternal_perinatal/odon_device/en/