Management of First Stage of Labour (DC Datta - Concise Framework)

Definition

Phases of First Stage

• Active phase starts at 3-4 cm (Friedman's classical view); contemporary data (Zhang et al.) suggests transition may occur at 5-6 cm
• Minimum rate of dilation in active phase: 1.2 cm/hr (nullipara), 1.5 cm/hr (multipara) - Friedman's criteria
• The Friedman curve is a sigmoid (S-shaped) curve plotting cervical dilatation against time

Management on Admission

History

• Time of onset and frequency of uterine contractions
• Show (blood-stained mucus discharge)
• Leaking per vaginum (to rule out PROM)
• Fetal movements
• Obstetric history: parity, previous deliveries, complications
• Medical comorbidities

Examination on Admission

1. General examination: pulse, BP, temperature, pallor, oedema
2. Abdominal examination:
   • Fundal height (gestational age)
   • Lie, presentation, position (Leopold's manoeuvres)
   • Engagement of presenting part
   • Frequency and duration of contractions
   • FHS - fetal heart sounds
3. Vaginal examination (P/V):
   • Cervical dilatation (cm)
   • Cervical effacement (%)
   • Cervical consistency (firm / soft) and position (posterior / anterior)
   • Station of presenting part (relation to ischial spines: -3 to +3)
   • Membranes - intact or ruptured
   • Pelvis assessment

Investigations

• Urine: albumin, sugar, ketones
• Haemoglobin
• Blood group and Rh typing
• If indicated: HBsAg, HIV, VDRL

General Care During First Stage

Psychological Support

• Reassure and encourage the woman
• Allow a birth companion/partner (evidence supports reduced labour duration and analgesia requirement)
• Explain each procedure

Ambulation and Position

• Ambulatory labour is encouraged in the latent phase (reduces duration, improves progress)
• Lateral (left lateral decubitus) position preferred when recumbent - prevents supine hypotension syndrome
• Upright position shortens first stage

Oral Intake

• Traditionally restricted (risk of Mendelson's syndrome - aspiration of acid gastric contents under GA)
• Small quantities of clear fluids may be allowed; solid food generally avoided
• IV line should be established; IV fluids (Ringer's lactate/dextrose saline) given if prolonged labour or risk of dehydration

Bladder Care

• Encourage micturition every 2 hours
• Full bladder impedes progress; catheterise if patient cannot void

Bowel Care

• Enema is no longer routinely recommended (evidence does not support routine enema)
• A rectal evacuation may be given if requested

Perineal Preparation

• Routine perineal shaving is NOT recommended (WHO, Cochrane)

Monitoring During First Stage

Maternal Monitoring

Fetal Monitoring

• Normal FHR: 110-160 beats/min
• Decelerations, especially late decelerations, indicate fetal distress

Vaginal Examination

• Every 4 hours routinely during active phase to assess progress
• Document: cervical dilatation, station, position, membranes

The Partograph (Partogram)

What It Records

• Cervical dilatation plotted against time
• Descent of presenting part
• Fetal heart rate
• Uterine contractions (frequency and duration)
• Maternal vitals (pulse, BP, temperature)
• Urine (volume, protein, ketones)
• Oxytocin if used
• Drugs and IV fluids

Alert and Action Lines

• Alert line: Starts at active phase (4 cm), slopes at 1 cm/hr - if progress falls to the right of this line, patient should be transferred to a higher centre
• Action line: 4 hours to the right of the alert line - if reached, active intervention (amniotomy, oxytocin augmentation, or CS) is required
• Helps identify prolonged labour and failure to progress early

Analgesia in First Stage

• Epidural analgesia does NOT increase the CS rate (modern evidence)
• Pethidine causes neonatal respiratory depression - avoid within 4 hours of delivery; antidote = naloxone

Amniotomy (Artificial Rupture of Membranes - ARM)

Indications

• Slow progress in active phase
• To apply fetal scalp electrode for direct CTG
• Prior to oxytocin augmentation
• To detect meconium in liquor

Technique

• Done under aseptic conditions with an amniohook
• Note colour, amount, and odour of liquor
• Check FHR before and after ARM

Risks

• Cord prolapse (especially if head not engaged)
• Infection (chorioamnionitis)
• Abruptio placentae (rare)
• Fetal distress from cord compression

Oxytocin Augmentation

Indications

• Prolonged latent phase (>20 hrs nullipara, >14 hrs multipara)
• Arrest/protracted active phase
• After ARM with no progress

Regimen (Low-dose Oxford)

• Start at 1-2 mU/min, increase by 1-2 mU/min every 30-40 minutes
• Target: 3 contractions in 10 minutes, each lasting 40-60 seconds
• Maximum dose: 20-40 mU/min
• Maintain with continuous CTG

Contraindications

• Previous uterine scar (relative)
• Malpresentation
• CPD (cephalopelvic disproportion)
• Fetal distress
• Grand multipara (risk of uterine rupture)

Diagnosis of Prolonged Labour in First Stage

Causes of Prolonged Labour (3 P's)

1. Powers - uterine inertia (inadequate contractions)
2. Passenger - fetal macrosomia, malpresentation, malposition
3. Passage - bony pelvis (CPD), soft tissue dystocia

Summary of Viva Key Points

1. First stage ends at full cervical dilatation (10 cm)
2. Latent phase: up to 20 hrs (nullipara), 14 hrs (multipara)
3. Active phase begins at 3-4 cm (Friedman); modern data - 5-6 cm
4. FHR checked every 15 min in active phase
5. P/V done every 4 hours
6. Partograph - alert line at 1 cm/hr, action line 4 hours to the right
7. Routine enema and perineal shaving are NOT recommended
8. Left lateral position to avoid aortocaval compression
9. Epidural - gold standard analgesia; does not increase CS rate
10. Pethidine - do not give within 4 hours of delivery (neonatal respiratory depression)
11. ARM - check FHR immediately before and after
12. Amniotomy + oxytocin: action taken once action line is reached on partograph