About This Page
This is a clinician-written, evidence-based summary aligned to the 2026 MLA Content Map. It is intended for medical students and junior doctors preparing for the UKMLA. Always cross-reference with NICE guidance, local protocols, and clinical judgement.
The Bottom Line
- Stage 1: onset of regular contractions to full cervical dilatation (10 cm). Latent phase <4 cm. Active phase 4–10 cm
- Stage 2: full dilatation to delivery of baby. Passive (descent) and active (pushing) phases
- Stage 3: delivery of placenta and membranes. Active management (oxytocin 10 IU IM) recommended
- Expected cervical dilatation in active labour: ~0.5 cm/h (may be slower in nulliparous)
- Pain relief options: Entonox, pethidine/diamorphine, epidural, water birth, TENS
- Partogram: graphical record of progress — plots cervical dilatation, descent, contractions, maternal/fetal obs
Overview
Normal labour is defined as the spontaneous onset of regular uterine contractions leading to progressive cervical dilatation and effacement, descent of the presenting part, and delivery of the baby and placenta. Labour is divided into three stages. The first stage covers the onset of regular contractions to full cervical dilatation (10 cm). The second stage is from full dilatation to delivery of the baby. The third stage is delivery of the placenta and membranes. In the UK, NICE NG235 (Intrapartum care) provides comprehensive guidance on care during labour for healthy women with uncomplicated pregnancies.
Epidemiology
Approximately 640,000 women give birth annually in England and Wales. The spontaneous vaginal delivery rate is approximately 52–55%. The overall caesarean section rate is approximately 30–35% (with significant variation between units), and the instrumental delivery rate is approximately 10–12%. Median duration of first labours is approximately 8 hours (rarely exceeds 18 hours); subsequent labours are typically shorter. Place of birth options include obstetric unit, alongside midwifery unit, freestanding midwifery unit, and home birth.
Clinical Features
Symptoms
Regular, progressively intensifying uterine contractions
"Show" — mucoid blood-stained vaginal discharge (cervical plug)
Spontaneous rupture of membranes ("waters breaking")
Lower back pain and pelvic pressure
Urge to push or bear down (second stage)
Meconium-stained liquor
Continuous abdominal pain between contractions
Signs
Cervical dilatation and effacement on vaginal examination
Uterine contractions: ≥3 in 10 minutes, each lasting >40 seconds
Descent of the presenting part (assessed by fifths palpable abdominally and station vaginally)
Normal fetal heart rate pattern on intermittent auscultation or CTG (110–160 bpm)
Abnormal CTG patterns (late decelerations, absent variability, bradycardia)
Investigations
First-line
Vaginal examinationAssess cervical dilatation, effacement, station, position, and presentation. Performed every 4 hours in first stage
Intermittent auscultationFetal heart rate auscultation with Pinard stethoscope or Doppler every 15 min in 1st stage, every 5 min in 2nd stage (low-risk)
PartogramGraphical record: cervical dilatation, descent, contractions, maternal observations (BP, pulse, temp, urine output), fetal heart rate, liquor colour
Second-line
Continuous CTGIf risk factors present: meconium, abnormal auscultation, oxytocin augmentation, epidural, APH, maternal pyrexia
Fetal blood sampling (FBS)If CTG pathological: pH >7.25 = reassuring, 7.20–7.25 = borderline (repeat), <7.20 = deliver
Specialist
Lactate on FBSAlternative to pH: <4.1 mmol/L = normal, 4.1–4.8 = borderline, >4.8 = abnormal
Management
NICE NG235 (Intrapartum care), 20231
First stage — latent phase
- Latent phase: irregular contractions, cervix dilating from 0 to 4 cm
- Encourage mobilisation, hydration, and relaxation at home if possible
- Offer TENS, warm bath, breathing techniques
- Admit to birth setting when in established labour (regular contractions, cervix ≥4 cm)
2
First stage — active phase
- Active phase: regular contractions, cervix dilating from 4 to 10 cm
- Expected progress: approximately 0.5 cm/h (NICE NG235). Delay if <2 cm in 4 hours
- Vaginal examination every 4 hours to assess progress
- If delay in 1st stage: offer amniotomy if membranes intact. If already ruptured, consider oxytocin augmentation
- Pain relief: Entonox (50% N₂O/50% O₂), IM pethidine 100 mg or diamorphine 5–10 mg, epidural (regional anaesthesia), water immersion
3
Second stage
- Passive phase: full dilatation but no urge to push (allow descent for up to 2 hours)
- Active phase: active maternal pushing
- Duration: up to 3 h in nulliparous (with epidural), 2 h in multiparous
- Delayed second stage: consider oxytocin augmentation, change of position, or instrumental delivery
- Continuous fetal monitoring during active pushing
4
Third stage
- Active management recommended: IM oxytocin 10 IU with delivery of anterior shoulder
- Controlled cord traction to deliver placenta
- Delayed cord clamping (≥1 min) unless indication for early clamping
- Physiological management (no oxytocin): acceptable if woman chooses — longer but higher PPH risk
- If placenta not delivered within 30 min (active) or 60 min (physiological): manual removal under anaesthesia
Complications
- Failure to progress: Delay in first or second stage — may require augmentation, instrumental delivery, or CS
- Fetal distress: Abnormal CTG — may require FBS and/or emergency delivery
- Postpartum haemorrhage: Reduced by active management of 3rd stage
- Perineal trauma: 1st to 4th degree tears — 3rd/4th degree (OASIS) require surgical repair
- Retained placenta: Placenta not delivered within 30–60 min — manual removal needed
- Shoulder dystocia: Head delivered but shoulders impacted — obstetric emergency
UKMLA Exam Tips
- 1Established labour = regular contractions + cervix ≥4 cm with progressive dilatation
- 2Expected dilatation rate: ~0.5 cm/h. Delay = <2 cm in 4 hours → amniotomy ± oxytocin
- 3Active management of 3rd stage = oxytocin 10 IU IM → reduces PPH by 60%
- 4FBS pH <7.20 = deliver immediately. 7.20–7.25 = repeat in 30 min
- 5Partogram is the essential tool for monitoring labour progress
- 6Pain relief ladder: TENS → Entonox → opioids (pethidine/diamorphine) → epidural
- 7Continuous CTG required if: meconium, oxytocin, epidural, APH, maternal fever, or abnormal auscultation
practicetest your knowledge on normal labour and deliveryApply what you've learnt with UKMLA-style questions from the iatroX Q-Bank — obstetrics and beyond.
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