This document provides an overview of normal labor, including: 1. It defines labor and the three stages of labor, and discusses mechanisms and signs of labor onset. 2. Intrapartum monitoring of both mother and fetus is described, including vital signs, fetal heart rate monitoring, and use of the partogram. 3. Management of the three stages of labor is outlined, including pain relief, monitoring, second stage delivery techniques, and third stage placental delivery.

1. Kingdom of Saudi Arabia
Ministry of Higher Education
King Faisal University
College of Medicine
Normal Labor
By/
Fahad AlHulaibi Mansour Al Omair
Ahmed Al Awwad Abdulaziz Al Barrak

2. Objectives
By end of this Tutorial, you will be able to :
 Diagnose The Onset Of Labor .
 Define Stages Of Labor.
 Understand The Mechanism Of
Normal Labor.
 Monitoring The Mother & The Fetus During
Labor.
 Understand Management Of Normal
Labor.

3. 30 months
-
24 months
=
6 months
Or
24 weeks
“age of viability”

4. Definition
 Labor:
Is the process whereby the product of conception are
expelled from uterian cavity after 24th week of
gestation.

5. Definition
 Premature labour:
labour occurring before the commencement of the 37th
week of gestation
 Prolonged labour:
labour lasting in excess of:
24 hours in a primigravida
&16 hours in a multigravida.

6. Onset of labour
 The onset of labour is defined as
the time of onset of regular, painful
uterine contractions, which produce
progressive effacement and
dilatation of the cervix.
 false labour: where the onset of
painful contractions is not
associated with progressive
dilatation of the cervix.

8.  The clinical signs of the onset of labour include:
1. The onset of regular, painful contractions that
produce progressive cervical dilatation.
2. The exhibition of a vaginal show - the passage of
blood stained mucus.
3. Rupture of the fetal membranes - may occur at the
time of onset of contractions or it may be delayed
until the delivery of the fetus.

9. Stages of labour
 The First Stage
• onset of labour
start
• Cervix reached full
end dilatation

10.  The Second Stage
• Cervix reached full
start dilatation
• expulsion of the fetus
end

11.  The Third Stage “Placenta Stage “
• delivery of the child.
start
• expulsion of placenta.
end

12.  The classic signs of placental separation :
1. show of bright blood.
2. apparent lengthening of the umbilical cord
3. elevation of the uterine fundus within the abdominal
cavity .

13. MECHANISM OF
NORMAL LABOUR

14. Mechanism of Normal labour
 Engagement of the head normally occurs before the
onset of labour in the primigravid woman but may not
occur until labour is well established in a multipara.
 Only 2/5th of the head will be palpable per
abdomen
 Zero station on vaginal examination

21. Mechanism of labour
 1. Descent of the head provides a measure of the
progress of labour
Descent occurs throughout
labour

22.  2. Flexion of the head occurs as it descends and
meets the pelvic floor, bringing the chin into contact
with the fetal thorax.
Flexion produces
a smaller diameter
of presentation
(suboccipitobregmatic
diameter)

23.  3. Internal rotation:
The head rotates as it reaches pelvic floor and the
occiput normally rotates anteriorly from the lateral
position towards the
pubic symphysis

24.  4. Extension: The acutely flexed head descends to
distend the pelvic floor and the vulva, and the base
of the occiput comes into contact with the inferior
rami of the pubis.
The head now extends until
it is delivered. Maximal
distension of the perineum
and introitus accompanies
the final expulsion of the
head, a process that is
known as crowning.

25.  5. Restitution:
Following delivery of the head, it rotates back to be
in line with its normal relationship to the fetal
shoulders
 6. External rotation: When the
shoulders reach the pelvic floor,
they rotate into the
anteroposterior diameter of the
pelvis. This is accompanied by
rotation of the fetal head so that
the face looks laterally at the
maternal thigh.

