Assisted vaginal birth — Rapid | Doctor’s Passport

Synopsis

Assess when forceps or vacuum assistance may provide a safe route to birth, explain the alternatives, and recognise prerequisites, stopping points and postnatal complications.

Assisted vaginal birth may be appropriate for fetal concern, prolonged second stage, maternal need to limit pushing or a request for assistance.
The cervix must be fully dilated, membranes ruptured and the head engaged, with presentation, position and station established.
Adequate analgesia, consent, an emptied bladder, a competent operator and a realistic backup plan are essential.
The instrument and setting depend on urgency, fetal position and station, gestation and the operator's expertise.
Rotational forceps require experienced practice or direct supervision; ultrasound confirmation of position is advisable for Kielland's rotational forceps.
A successful low assisted birth can avoid the difficulties of a second-stage caesarean, but a prolonged unsuccessful attempt adds risk.
After forceps or ventouse birth, offer a single intravenous prophylactic antibiotic dose within six hours of cord clamping.

Key red flags

No progressive descent with correctly applied moderate traction requires abandonment or expert reassessment.

Two vacuum cup detachments require vacuum-assisted birth to be discontinued.

Forceps that do not apply or approximate easily, or rotation that requires more than gentle pressure, must not be forced.

A deteriorating fetal heart pattern requires an updated urgent birth decision, including whether the proposed vaginal attempt remains achievable.

Increasing neonatal scalp swelling, pallor, tachycardia or poor perfusion after vacuum birth requires urgent assessment for significant bleeding.

Investigation priorities

Abdominal and vaginal assessmentFirst step

Establish whether the anatomical conditions permit a safe attempt.

Management branches

Before assistanceAgree a feasible birth plan

A maternal or fetal indication for assistance has been identified during second stage.

Explain why assistance is advised and discuss the proposed instrument, expected benefit, trauma risks, possible failure and feasible alternatives.
Confirm the prerequisites and document position and station, with ultrasound when uncertainty or rotational planning makes it useful.
Ensure a suitably experienced operator, adequate analgesia, an emptied bladder and access to appropriate assistance and resuscitation.
Choose the location according to anticipated difficulty, including theatre when an immediate caesarean may be needed, and state the stopping and backup plan.

Key medicines

Co-amoxiclav after assisted vaginal birthUse a single intravenous dose of co-amoxiclav 1.2 g, containing amoxicillin 1 g and clavulanic acid 200 mg, as soon as practicable and within six hours after cord clamping when suitable. This is the regimen studied in the UK ANODE trial supporting prophylaxis.Check penicillin allergy, previous co-amoxiclav-associated liver injury and concurrent treatment. NICE permits a locally agreed alternative for allergy; established sepsis or major contaminated trauma requires its own treatment assessment rather than prophylaxis alone.

Analgesia and anaesthesia for assistanceThe anaesthetist or trained operator selects an epidural top-up, spinal technique, pudendal block or local infiltration according to the procedure and existing analgesia. Drug, concentration and volume depend on the block already present, patient factors and anticipated manipulation.Do not proceed through pain because an instrument has already been selected. Rotational or potentially difficult procedures generally require more substantial anaesthesia, and all additional local anaesthetic doses must account for cumulative exposure.

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