Transcript INDUCTION OF LABOUR

INDUCTION OF LABOUR
Dr. Mona Shroff MD
www.obgyntoday.info
DEFINITION
Artificial stimulation of uterine
contractions before spontaneous
onset of labour with the purpose
of accomplishing successful
vaginal delivery
Dr Mona Shroff
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INDICATIONS
MATERNAL
Preeclampsia,
eclampsia
PROM
Postterm preg
Abruptio placenta
Chorioamnionitis
Medical conditionsDM,Heart ds,
Renal ds,Chr. HT
etc
Dr Mona Shroff
FETAL
 IUFD
 Fetal anomaly
incompatible with
life
 Severe IUGR
 Rh isoimmunisation
 Macrosomia
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CONTRAINDICATIONS
Severe degree CPD
Major degree placenta praevia
Transverse lie
Previous classical CS,Myomectomy
Previous>= 2 LSCS
Grand multiparity
Active genital herpes
Hypersensitivity to inducing agent
Dr Mona Shroff
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RISKS OF INDUCTION
Failure leading to CS
Uterine hyperstimulation
Fetal distress,death
Rupture uterus
Intrauterine infection,sepsis
Iatrogenic delivery of preterm infant
Precipitate/dysfunctional labour
Inc. risk of operative vaginal delivery
Inc. risk of birth trauma
Inc. risk of PPH
Dr Mona Shroff
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Adverse Effects
Tachysystole
Criteria: >10 contractions in 20 minutes
Dinoprostone Tachysystole Incidence: 33%
Misoprostol Tachysystole Incidence
Intravaginal gel or tablet: 31 to 49%
Oral crushed form or tablet: 16 to 22%
Dr Mona Shroff
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Hyperstimulation
Criteria
Exaggerated uterine response (i.e. Tachysystole)
Concerning Fetal Heart Rate tracing
Late Decelerations
Fetal Tachycardia >160 beats per minute
Dinoprostone Hyperstimulation Incidence: 17%
Misoprostol Hyperstimulation Incidence
Intravaginal gel or tablet: 8%
Oral crushed form or tablet: 1 to 2%
Uterine Rupture in VBAC
Risk: 2.5% in Trial of Labor after Cesarean
Dr Mona Shroff
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PREREQUISITES
Establish indication clearly
Informed consent
Conformation of gestational age
Assessment of fetal size & presentation
Pelvic assessment
Cervical assessment (BISHOPs score)
Availability of trained personnel
Dr Mona Shroff
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MOD. BISHOPS SCORE
SCORE
0
1
2
3
DILATATION
0
1-2
3-4
>4
EFFACEMENT
0-30%
40-50%
60-70%
>80%
STATION
-3
-2
-1/0
+1,+2,+3
CONSISTENCY
firm
medium
soft
POSITION
posterior mid
Dr Mona Shroff
anterior
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METHODS OF INDUCTION
NATURAL
Breast/nipple stimulation
Sexual intercourse
Membrane stripping
Amniotomy
Acupuncture/acupressure
CHEMICAL
MECHANICAL
Balloon catheters
Lamineria tents
Synthetic osmotic
dilators
HORMONAL
 Oxytocin
 Prostaglandins –PGE2,Misoprostol
 Relaxin
 Nitric oxide donors
 mifepristone
Dr Mona Shroff
NONHORMONAL
 Herbs,evening primrose oil
 Homeopathic prep
 Enemas
 Castor oil
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Stripping of the Membranes
Stripping of the membranes causes an increase in
the activity of phospholipase and prostaglandin as
well as causing mechanical dilation of the cervix,
which releases prostaglandins. The membranes are
stripped by inserting the examining finger through
the internal cervical os and moving it in a circular
direction to detach the inferior pole of the
membranes from the lower uterine segment.
[Evidence level C]
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contd.
Risks of this technique include infection, bleeding,
accidental rupture of the membranes, and patient
discomfort. The Cochrane reviewers concluded
that stripping of the membranes alone does not
seem to produce clinically important benefits, but
when used as an adjunct does seem to be
associated with a lower mean dose of oxytocin
needed and an increased rate of normal vaginal
deliveries. [Evidence level A, RCT]
Dr Mona Shroff
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Amniotomy.
It is hypothesized that amniotomy increases the
production of, or causes a release of,
prostaglandins locally. Risks associated with this
procedure include umbilical cord prolapse or
compression, maternal or neonatal infection, FHR
deceleration, bleeding from placenta previa or lowlying placenta, and possible fetal injury.
Dr Mona Shroff
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Balloon catheters
The Atad Ripener
Device in place with
the two balloons
inflated. The uterine
balloon is at the
internal os and the
cervicovaginal balloon
is at the external os.
Dr Mona Shroff
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Prostaglandins
M/A :Act on the cervix to enable ripening by a number of
different mechanisms.
They alter the extracellular ground substance of the cervix, and
PG increases the activity of collagenase in the cervix.
They cause an increase in elastase, glycosaminoglycan, dermatan
sulfate, and hyaluronic acid levels in the cervix. A relaxation of
cervical smooth muscle facilitates dilation.
 prostaglandins allow for an increase in intracellular calcium
levels, causing contraction of myometrial muscle..
Dr Mona Shroff
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contd.
Risks associated with the use of prostaglandins
include uterine hyperstimulation and maternal side
effects such as nausea, vomiting, diarrhea, and
fever.
Currently, two prostaglandin analogs are available
for the purpose of cervical ripening, dinoprostone
gel (CERVIPRIME: 0.5 mg ) and dinoprostone
inserts (PRIMIPROST :10 mg ).
Dr Mona Shroff
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Technique for Placement of Dinoprostone Gel
Patient selection: Patient is afebrile. No active
vaginal bleeding is present. Fetal heart rate tracing
is reassuring. Patient gives informed consent. Bishop
score is < 4.
Bring gel to room temperature before application, per
manufacturer's instructions.
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Initiate Fetal Heart Rate and tocometry
Start 15-30 minutes before gel inserted
Continue monitoring for 30-120 minutes after
Insertion Technique
Use one syringe of gel (0.5 mg )
Introduce gel into cervix
Just below level of internal os
Intracervical is preferred over posterior fornix (if leaking p/v
posterior Fx)
Patient remains supine for 30 minutes
Dr Mona Shroff
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Dosing
Repeat every 6 hours up to 3 doses in 24 hours
End points
Bishop Score of 8 or greater
Strong uterine contractions
Drug interactions
Wait 6-12 hours before starting Pitocin
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PGE2 GEL
Dr Mona Shroff
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