26.  7. Delivery of the shoulders: The anterior shoulder
is delivered first by traction posteriorly on the fetal
head so that the shoulder emerges under the pubic
arch.
The posterior shoulder is
delivered by lifting the head
anteriorly over the perineum.
This is followed by rapid
delivery of the remainder of
the trunk and the lower limbs

28. INTRAPARTUM
MONITORING

29. What to monitor?
 Mother
 Temperature
 Pulse rate
 Blood pressure
 Urine

30.  Fetus
 Auscultation
 Fetal CTG
 Fetal ECG
 Scalp stimulation test
 Acid-Base balance
 Others
 Partogram

31. Mother Intrapartum monitoring
 Temperature
 Normal Temperature
 36.2°-37.2°
 Frequency
 Every 4 hours
 Pyrexia; Causes
 Infection
 Maternal exhaustion: Dehydration cause pyrexia.
 Risks
 Mother
 fetus

32. Cont.
 Pulse Rate
 Normal Range
 70-100 beats per min
 Frequency
 Hourly

33.  Blood Pressure
 Normal Range
 100/60 mm Hg to 140/90 mm Hg
 Frequency
 hourly

34.  Urine
 Items
 Volume
 Protein
 Ketones
 Frequency
 Every 2 hours

35. Fetal Monitoring
 Auscultation
 Fetal CTG
 Fetal ECG
 Acid-Base balance
 Scalp stimulation test
 Others
 Vibroacousticstimulation
 Fetal oxygen saturation

36. Auscultation
 The heart rate should be recorded every 15 minutes
in the first stage and after each contraction in the
second stage, using a Pinard fetal stethoscope
 Cardiotocography is not required when the labour
is classified as low risk.
 However, there are specific indications for electronic
fetal monitoring.

37. Indications for continuous electronic
fetal monitoring
 Maternal
 Previous caesarian section
 Pre-eclampsia
 Post-term pregnancy
 Prolonged rupture of the membranes
 Induced labour
 Diabetes
 Antepartum haemorrhage Other maternal medical
diseases

38. Cont.
 Fetal
 Fetal growth restriction
 Prematurity
 Oligohydramnios
 Multiple pregnancy
 Meconium-stained liquor
 Breech presentation

39. Cardiotocogram
 Components:
 Base line fetal heart rate
 Base line variability
 Accelerations
 Decelerations
 Uterine Contractions

41. Fetal Heart Rate
 Normal Range
 110-160 beats/min
 More than 160 is tachycardia
 Less than 110 is bradycardia

42. Baseline Variability
 Normal Range
 6-25
 Increased (more than 25)
 Early Hypoxia
 Prolonged pregnancy
 Decreased (less than 6)
 Latehypoxia
 Sleep
 Vibro-acoustic stimulation

43. Accelerations
 Transient increase in heart rate more than or equal
to 15 beats for more 15 seconds.
 Assuring of good fetal health if present

44. Decelerations
 Transient decrease in heart rate more than or equal
to 15 beats for more 15 seconds.
 Normally not present.
 Types (in relation to uterine contractions)
 Early
 Late
 Variable

45. Early Decelerations
 They are synchronous with uterine contractions.
 The nadir of the deceleration occurs at the peak of
the contraction and the decrease in heart rate is
generally less than 40 beats/min.

46. Cont.
 These decelerations are generally due to head
compression and are commonly considered to be
physiological.
 They are a common form of deceleration seen in
labour

47. Late Decelerations
 The onset of the slowing of heart rate occurs well
after the contraction is established and does not
return to the normal baseline until at least 20
seconds after the contraction is completed.
 They are indicative of fetal hypoxia.

48. Variable Decelerations
 Variable decelerations vary in timing and
amplitude, hence their name.
 An early deceleration where the heart rate falls by
more than 40 beats/min is also classified as a
variable deceleration.
 Types:
 Mild:Total duration is >30 sec, or FHR >80 bpm
 Moderate: FHR 80-70 bpm
 Severe: FHR <70 bpm for more than 1 min

49. Cont.
 The commonest cause is cord compression and the
changes may be considered to be pathological if
the cord compression is persistent

50. Uterine Contractions
 Tocodynamometer
A pressure-sensitive tocodynamometer is placed around
the maternal abdomen.
 The tocodynamometer measures only the frequency of
contractions, not their intensity or strength.
 Intrauterine pressure catheter (IUPC).
 Thismethod allows internal monitoring of contractions.
 IUPC measures both the frequency and strength of
contractions.

