IMPORTANT INSTRUMENTS. OBSTRETIC FORCEPS Definition: Obstetric forceps are specially designed instruments which are helpful for delivery of the head and delivery of the fetus through this instrument. Varieties of -obstetric forceps: Three forceps are used in obstetric practice. acronym of forceps F – Favorable head position and stationO – Open orificeR – rupture membraneC – Contraction presentE – Engage headP – Pelvi Materi –(Major Cephalopelvic Dis Proportion)S – Lithotomy Position