Induction of labour

Red Flags

Uterine hyperstimulation with non-reassuring CTG during prostaglandin or oxytocin — stop agent, remove pessary if present, lateral position, IV fluids; tocolysis (terbutaline) if persistent; deliver if not resolving^[1]
Suspected uterine rupture during induction with prior caesarean — emergency theatre; high index of suspicion with VBAC^[1]
Cord prolapse on artificial membrane rupture — emergency caesarean; manual elevation of presenting part; knee-chest position^[1]
Failed induction (cervix unfavourable after maximum prostaglandin and 12–24 h of oxytocin in active labour) — caesarean section per local protocol^[1]

First-line treatment

Interventions

Membrane sweep at 39–41 weeks^[1]
Offer at term to women undergoing or considering induction; reduces need for formal induction; consent required as part of clinic visit
Cervical ripening for unfavourable cervix (Bishop ≤6)^[1]
Mechanical (Foley balloon, double-balloon catheter) or pharmacological (vaginal PGE2 pessary or gel; oral or vaginal misoprostol per local protocol). Mechanical preferred in VBAC and some cardiac/asthmatic women
Active labour induction^[1]
Artificial rupture of membranes followed by oxytocin titration once Bishop favourable; continuous CTG; titrate oxytocin to 3–4 contractions in 10 minutes; manage hyperstimulation per protocol
Alternative — outpatient cervical ripening^[1]
Selected low-risk women with mechanical ripening (Foley) or low-dose vaginal PGE2 in pathways with safe community follow-up
Mechanical cervical ripening (Foley or double-balloon)^[1]
Insert under aseptic technique; inflate to 30–60 mL; remove at 12 h or spontaneous expulsion; safe in VBAC and many cardiac and asthmatic women; very low hyperstimulation risk

First-line drug therapy

Drug	Class	Adult	Paediatric	Notes
Vaginal dinoprostone (PGE2) pessary or gel^[1]	Synthetic prostaglandin E2	Pessary 10 mg controlled-release × 24 h; gel 1–2 mg, repeat at 6 h if no response	—	Primary cervical ripening; remove for hyperstimulation, established labour, ROM, or 30 min before oxytocin start; avoid with prior caesarean (uterine rupture risk)
Misoprostol (vaginal or oral)^[1]	Synthetic prostaglandin E1	Vaginal: 25 µg every 4 h × max 5 doses. Oral: 50 µg every 4 h. Sublingual 25 µg every 2 h (per local protocol)	—	Cervical ripening and labour induction; lower cost than PGE2; contraindicated with prior caesarean section (rupture risk); follow weight-based titration
Oxytocin (IV infusion)^[1]	Synthetic oxytocin	Start 1–4 mU/min IV infusion; double every 30 min to maximum 32 mU/min titrated to 3–4 contractions in 10 min	—	After cervical ripening or with favourable cervix; continuous CTG; manage hyperstimulation by reducing rate; do not co-administer with prostaglandin within 30 min

Vaginal dinoprostone (PGE2) pessary or gel^[1]

Synthetic prostaglandin E2

Adult: Pessary 10 mg controlled-release × 24 h; gel 1–2 mg, repeat at 6 h if no response
Paediatric: —

Primary cervical ripening; remove for hyperstimulation, established labour, ROM, or 30 min before oxytocin start; avoid with prior caesarean (uterine rupture risk)

Misoprostol (vaginal or oral)^[1]

Synthetic prostaglandin E1

Adult: Vaginal: 25 µg every 4 h × max 5 doses. Oral: 50 µg every 4 h. Sublingual 25 µg every 2 h (per local protocol)
Paediatric: —

Cervical ripening and labour induction; lower cost than PGE2; contraindicated with prior caesarean section (rupture risk); follow weight-based titration

Oxytocin (IV infusion)^[1]

Synthetic oxytocin

Adult: Start 1–4 mU/min IV infusion; double every 30 min to maximum 32 mU/min titrated to 3–4 contractions in 10 min
Paediatric: —

After cervical ripening or with favourable cervix; continuous CTG; manage hyperstimulation by reducing rate; do not co-administer with prostaglandin within 30 min

Safety-net

Induction can take 24–48 hours from start of cervical ripening to delivery — anticipate longer first labour and bring support, food, drinks per local policy^[1]
Persistent abdominal pain between contractions, frank bleeding, or change in fetal movements — tell the midwifery team immediately^[1]
If induction fails or fetal distress occurs, caesarean is the safest course — counselling about this possibility is part of pre-induction consent^[1]

Referral criteria

Indications for induction at unfavourable term (post-dates 41+, hypertension, diabetes, FGR, IUFD, PROM)Obstetric labour ward booking^[1]
Prior caesarean section requesting trial of labourSenior obstetric review and counselling; mechanical ripening preferred^[1]
Failed induction or non-reassuring CTG during inductionTheatre and obstetric escalation^[1]
Cervical ripening or induction in cardiac, severe asthma, or severe anaemia patientsJoint obstetric and medical anaesthetic team^[1]

Clinical summary

Indications, methods, and monitoring for elective and indicated induction of labour at term and post-dates in singleton pregnancies.

References

1.FOGSI-ICOG Good Clinical Practice Recommendations on Induction of Labour (2019, refreshed); WHO recommendations on induction of labour at or beyond term (2022); NICE NG207 (2022)