Abstract: An obstetric vacuum extractor (20) comprises a cylinder (22) communicating with a cup (26), and a handle (46) connected to a piston (38) via an extensible bias element (52) to evacuate the cup. The bias element permits relative movement between the handle and the piston. The bias element limits force transmitted to the piston, and movement of the piston relative to the handle operates an indicator to confirm that low pressure has been maintained within the cup. A cup for such an extractor comprises inner (130) and outer (132) sections, at least the outer section being reconfigurable, by applying distal force to a proximal side of the cup, from a convex insertion state for insertion into a mother's birth canal into a concave engagement state for engagement with a baby's head. A boundary between the sections is shaped such that the inner section may be concave while the outer section is convex, to create an inner suction cup.