NORMAL LABOUR BY WISEMAN CHANDA

1. By Dr ALEX NIYIBIZI, MD
CUST

2. CONTENT
 Case presentation
 Literature review
 References

3. Objectives
At the end of this course the student should be able:
• Understand systematic way to determine the fetal lie,
presentation, position, attitude and station.
• Understand the proper definition of labor.
• Understand changes occurring about the cervix during
lobor.
• Understand the four stages of labor.
• Understand the cardinal movements of the fetus
during delivery.

4. CASE PRESENTATION
 N.V 29 y.o female admitted on 14/12/2012 @ 4:10 AM
 CC: lombopelvic pain for 7H on a pregnancy of 38 WA
 ATCDs:
 G1P0, LMP: 22/03/2012, EGA: 38W
 ANC 7x
 No pathology during pregnancy
 No remarquable surgical history
 BG: A+
 HIV status –

5. Case cont’
P/E:
BP: 120/78 mmHg, P: 80bpm, Wt: 78kg, Ht: 162cm,
BMI: 29.7
CV and Respiratory system: NAD
Abdomen: soft, gravid uterus of SFH of 36 cm
Leopold maneuvers revealed a longitudinal
lie and cephalic presentation, 1 weak
and irregular contraction. FHR: 140 bpm

6. Case cont’
Pelvic:
 cervix dilated at 2 cm, soft, posterior, and effaced for
40% with engagement of 5/5.
 uterus was increased in volume, soft and immobile.
 Pelvimetry: obstetrical conjugate > 11 cm, innominate
lines followed on anterior 2/3, subpubic angle was
large and interspinous diameter of around 10 cm

7. Case cont’
Conclusion: latent phase of labor
Plan: let labor progress
Do obstetrical U/S and FBC
 U/S: IU monofetal pregnancy, CA+, FM+, AF suff,
placenta anterofundic grade II,
BPD: 94 cm, HC: 324 cm, AC: 314 cm, Fl: 73.5 cm
USMA: 36W6d, EFW: 2929±460 gr
 Hb: 13.9g/dl

8. Time Contractio
ns
Cervix Engageme
nt
FHR Action
/plan
9:40 AM 2 weak and
irregular
Dilatat:2cm
Effacnt:
50%
5/5 140 bpm Monitor
FHR and
contraction
s
5: 40 AM 2 weak and
irregular
Dilatat:
3cm
Effacnt:
60%
4/5,
membranes
intact
136 bpm Monitor
FHR and
contraction
s
7: 15 PM Dilatat:
3cm
Effacnt:
70% some
cervical
edema
4/5 148 bpm R/
buscopan
40mg IVD,
AROM with
clear fluid
Monitor
labor
9:13 PM 2 regular
but weak
Dilatat:
5cm
Effacnt:
4/5 140bpm R/ ocytocin
5 IU/ 500ml
8d/min to

10. Case cont’
 @ 01:10 AM, 3 regular and strong contractions with fully
dilated and effaced cervix, FHR of 140 bpm descent 2/5
Plan: prepare for delivery
 @ 01:28 AM, delivery of a female baby of 2800 gr APGAR
10/10 with episiotomy. Oxytocin 10 IU IM is given
 @ 01:40 AM, spontaneous delivery of placenta.
 Normal and complete placenta tissues
 Suture of episiotomy
R/ ampicillin 2gr IVD. Uterus is well retracted

11. Time VS Uterus Vaginal
bleeding
Colustru
m
Fetus apprecia
tion
2:00 AM BP: 110/70
P: 92 bpm
Well
retracted
minimal present Normal
reflexes
Normal
PP
2:15 BP: 105/70
P:90 bpm
Well
retracted
Minimal present Normal
reflexes
Normal
PP
2:30 BP:
P:
Well
retracted
Minimal present Baby is
sucking
Normal
PP
2:45 BP:
P:
Well
retracted
Normal
lochia
present Normal
reflexes
Normal
PP
3:00 BP:
P:
Well
retracted
Normal
lochia
present Normal
reflexes
Normal
PP
Good
evolution

12. Case cont’
 In summury:
 1st stage: from 4:00 AM- 12:00 PM ( 20H)
 Latent phase: 17H
 Active phase: 3H ( 2cm/h of cervical dilatation)
 2nd stage: from 12:00 PM- 1:30 PM ( 1H30min)
 3rd stage: from 1:30- 1:40 PM ( 10 Min)

