The obstetric forceps--are we using the appropriate tools?

A total of 166 pairs of obstetric forceps of three different types in regular use in two major obstetric units was measured and compared with manufacturers' master instruments and drawings. As well as linear measurements of blade, shank and handle the distances between the tips and maximum distance between the blades, and the mean radius of the cephalic curve were determined. The purpose of the study was to assess the suitability of instruments in common use for present day practice. It was found that the measurements differed significantly from the original descriptions and there were wide variations between instruments of the same type, even when supplied by the same manufacturer. In some cases the blades had not been packed in matching pairs in the Central Sterile Supplies Department. It is suggested that critical reappraisal of the forceps in current use in many obstetric units is overdue. As well as a need for reconsidering the type of forceps used the dimensions of individual pairs should be checked.