1. INDUCTION OF LABOUR

2. DEFINITION
Artificial stimulation of uterine contractions before spontaneous onset of labour with the purpose of accomplishing successful vaginal delivery

3. Induction Augmentation
it implies stimulation of contractions before the spontaneous onset of labor, with or without ruptured membranes.
Augmentation
It refers - intervention to correct slow progress in labor.
* Correction of ineffective uterine contraction includes Amniotomy and/or Oxytocin infusion

4. Physiological background
cervical ‘ripening’ is a physiological process occurring throughout the latter weeks of pregnancy and is completed with the onset of labour.
When delivery is necessary and ripening has not had time to occur, or has failed to be initiated, this natural process has to be accelerated.

5. Indications 1-Elective induction of labour
2-Indicated induction of labour
Elective induction
initiation of labor for the convenience
of an individual with a term pregnancy
which is free of medical indications.

6. Indicated Labor Induction INDICATIONS
MATERNAL
Preeclampsia, eclampsia
PROM
Postterm pregnancy
Abruptio placenta
Chorioamnionitis
Medical conditions-DM,Heart ds, Renal ds,Chr. HT etc
FETAL
IUFD
Fetal anomaly incompatible with life
Severe IUGR
Rh isoimmunisation
Macrosomia

7. PREREQUISITES Establish indication clearly Informed consent
Conformation of gestational age
Assessment of fetal size & presentation
(An engaged head in longitudinal lie).
Pelvic assessment
Cervical assessment (BISHOPs score)
Availability of trained personnel

8. Preinduction Cervical Ripening
The condition of the cervix—or "favorability"—is important to the success of labor induction.
One quantifiable method predictive of an outcome of labor induction is that described by Bishop (1964).

9. The Bishop’s score Cervix Head position -3 -2 -1 0 s c o r e s 0 1 2 3
Cervix
position posterior middle anterior
consistency firm medium soft
effacement (%)  80
opening (cm)  5
Head position
 5: unfavourable  6: favourable

10. Interspinal plane
Interspinal plane
Ischiadic spine

11. A score of 9 conveys a high likelihood for a successful induction
A score of 9 conveys a high likelihood for a successful induction. Most practitioners would consider that a woman whose cervix is
2 cm dilated, 80 percent effaced, soft, and midposition, and with the fetal occiput
at -1 station
would have a successful labor induction.

12. 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

13. When to induce
Recent studies have shown an increasing risk of infant mortality for births in 41st and particularly 42nd week of gestation, as well as a higher risk of injury to the mother and child .
The recomended date for induction of labor has therefore been moved
to the end of the 41 week of gestation in many countries

14. Method of induction

15. METHODS OF INDUCTION CHEMICAL NATURAL Balloon catheters
Breast/nipple stimulation
Sexual intercourse
Membrane stripping
Amniotomy
Acupuncture/acupressure
MECHANICAL
Balloon catheters
Lamineria tents
Synthetic osmotic dilators
CHEMICAL
NONHORMONAL
Herbs,evening primrose oil
Enemas
Castor oil
HORMONAL
Oxytocin
Prostaglandins –PGE2,Misoprostol
Relaxin
Nitric oxide donors
mifepristone

16. Several effective methods of cervical ripening and induction of labour are used for initiating labour at or around term. Currently, medical expert consensus recommends the following:
Sweeping the membranes
Artificial rupture of membranes (ARM)
Prostaglandin E2 (PGE2)
Intravenous oxytocin (Syntocinon®)

17. Prostaglandins
M/A :
Act on the cervix to enable ripening by a number of different mechanisms.
A relaxation of cervical smooth muscle facilitates dilation.
prostaglandins allow for an increase in intracellular calcium levels, causing contraction of myometrial muscle..