13. Normal labor and delivery cont’
DEFINITION OF LABOUR
 progressive DILATATION and EFFACEMENT of
cervix,
normally associated with DESCENT of presenting part
• preterm (> 20 but < 37 weeks GA)
• term (37-42 weeks)
• post-term (> 42 weeks)
 Braxton-Hick contractions: irregular, occur
throughout pregnancy and not associated with any
dilatation, effacement or descent

14. PHYSIOLOGIC PREPARATION FOR
LABOR
 Lightening
 Braxton Hicks contractions occur during the last 4-
8 weeks
 Cervical changes during the course of several days to
several weeks before the onset of true labor
 Bloody show following cervical changes and onset of
labor associated with release of cervical mucus plug

15. DEFINITION
Characteristic True Labor False Labor
Contractions
Rhythm Regular Irregular
Intervals Gradually shorten Unchanged
Intensity Gradually increases Unchanged
Cervical dilatation Yes No
Discomfort
Location Back and abdomen Lower abdomen
Sedation No effect Usually relieved

16. Physiology of labor cont’
 Increased production of PGE2
 Increased concentration of oxytocin receptors in relation to
uterine distention
 As a result there is an increased response by the
myometrium to the oxytocin which then causes an increase
in the frequency and intensity of the contractions
 This causes an increase in the release of prostaglandins
from the placental membranes during the contractions.
 In this way, this process creates a continuous cycle of
activity that results in the development of labor.

17. Labor - Mechanics
Uterine contractions have two major goals:
 To dilate cervix
 To push the fetus through the birth canal
Success will depend on the four P’s:
 Powers
 Passenger
 Passage
 Psychosocial

18. Power
Uterine contractions
 Power refers to the force generated by the
contraction of the uterine myometrium
 Activity can be assessed by the simple observation
by the mother, palpation of the fundus, or external
tocodynamometry.
 Contraction force can also be measured by direct
measurement of intrauterine pressure using
internal manometry or pressure transducers.
 There is no specific criteria for adequate uterine
activity
 Generally 3-5 contractions in a 10 minute period is
considered adequate labor

19. Passage
Passage = Pelvis
 Consists of the bony pelvis and soft tissues of the
birth canal (cervix, pelvic floor musculature)
 Small pelvic outlet can result in cephalopelvic
disproportion
 Bony pelvis can be measured by pelvimetry but it
is not accurate and thus has been replaced by a
clinical trial of labor

20. Passage
 www.uptodate.com

21. Passage - Pelvimetry
 www.uptodate.com

22. Passenger
Passenger =fetus
 Fetal variables that can affect labor:
 Fetal size
 Fetal Lie – longitudinal, transverse or oblique
 Fetal presentation – vertex, breech, shoulder, compound
(vertex and hand), and funic (umbilical cord).
 Attitude – degree of flexion or extension of the fetal head
 Position
 Station – degree of descent of the presenting part of the
fetus, measured in centimeters from the ischial spines
 Number of fetuses
 Presence of fetal anomalies – hydrocephalus,
sacrococcygeal teratoma

23. Normal labor and delivery cont’
THE FETUS
Fetal Lie
• refers to the orientation of the long axis of the fetus
with respect to the long axis of the uterus
(longitudinal, transverse, oblique)
• transverse/oblique often due to uterine anomalies
(C/S if they don’t convert)
Fetal Presentation
• refers to the fetal part presenting at pelvic outlet
 breech (complete, frank, footling)

24. Breech(types)

25. Normal labor cont’
 cephalic
• vertex (area between fontanelles and laterally
by parietal eminences)
• brow/sinciput
• face
 shoulder
 compound (fetal extremity prolapses along with
presenting part)
• all except vertex are considered malpresentations (see
Abnormal Labour section)

26. Normal labour cont’
Fetal Position
• refers to position of fetal occiput in relation to maternal
pelvis
 occiput anterior (OA): commonest presentation
(“normal")
 occiput posterior (OP): most rotate spontaneously to OA;
may cause prolonged second stage of labour
 occiput transverse (OT): leads to arrest of dilatation
• normally, fetal head enters maternal pelvis and engages in
OT position
subsequently rotates to OA position or OP (in a small
percentage of cases)

27. Normal labor and delivery cont’
Attitude
• refers to flexion/extension of fetal head relative to
shoulders
 brow presentation: head partially extended (requires C/S)
 face presentation: head fully extended (mentum posterior
always requires C/S, mentum anterior will deliver
vaginally)
Station
• refers to position of presenting part relative to ischial
spines
 at ischial spines = station 0 = engaged
 2 cm below ischial spines = station +2

