2. Learning Objectives
1) List common indications and contraindications for
induction of labor
2) Describe methods available for labor induction
3) Understand appropriate use of each method of
induction
4) Discuss challenges faced with labor induction
3. What is IOL?
Definition
Artificial stimulation of uterine
contractions before spontaneous onset of
labour with the purpose of accomplishing
successful vaginal delivery
4. Augmentation
Augmentation is the process of stimulation of the uterine
contraction that are already present but found to be
inadequate.
5. Indication
IOL is indicated when:
The benefits of delivery to the mother or fetus outweighs
those of continuing the pregnancy.
6. MATERNAL
Post-term pregnancy
PROM
Preeclampsia, eclampsia
Abruptio placenta
Chorioamnionitis
Medical conditions-
DM,Heart ds, Renal
ds,Chr. HT etc
FETAL
IUFD
Fetal anomaly
incompatible with life
Severe IUGR without Fetal
compromise
Rh isoimmunisation
Macrosomia
Indications
7. CONTRAINDICATIONS
Any contraindication for normal vaginal delivery:
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
8.
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
Risks of IOL
9. 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
Place of IOL_ where facility for Fetal monitoring & intervention
is available
10. 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 anterior
Modified Bishop’s Score
• Unfavorable cervix: Bishops score less than or equal to 6
– Probability of vaginal delivery is lower if labor is induced
• Favorable cervix: Bishops score greater than 8
• In general: Patient’s with an unfavorable cervix will benefit from
initiation with cervical ripening
12. 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.
13.
14. Risks of this technique include:
infection,
bleeding,
accidental rupture of the membranes,
patient discomfort
15. Increased likelihood of spontaneous labor in 48
hours or delivery within 1 week
Compared to no intervention, reduced frequency of
pregnancy continuing beyond 41 weeks 42 weeks
Reduced frequency for formal induction compared to
no intervention
16. Amniotomy
• Deliberate rupture of the amniotic sac to
induce or expedite labor
• Ensure head is well applied to reduce risk of
prolapse of cord or fetal part
17.
18. Risks associated with this procedure include:
umbilical cord prolapse or compression,
maternal or neonatal infection,
FHR deceleration,
bleeding from placenta previa or low-lying placenta, and
possible fetal injury.
19. In one RCT, routine early amniotomy in nulliparous labor
induction shortened the time to delivery by > 2 hours and
increased the proportion of deliveries within 24 hours
20. • May place during digital
exam or with speculum
using a ring forceps or
urologic sound
• May leave in place until
extruded or for up to 12
hours
• Goal is to have
intrauterine balloon
distended with saline
and retracted so it rests
against the internal os
Balloon Catheters
21.
22. Misoprostol
• Prostaglandin E1
• Brand name: Cytotec
• FDA approved for treatment and prevention of
gastric ulcers
• Off label use for labor induction in women
without history of cesarean section
23.
24. • Available in 100 mcg and 200 mcg tablets
• Route: oral, sublingual, buccal or vaginal
• Typical use:25mcg vaginally every 3-6 hours
25. Outcomes using vaginal misoprostol
• Compared to no treatment/placebo
– Improved rates of vaginal delivery within 24 hours
• Compared to other prostaglandins
– Decreased risk of failure to achieve vaginal delivery within 24
hours
– Decreased need for oxytocin augmentation
• Compared to balloon catheters
– No statistically significant difference in likelihood of vaginal
delivery within 24 hours
– No statistically significant difference in cesarean delivery rates
• Compared to oxytocin
– Reduced risk of failure to achieve vaginal delivery in 24 hours
– Reduced cesarean delivery rate
26. Dinoprostone
• ProstaglandinE2
• Brand Names:
– Prepidil: Gel, contains 0.5 mg dinoprostone in 2.5
mL of gel
– Cervidil: Vaginal insert, contains 10 mg dinoprostone
in time release formulation (0.3 mg/h)
_ Prostin : Vaginal Tab (3mg)
27.
28. Outcomes using dinoprostone
• Compared to placebo/no treatment
– Reduced likelihood of vaginal delivery not achieved in 24 hours
Reduced rate of continuation of unfavorable cervix after 12-24 hours
– Reduced need for oxytocin augmentation
• Compared to balloon catheters
– Proportion of women who did not achieve vaginal delivery within 24 hours
was not significantly different
29. Risks of Prostaglandins
Nausea, vomiting, diarrhoea
Bronchospasm
Tachysystole
Hyperstimulation of Ut
Fetal distress
Ruptured uterus
30. Oxytocin
• Synthetic analog of oxytocin
• Mechanism of action
– Stimulates uterine contractions by activating G- protein coupled
receptors that trigger increases in intracellular calcium levels in
uterine myofibrils
– Increased local prostaglandin production, further stimulating uterine
contractions
• In general, less successful when used in women with a low Bishop
score, and as such, a ripening process should be used prior to
administering oxytocin to women with unfavorable cervixes
31. • For IOL, typically given IV
• Low dose and high dose protocols
given through infusion pumps
• Goal to have strong contractions
every 2-3 minutes
• No benefit in increasing dose
when one of these endpoints is
achieved
33. If induction fails, decisions about further management
should be made in accordance with the woman's wishes,
and should take into account the clinical circumstances.
If induction fails, the subsequent management options
include:
_a further attempt to induce labour (the timing should
depend on the clinical situation and the woman's wishes)
_caesarean section
