What is the step-by-step procedure for performing a forceps delivery?

Step-by-Step Procedure for Forceps Delivery

Forceps delivery requires meticulous pre-procedure assessment, precise instrument application, controlled traction with maternal effort, and careful post-delivery evaluation—performed only by operators with demonstrated competency or under direct supervision of experienced obstetricians. 1

Pre-Procedure Assessment and Preparation

Clinical Prerequisites (Must All Be Met)

• Cervix must be fully dilated (forceps are absolutely contraindicated before complete dilation) 1
• Membranes ruptured
• Fetal head engaged in pelvis
• Position of fetal head accurately determined (station, position, flexion)
• Pelvis assessed as adequate for vaginal delivery
• Bladder emptied (catheterize if necessary)

Determine Classification and Location

Classify the delivery based on station and rotation required:

• Low-pelvic, non-rotational: Can be performed in birth room 1
• Midpelvic or rotational: Must be performed in operating theatre with immediate access to caesarean section 1

Consent and Team Assembly

• Verbal consent for low-pelvic procedures (document in notes)
• Written consent for trial of forceps in theatre 1
• Ensure experienced operator present for all midpelvic/rotational attempts 1
• Notify neonatology team, especially for complex cases
• Ensure adequate analgesia (regional or pudendal block)

Instrument Selection

Choose forceps type based on fetal position and operator expertise:

• Direct traction forceps (e.g., Simpson, Neville-Barnes): For occipito-anterior positions at low station
• Kielland's rotational forceps: For malposition requiring rotation (requires specific expertise) 1
• Alternative approach: Manual rotation followed by direct traction forceps 1

Note: Kielland's forceps have lower failure rates (RR 0.32) and less neonatal trauma (RR 0.62) compared to rotational vacuum, but require experienced operators 1

Application Technique

Step 1: Position and Draping

• Position woman in lithotomy with adequate hip flexion
• Ensure sterile technique
• Operator should adopt appropriate posture to allow controlled traction along pelvic curve

Step 2: Blade Application

• Identify fetal position precisely before application
• Apply blades sequentially (typically left blade first, then right)
• Blades should be positioned along sides of fetal head (biparietal application)
• Avoid maternal soft tissue entrapment
• Check application before locking:
  • Sagittal suture equidistant from both blades
  • Posterior fontanelle one fingerbreadth above plane of shanks
  • No more than one fingertip should fit between blade and fetal head

Step 3: Verify Correct Application

Perform systematic check:

• Blades symmetric and appropriately positioned
• Handles lock easily without force
• Fenestration admits only fingertip amount of fetal scalp
• No maternal tissue trapped

Traction and Delivery

Traction Principles

• Apply traction only during contractions with maternal pushing effort
• Direction of pull follows pelvic curve (initially downward and outward, then upward as head crowns)
• Use moderate, steady traction—never jerking or excessive force
• Operator should be prepared to stop if no descent occurs

For Rotational Forceps (Kielland's)

• Rotation performed before traction
• Rotate slowly and deliberately to occipito-anterior position
• Then proceed with traction as above

Episiotomy Consideration

• Episiotomy rate with forceps exceeds 90% 1
• Perform mediolateral episiotomy when head distends perineum if tissue appears tight
• Timing: As head crowns and perineum blanches

Delivery Completion

• As head delivers, extend handles upward following pelvic curve
• Remove forceps after head delivers (between contractions if possible)
• Deliver shoulders and body with standard maneuvers

Discontinuation Criteria (When to Stop)

Abandon the procedure if:

• No progressive descent with moderate traction after 2-3 pulls 1
• Suspected cephalopelvic disproportion
• Incorrect position diagnosis suspected
• Application cannot be achieved correctly
• Maximum attempt parameters: Delivery should be completed or abandoned within reasonable timeframe

Less experienced operators should seek senior support immediately if minimal descent with first two pulls 1

Post-Delivery Management

Immediate Maternal Care

• Careful inspection for trauma:
  • Expect high episiotomy rate (≥90%) 1
  • OASI risk 8-12% with forceps 1
  • Check for cervical, vaginal, and perineal lacerations
• Repair any injuries systematically
• Monitor for postpartum hemorrhage (risk 10-40%) 1

Neonatal Assessment

• Notify neonatology of forceps delivery, especially if:
  • Sequential instruments used (intracranial hemorrhage risk 1 in 256) 1
  • Difficult or prolonged procedure
  • Preterm infant (avoid forceps <32 weeks; use caution 32-36 weeks) 1
• Examine for:
  • Facial nerve palsy (rare but specific to forceps) 1
  • Skull fracture (rare, mainly forceps) 1
  • Facial/scalp lacerations (10% incidence) 1
  • Signs of intracranial hemorrhage (5-15 per 10,000) 1

Documentation

Document thoroughly:

• Indication for procedure
• Classification (station, position, rotation)
• Instrument used
• Number of pulls and ease of delivery
• Complications encountered
• Neonatal condition at birth
• Consent obtained

Critical Safety Points

Absolute contraindications:

• Cervix not fully dilated 1
• Face presentation 1
• Unengaged head

Relative contraindications requiring senior involvement:

• Fetal bleeding disorders (e.g., alloimmune thrombocytopenia) 1
• Osteogenesis imperfecta 1
• Gestational age <32 weeks 1

Avoid sequential instruments (vacuum followed by forceps) whenever possible—this dramatically increases intracranial hemorrhage risk from 1 in 860-954 to 1 in 256 1

Operator competency is paramount: Complex deliveries (midpelvic, rotational) should only be performed by experienced operators or under direct supervision 1