18. Contraindications
Known hypersensitivity to dinoprostone gel, Cervidil® pessary or its constituents (triacetin, colloidal silica or urethane)
History of previous uterine surgery including caesarean section
Dinoprostone gel - grand multiparity (five or more previous births)
Signs of fetal compromise on cardiotocography
Any contraindication to vaginal birth
Cervidil® pessary is contraindicated in multiple pregnancy or if the fetus is in a non-vertex presentation

19. Dosage and administration
Intravaginal mode of administration
Dinoprostone gel dosage
The initial dose for dinoprostone (PGE2) gel is 2 mg per vaginam (PV) in nulliparous women with an unfavourable cervix , 1 mg PV for multiparous women
o     A second dose of 1-2 mg of dinoprostone (PGE2) gel may be administered 6 hours later
o     The maximum dose in a 12 hour period is 4 mg PGE2 for nulliparous women with an unfavourable cervix and 3 mg for all other women

20. Before procedure:
o       Complete 20 minutes CTG tracing that fulfils the hospital’s accepted criteria
o       Ensure the woman has emptied her bladder
o       Confirm maternal pulse, blood pressure, respiration rate and uterine activity meet accepted criteria
o       Abdominal palpation to confirm cephalic presentation
o       Vaginal examination to obtain a modified Bishop score

21. Cervidil® pessary (10-mg dinoprostone vaginal insert)
o Single dose of 10 mg of dinoprostone (releases a mean dose approximately 4 mg dinoprostone over 12 hours) slower release than gel shorten the interval from induction-to-delivery can be removed (when hyperstimulation occur

22. Cervidil® pessary precautions
Remove pessary if:
o  Uterine hyperstimulation occurs
o    Labour becomes established
o   After SROM or before AROM
o   Syntocinon®  augmentation should not be commenced within 30 minutes of removal of Cervidil

23. After the procedure
o       Continue CTG monitoring for 20 minutes after insertion of dinoprostone gel / Cervidil® pessary. Discontinue CTG only if accepted criteria are met.
o       Perform regular observation of maternal pulse, blood pressure, respiration rate and FHR as indicated

24. Adverse effects
o Gastrointestinal (e.g. nausea, vomiting), back pain, fever. o Increased intraocular pressure in women with a history of glaucoma o Uterine hypercontractility (more than five contractions in 10 minutes, or contractions lasting more than 2 minutes) o Placental abruption or uterine rupture o Very rarely, genital oedema and anaphylactic reaction

25. Prostaglandin E1 (PGE1)
-Misoprostol (Cytotec) ` available as a 100 microg tablet for prevention of ulcer ` preinduction cervical ripening and labor induction → inexpensive stable at room temperature easily administered orally placed into the vagina but not cervix ` → intravaginal 25 microg every 3 to 6 hr

26. -tachysystole, meconium passage & aspiration
` if 50 microg dose,
-tachysystole, meconium passage & aspiration
increased c/sec rate (hyperstimulation)
: prior uterine surgery – risk of uterine rupture then
→ not use Misoprostol

27. Mechanical tecnique 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.
performed by inserting the index finger as far
through the internal os as possible and rotating
twice through 360 degrees to separate the
membranes from the lower segment

28. Contraindications: Low lying placenta Planned elective caesarean
Risks of this technique include
infection, bleeding, accidental rupture of the membranes, and patient discomfort.

29. Artificial rupture of membranes (ARM)
ARM is a surgical procedure to induce or augment labour
Amniotomy for induction
:used to induce labor but, it implies a firm commitment to delivery
:disadvantage
-the unpredictable and occasionally long interval to to delivery

30. Amniotomy for augmentation
when spontaneous labor is abnormally slow ((dysfunctional labor
with oxytocin- shortened labor by 44 minutes

31. Intravenous antibiotics in labour are recommended for
Women with clinically suspected chorioamnionitis
Women with maternal Group B Streptococcal vaginal colonization
So that Labour should begin within the next 12 hours and birth should occur within 18 hours to minimize the risk of ascending infection

