 Tarnier's idea was to "split" mechanically the grabbing of the fetal head (between the forceps blades) on which the operator does not intervene after their correct positioning, from a mechanical accessory set on the forceps itself, the "tractor" on which the operator exercises traction needed to pull down the fetal head in the correct axis of the pelvic excavation.Tarnier forceps (and its multiple derivatives under other names) remained the most widely used system in the world until the development of the cesarean section.Forceps had a profound influence on obstetrics as it allowed for the speedy delivery of the baby in cases of difficult or obstructed labour.