2. Induction of labour
Initiation of uterine contraction artificially after
the period of viability before onset of labour for the
purpose of secure vaginal delivery.
Augmentation of labour
The process of stimulation of uterine contraction
(both in frequency and intensity) that are already
present but found to be inadequate.
4. Induction of labour
Incidence 10%
The over all incidence increased globally.
According to National Center for Health Statistics
90/1000 live birth in 1989 to 184/1000 live birth in 1997.
5.
6. Indication of induction
obstetrics medical
Abruptio placentae
IUGR
Post maturity
Rh isoimmunisation
PROMS
Congenital anomaly
IUD
Oligohydramnios,polyhydra
mnios
Hypertensive disorders of
pregnancy
Diabetes mellitus
Chronic renal disease.
Cholestasis of pregnancy
7. CONTRAINDICATIONS OF
INDUCTION OF LABOUR
Contracted pelvis and CPD
Malpresentation (breech,tansverse lie or oblique lie)
Previous classical caesarean section or hysterotomy
Uteroplacental factors: Unexplained vaginal
bleeding,vasa previa,placenta previa
Active genital herpes infection
8. Contd…
High risk pregnancy with fetal compromise
Heart disease
Pelvic tumor
Elderly primigravida with obstetric or medical
complications.
Umbilical cord prolapse
Cervical carcinoma
9. PARAMETERS TO ASSESS PRIOR TO
INDUCTION OF LABOUR
MATERNAL FETAL
To confirm the indication for IOL.
Exclude the contraindication of
IOL.
Asses BISHOP SCORE (Score >6
favourable)
Perform clinical pelvimetry to
assess pelvic adequacy
Adequate counselling about the
risks,benefits and alternatives of
IOL with the woman and the
family members
To ensure fetal
gestatonal age.
To estimate fetal weight.
Ensure fetal lung maturation
status.
Ensure fetal presentation and
lie
Confirm fetal well being.
10. FACTORS FOR SUCCESSFUL
INDUCTION OF LABOUR
Parity
Period of gestation
Preinduction score
Sensitivity of uterus :positive oxytocin sensitivity test is
favourable for IOL.
Cervical ripening
Presence of fetal fibronectinin vaginal swab ( >50ng/ml)
11. Induction of labour two componant
Induction
of labour
Cervical
ripening
Dilatation of
cervix and
delivery
Uterine
contraction
12.
13.
14.
15.
16. Bishop’s score 1964
parameters score
0≥ 1 2 3
Cervical dilatation closed 1-2 3-4 5+
Effecement(%)
0-30
40-50 60-70 ≥80
consistancy firm median soft
position posterior midline anterior
station -3 -2 -1,0 +1, +2
Score 0-5 is unfavourable and 6-13 is favourable
Calder modification 1974 is effecement of cervix with length of cervix
Cervical length(cm) ≥4 2-4 1-2 <1
17.
18. METHODS OF INDUCTION
HISTORY :
Massage of breasts and uterus.
Stretching of the cervix digitally.
Rubber tubing pushed into the uterus.
Castor oil
Warm bath
Enema
19. Hot carbolic acid douche in 1856 by Scanzoni.
Kraus’ bougies
Rubber bags filled with water-Barnes(1861)
Artificial rupture of forewater-1st used by
DENMAN in 1756.
Hind water rupture by Drew-Smythe
catheter(1931)
20. METHODS OF INDUCTION
Medical induction :
o Prostaglandins PGE2,PGE1
o Oxytocin
o Other
:Mifepristone,oestrogen,corticosteroids,relaxin,Hyaluronid
ase under investigation.
Surgical induction :
o ARM
o Sweeping of the membranes.
o Balloon catheterization
22. OXYTOCIN
Occtapeptide, extracted from post. Pituitary 1906.
Blair Bell describe it application in pregnancy1909.
1910 used for augmentation of labour.
Used for induction of labour reported by Theobold 1952
chemical formula by Vincent de vigneaud (1953).
1968 Turnbull and Anderson introduced the tritration
methode for oxytocin administration
23.
24. Routes of administration:
Intravenous, intramuscular, Buccal, Transnasal
T (1/2) – 3-5mins.
Degraded by oxytocinase
Excreted by liver and kidneys.
Synthetic preparations: Syntocinon, Pitocin.
25. Oxytocin
Commonly used drugs for induction of labour inform of
dilute solution.
Steady plasma con. Reaches15-20 min of infusion but
recent studies shows it takes about 40 min (seitchik et
al.1984).
According ACOG 1999 two regimen.
Low initial dose @0.5-2mIU/mi n and slow increment at
every 15-40 min.
High dose start @3-6mIU/min with increment every 15-40
min.
RCOG 2001 recomends
Starting dose@1-2mIU/min & dose should be increased at
interval of 30 min.
26. Dose should be titrated against uterine contraction
aiming of 3-4 contractions every 10 min. that usually
develop with @12mIU/min
Max. licensed dose 20mIU/min
RCOG 2001 suggest max. dose 32mIU/min.
27. Oxytocin infusion for induction of labour using in
infusion set(5U/500ml)
Time since
induction
(min)
Dose of oxytocin
(mIU/min)
Rate of infusion
(ml/hr)
Total vol. infused
(ml)
00 1 6 0
30 2 12 3
60 4 24 9
90 8 48 21
120 12 72 45
150 16 96 81
180 20 120 129
28. Oxytocin infusion using a drip set
for induction of labour
Time since
induction
(min)
Oxytocin driprate
(drops/min)
Dose of oxytocin
(mIU/min)
Total vol. infused
(ml)
00 (2U/500ml) 10 2 0
30 20 4 15
60 30 6 45
90 40 8 90
120 50 10 150
150 60 12 225
180 (4U/500ml) 40 16 315
210 50 20 375
29. Complication association…
Uterine hyperstimulation more with high dose
regimen but increase chance of vaginal delivery
Uterine rupture.(to ↓risk, to be used carefully in grand
multipara and pre.cs, should not be started for six
hours following administration of vaginal
prostaglandin)
water intoxication (can be reduced by infusion with
electrolyte containing solution.)