52. Electrocardiogram
 The fetal electrocardiogram (ECG) can be recorded
from scalp electrodes or by the placement of
maternal abdominal electrodes.

53.  Two items are important:
 Acidosis(T wave and QRS height)
 Asphyxia (PR interval and RR interval)
 The fetal ECG can also be used to identify the
nature of fetal arrhythmias.

54. Scalp stimulation test
 The examiner rubs the fetal scalp during a digital
examination.
 An acceleration is usually seen in the FHR tracing of the
uncompromised, nonacidotic fetus. The presence of an
acceleration is associated with an intact ANS and a
fetal scalp blood pH greater than 7.20.
 If an acceleration is not obtained after scalp
stimulation, fetal scalp blood can be sampled to
measure the fetal pH or one can progress to immediate
surgical delivery.

55. Fetal scalp blood sampling
 The fetal scalp is visualized through the dilated
cervix, and blood is collected in heparinized
capillary tubes
 The normal fetal capillary pH is 7.25 to 7.35 in the
first stage of labor.
A fetal scalp pH greater than or equal to 7.20 is
reassurance that the fetus is not acidotic. Labor can
proceed for 20 to 30 minutes.
 A pH of less than 7.20 may represent significant
acidosis. Delivery is thus indicated by vaginal delivery,
if possible, or cesarean delivery.

56. Others
 Vibroacoustic stimuli (VAS). Fetus is stimulated by noise
for 1 second.
 The presence of fetal accelerations in response to VAS is
considered reassuring.
 The fetus is restimulated if no accelerations occur within 10
seconds. The VAS test may be repeated up to four times.
 Normal fetal oxygen saturation: ranges between 35%
and 75%, If the fetal oxygen saturation remains above
30% during labor, fetal metabolic acidosis is excluded.

57. Partogram
 Partogram is a graphical record of key data
(maternal and fetal) during labour entered against
time on a single sheet of paper.

58. Components
 Fetal Parameters:
 FHR
 Statusof membranes or Amniotic Fluid
 Moulding
 Caput

59.  Progress of Labor:
 Cervical dilatation
 Station of head
 Uterine contractions: Frequency & Duration
 Oxytocin:
 Concentration /L
 Infusion rate
 Any other medicine & IV fluid

60.  Maternal Parameters:
 Vital data:
 Pulse
 BP
 Temparature
 Urine:
 Output
 Acetone
 Protein / Glucose

63. MANAGEMENT OF
NORMAL LABOUR

64. General principles of the management of
the first stage of labour :
• Observation and intervention if the labour becomes
abnormal by partogram .
• Pain relief during labour and emotional support for
the mother ( Narcotic agents , inhalational analgesia
and regional analgesia )
• Adequate hydration throughout labour.

65. Fetal monitoring in labour
• Fetal cardiotocography
• Basal heart rate
• Transitory changes
• The fetal electrocardiogram
• Fetal acid-base changes
• Scalp blood sampling

66. Management of the second stage
 Delivery of the head .
 Controlled descent .
 Minimizing perineal damage.
 Clamping the cord .
 Evaluation of Apgar score.

67. Evaluation of the Apgar score
0 1 2
Colour White Blue Pink
Tone Flaccid Rigid Normal
Pulse Impalpable <100 >100
beats/min beats/min
Respiration Absent Irregular Regular
Response Absent Poor Normal

68. Management of the third stage
 Recognition of placental
separation.
 Assisted delivery of the
placenta with cord traction.
 Routine use of oxytocic
agents with crowning of the
head.

69. References:
 Essential Obstetrics and Gynaecology, 4th Ed

70. Thank
you