28. Normal labor and delivery cont’
THE CERVIX
 dilatation: latent phase: 0-3 cm; active phase: 4-10 cm
 effacement: thinning of the cervix (25%-50%-100%)
 consistency: soft vs. hard
 position: posterior vs. anterior
 application: contact between the cervix and
presenting part
 Note: For Bishop Score, see Induction of Labour
section

29. Normal labor and delivery cont’
FOUR STAGES OF LABOUR
 First Stage of Labour
 latent phase
• uterine contractions typically infrequent and irregular
• slow cervical dilatation (usually to 3-4 cm) and effacement
 active phase
• rapid cervical dilatation to full dilatation
(nulliparous ~1.2 cm/h and ~1.5 cm/h in multiparous)
• phase of maximum slope on Friedman curve (see Figure 6)
• painful, regular contractions ~q2 min, lasting 45-60 seconds
• contractions strongest at fundus, weakest at lower segment

30. Normal labour and delivery cont’
 Second Stage of Labour
• from full dilatation to delivery of the baby
• mother feels a desire to bear down and push with each
contraction
• progress measured by descent
 Third Stage of Labour
• separation and expulsion of the placenta
• can last up to 30 minutes before intervention indicated
• signs of placenta separation: gush of blood, lengthening of
cord, uterus becomes globular and fundus rises

31. Normal labor and delivery cont’
Fourth Stage of Labour
 first postpartum hour
 monitor vital signs and bleeding +/– oxytocin
 repair lacerations
 ensure uterus is contracted (palpate uterus and
monitor uterine bleeding)
 3rd and 4th stages of labour most dangerous to the
mother (i.e. hemorrhage)

32. Normal labor and delivery cont’
Course of normal labor
Stage Nulliparous Multiparous
First 6-18 hours 2-10 hours
Second 2-10 hours 5-30 minutes
Third 5-30 minutes 5-30 minutes
Fourth 1st hour post placenta delivary

33. STAGES OF LABOR
Stage Nulliparous Multiparous
1st 6-18 H 2-10 H
2nd 30 min- 3 H 5-30 min
3rd 5-30 min 5-30 min
Course of normal labor

34. First stage
 Latent phase:
 uterine contractions are infrequent and irregular
 slow cervical dilatation (usually to 3-4 cm) and
effacement
 Active phase: Friedman subdivided the active phase
into the acceleration phase, the phase of maximum
slope, and the deceleration phase

35. Friedman curve

36. First stage cont’
 rapid cervical dilatation to full dilatation
 nulliparous 1.2 cm/h,
 multiparous 1.5 cm/h
 painful, regular contractions q2-3 min, lasting 45-60
seconds
 contractions strongest at fundus, weakest at lower
segment

37. Second Stage of Labor
 This stage begins when cervical dilatation is complete
and ends with fetal delivery
 mother feels a desire to bear down and push with each
contraction
 progress measured by descent

38. Labor – Third Stage
 The time from fetal delivery to delivery of the placenta
 Three signs of placental separation:
 Lengthening of umbilical cord
 Gush of blood
 Fundus becomes globular and more anteverted against
abdominal hand

39. Labor – Third Stage
 Placenta is delivered using one hand on umbilical cord
with gentle downward traction. Other hand on abdomen
supporting the uterine fundus.
 Risk factor for aggressive traction is uterine inversion.
 Obstetrical emergency!!
 Normal duration between 0-30 min for both PrimiG and
MultiG
 From expulsion of the fetus to the delivery of the
placenta.
 can last up to 30 min before intervention indicated
 start oxytocin IV drip or give 10 U IM after delivery of
anterior shoulder

40. Fourth stage
 First postpartum hour
 monitor vital signs and bleeding
 repair lacerations
 ensure uterus is contracted
 inspect placenta for completeness and umbilical cord
for presence of 2 arteries and 1 vein
 3rd and 4th stages of labour most dangerous to the
mother

41. Labor
 Freidman’s curve
is a good
guideline for
expected
progression in
labor and
therefore helpful
to note abnormal
labor patterns.
Labor NulliG MultiG
1st Stage Active phase
Duration 6-18 h 2-10 h
Dilation ~1 cm/h ~1.5 cm/h
Arrested >2 h >2h
2nd Stage 0.5-3 h 5-30 min
3rd Stage 0-30 min 0-30 min

42. Cardinal movements of labor
 engagement,
 descent,
 flexion,
 Internal rotation,
 extension,
 external rotation, and
 expulsion

43. Engagement
The mechanism
by which the
biparietal
diameter, the
greatest
transverse
diameter in an
occiput
presentation
passes through
the pelvic inlet

44. Descent
Descent is brought about by one
or more of four forces:
1) pressure of the amnionic fluid,
2) direct pressure of the fundus
upon the breech with
contractions,
3) bearing down efforts of
maternal abdominal muscles, and
4) extension and straightening of
the fetal body.