Neonatal jaundice….. More study required.
32. PREPARATIONS AVAILABLE
Intra-cervical PGE2 Gel :
Dose : 0.5mg
Can be repeated every 6hrs and the max dose should not
exceed 3 doses in24 hrs.
Intravaginal application (RCOG 2001)
Dose-2mg in nulliparous women with unfavourable cervix
followed by a second dose 6-8 hrs later with a max dose of
4mg.
Multiparous women with favourable cx –Initial dose of 1mg
followed by a second dose 6hrs later
Max dose of 3mg (RCOG 2001).
33. Controlled released vaginal insert
10mg insert which releases
at the rate of 0.3mg/hr.
No prewarming required.
Patient should lie down for
2 hrs.
Insert removed after 12 hrs
or when active stage begins
or in case of
hyperstimulation.
34. Side effect: Uterine hyperstimulation
Contraindication
Established uterine activity.
Glaucoma
Asthma
Known hypersensitivity to prostaglandins.
Severe hepatic or renal impairment.
Active vaginal bleeding.
35. MISOPROSTOL :
Methyl ester of PGE1.
Has been used for patient with peptic ulcer ds.
since1988
Inexpensive.
Can be stored at room temperature.
48. Mechanism of onset of labor :
Streching of cervix
Separation of membranes
Reduction of amniotic fluid volume.
Used alone amniotomy is associated with unpredictable
and sometimes long intervals before delivery.
Amniotomy with oxyticin-shorter delivery intervals (ACOG
1999)
49. Advantages :
High success rate
Chance to observe the amniotic fluid for blood or
meconium.
Access to use fetal scalp electrode/intrauterine
pressure catheter/fetal scalp blood sampling.
51. IMMEDIATE BENEFICIAL EFFECTS OF ARM :
Lowering of BP in pre-eclampsia-eclampsia.
Relief of maternal distress in hydramnios.
Control of bleeding in APH.
Relief of tension in abruptio placentae and initiation
of labor.
53. COMPLICATIONS OF ARM :
Chance of umbilical cord prolapse
Chorioamnionitis
Accidental injury to the placenta,cervix or uterus,fetal
parts or vasa previa.
Liquor amnii embolism.
54. Sweeping of membranes
By inserting index finger
through the internal OS
as far as possible and
roatating twice through
360 degree to separate
the membrane from
lower segment
55. SWEEPING OF MEMBRANES
When performed as a routine policy at 38-40 wks of
gestation
Reduces the incidence of post-term pregnsncies one in
eight casees
Reduces the incidence of other methods of induction of
labour.
Not increases risk of maternal or fetal infection,
chorioamnionitis
……….cochrane review
56. COMBINED METHOD
The combined medical and surgical methods are
commonly used to increase the efficacy of induction by
reducing the induction-delivery interval.
61. FACTORS FOR SUCCESSFUL
INDUCTION OF LABOUR
Parity
Period of gestation
Preinduction score
Sensitivity of uterus :positive oxytocin sensitivity test is
favourable for IOL.
Cervical ripening
Presence of fetal fibronectinin vaginal swab ( >50ng/ml)
64. Failed induction
It is define when cervix failed to dilate 3-4 cm in 24
hours of induction.
what to do now??????....
option to wait– if no PROM and postponement is not
harmful for fetus as well as mother .
review the case if there is urgency caesarean section to
be done.
66. RESULTS OF INDUCTION
Proximity to term
Condition of the cervix
Method of induction
Station of presenting part
Amount of liquor drained
67. AUGMENTATION OF LABOUR
Introduced by O’Driscoll & his colleagues in 1968
Term ‘ACTIVE’ refers to the active involvement of the
consultant-obstetrician in the management of
primigravid labour.
68. When to augment ?
Dilatation does not increase @ 1cm/hr.
HOW AUGMENTATION IS DONE?
A standard concentration of 10u of oxytocin is used in all
circumstances.
Rate of infusion begins @ 10drps and increases by 10
drps at interval of 15 mins to a maximum of 60 drops.
69. Conditions to be fulfilled before
augmentation
Mothers must be nulliparous.
Vertex presentation.
Fetus must be single.
Memranes must be ruptured.
No evidence of fetal distress must be seen.
The progress of labour charted on a partograph.
Every mother not close to an easy vaginal delivery after
12hrs to be delivered by cesarean section.
70. AIM:To expedite delivery within 12hrs without
increasing maternal morbidity and perinatal hazards.
Objectives:
Early detection of any delay in labour.
Diagnose its cause.
Initiate management.
71. COMPONENTS OF ACTIVE
MANAGEMENT OF LABOUR
Prenatal education.
Admission to LR only after the diagnosis of labour.
Partographic monitoring of labour.
ARM with confirmation of labour.
Oxytocin augmentaion if cervical dilatation <1cm/hr.
Delivery completed within 12hrs of admission.
Fetal monitoring
72. Advantages :
Less chance of dysfunctional labour.
Shortens the duration of labour.
Fetal hypoxia can be detected early.
Low incidence of caesarean birth
Less analgesia.
Less maternal anxiety.
73. LIMITATION
Employed only in selected cases and in selected
centres where intensive intrapartum monitoring by
trained personnel is possible.
Notas del editor
Calder modification 1974 is effecement of cervix with length of cervix