32. Catheters.
Use of the Foley catheter technique alone, in which catheters are passed through an undilated cervix before inflation, was shown to be as effective as use of PGE2 gel.
The successful use of extra-amniotic saline infusion with a balloon catheter has also been reported
foley catheter with 30cc ballooning
-rapid improvement in Bishop score
shorter labor
-c/sec rate 4~46%

34. LABOR INDUCTION AND AUGMENTATION WITH OXYTOCIN
first polypeptide hormone synthesized
following delivery to induce or augment labor
Induction
stimulation of contraction before the spontaneous onset of labor, with or without ruptured membranes
Augmentation
stimulation of spontaneous contractions that are considered inadequate because of failure of progressive dilatation and descent

35. : oxytocin is avoided -abnormal fetal presentation uterine overdistention (hydramnios, large fetus, or multiple fetus) high parity ( >6 ) myomectomy)) previous uterine scar -not contraindication → prior cesarean delivery dead fetus unless CPD

36. Methods by infusion pump avoid bolus only IV route
: methods – diluted into 1000ml of a balanced salt solution ( lactated Ringer solution)
by infusion pump
avoid bolus
only IV route
 typically, 10~20 unit in 1000 ml
(10,000~20,000mU → 10~20 mU/ml)

37. Interventions if Uterine Hyperstimulation or Fetal Distress Occur:
4-Give oxygen 6 to 10 l/min ( per protocol) by face mask.
1-Turn off immediately oxytocin infusion
5-Notify experience doctor
2-Turn woman on her left side. .
3-Increase primary I.V rate up to 200 ml/hr unless contraindicated.

38. Other Complications may Occur during Oxytocin Infusion:
In addition to hyper-stimulation of uterus and fetal distress those complications may occur:
Ruptured uterus as a result of over-stimulation if any cephalopelvic disproportion present.
Amniotic fluid embolism is rare which may caused by strong, tumultuous contractions. (usually occur in 3rd stage after placenta separation and with tetanic condition of uterus)

39. Oxytocin dosage comparison ACOG
low-dose → 1mU/min, interval 20 mins
high-dose → 6mU/min, interval 20 mins
Max 42mU/min
if hyperstimulation, reduce 3mU/min
this flexible high-dose protocol
: delivery time ↓ forceps delivery ↓
chorioamnionatis ↓ neonatal sepsis ↓
but, c/sec ↑ (fetal disteress, 3% → 6%)

40. Recently explored methods
Antiprogestins
Epostane, the 3ß-hydroxy dehydrogenase inhibitor,
mifepristone, the progesterone receptor blocker, were shown to have a dramatic effect upon reducing induction to abortion intervals during second trimester therapeutic abortion

41. Dehydroepiandrosterone sulphate Intravenous dehydroepiandrosterone sulphate (DHEAS), which is transformed into oestrogens in the fetoplacental unit, has been explored as a possible cervical ripening agent, achieving effacement without inducing uterine contractions.
Relaxin This polypeptide has been studied in humans, using purified porcine relaxin 1–4 mg in viscous gel vaginally or endocervically. It was hoped that it would have the same properties as exhibited in certain animal species. To date, there have been no well-conducted trials to determine its value for ripening the unfavourable cervix

42. Nitric oxide There have been a number of studies suggesting that nitric oxide is involved in the process of cervical ripening during the latter stages of pregnancy.

43. GENERAL RISKS OF INDUCTION
Failure leading to CS
Uterine hyperstimulation
Fetal distress,death
Rupture uterus
Intrauterine infection,sepsis

44. Iatrogenic delivery of preterm infant
Precipitate/dysfunctional labour
Inc. risk of operative vaginal delivery
Inc. risk of birth trauma
Inc. risk of PPH

45. Failed induction
Failed induction is defined as labour not starting after one cycle of treatment
If induction fails, healthcare professionals should discuss this with the woman and provide support.
The woman’s condition and the pregnancy in general should be fully reassessed, and fetal
wellbeing should be assessed using electronic fetal monitoring.

46. For women who choose caesarean section after a failed induction,.
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
For women who choose caesarean section after a failed induction,

47. THANK YOU