45. Flexion
It occur as long as the descending
head meets resistance, whether
from the cervix, walls of the
pelvis, or pelvic floor
the chin is brought into more
intimate contact with the fetal
thorax
The shorter suboccipitobregmatic
diameter is substituted for the
longer occipitofrontal diameter

46. Internal
Rotation
With the descent of the
head into the midpelvis,
rotation occurs so that
the sagittal suture
occupies the
anteroposterior diameter
of the pelvis

47. Extension
When the head presses upon
the pelvic floor, two forces
come into play:
The first force, exerted by the
uterus, acts more posteriorly,
and the second, supplied by the
resistant pelvic floor and the
symphysis, acts more anteriorly
and result in extension.

48. External
Rotation
It brings bisacromial
diameter into relation with
the anteroposterior diameter
of the pelvic outlet

49. Expulsion
Anterior
shoulder is first
delivered, then
the posterior
After delivery of
the shoulders,
the rest of the
body quickly
passes.

50. MANAGEMENT OF NORMAL
LABOR AND DELIVERY
 At admission in labor ward:
 Maternal vital signs: BP, P, T, RR
 Vaginal Examination: Is performed unless there is
vaginal bleeding with unknown placenta site.
The number of vaginal examinations correlates with
infection-related morbidity, especially in cases of early
ROM.

51. At admission in labor ward cont’
 Laboratory Studies:
 FBC
 Proteinurie in hypertensive women only
 Women who have had no prenatal care should be
considered to be at risk for syphilis, hepatitis B, and
HIV tests. But also take Blood Group and Rhesus.

52. Management of the First Stage of
Labor
 FHR is checked at least every 30 min in 1st stage and every
15 min in 2nd stage in absence of any abnormality
 Evaluate the frequency, duration, and intensity of uterine
contractions.
 T, P, and BP are evaluated at least every 4 hours
 With prolonged ROM, defined as greater than 18 hours,
antibiotics for GBS prophylaxis is recommended
 Periodic pelvic examinations are performed at 2- to 3-hour
intervals to evaluate labor progress
 Bladder distension should be avoided.
 Secure iv line

53. Management of the Second Stage of Labor
 At this stage woman typically begins to bear down,
With descent of the presenting part, she develops the
urge to defecate
 A woman is not encouraged to push beyond the
completion of each contraction
 Get prepared for delivery
 Delivery of the Head:
 Perineum must be supported to prevent tear
 Aspirating the nose and mouth immediately after
delivery of the head.
 Ritgen maneuver allows controlled delivery of the
head.

54. Mgt of 2nd stage cont
 Delivery of the Shoulders:
 After delivery of the head, external rotation ( restitution)
occur.
 Gentle downward traction is applied until the anterior
shoulder appears under the pubic arch
 Next, by an upward movement, the posterior shoulder is
delivered
 Give oxytocin 10 IU IM after delivery of the shoulders.
 The rest of the body almost always follows the shoulders
without difficulty

55. Management of the Third Stage of
Labor
 Placenta separates within 30 min
 signs of placental separation:
 1. The uterus becomes globular and firm
 2. There is often a sudden gush of blood
 3. The uterus rises in the abdomen
 4. The umbilical cord elongates
 Uterine massage following placental delivery is
recommended

56. Mgt of fourth Stage of Labor
 The placenta, membranes, and umbilical cord should
be examined for completeness and for anomalies
 The uterus and perineum should be frequently
evaluated.
 Suture of episiotomy or lacerations if any
 Maternal VS should be recorded immediately after
delivery and every 15 minutes for the first hour.

57. In Summary
 Know the different stages of labor and their
management
 Know the labor curve
 Know the cardinal movements of labor
 Know the causes of postpartum hemorrhage

58. REFERENCES
 Cunningham, Leveno, Bloom,Hauth, Rouse, Spong:
Williams Obstetrics,23rd Ed. p374-405
 Alan H. DeCherney, MD, Lauren Nathan, MD, T.
Murphy Goodwin, MD, Neri Laufer, MD: Current
Diagnosis & Treatment Obstetrics & Gynecology.
 Toronto note
 Tamara L. Callahan MD, MPP, Aaron B. Caughey MD,
MPP, MPH, PhD: Blueprints Obstetrics and
Gynecology 5th Ed. P36-55

59. THANK YOU !