Induction and augmentation of labour by dr jograjiya
1.
2. Artificial stimulation of uterine contractions with or without
ruptured membranes at any time after the 28th week of
gestation by method that aims to secure a normal vaginal
delivery before the spontaneous onset of labor.
• Deferred until after the 36th week.
• Without any acceptable medical or obstetric indication.
Augmentation refers to stimulation of spontaneous
contractions that are considered inadequate because of failed
cervical dilation and fetal descent.
DEFINITION
3. To eliminate the potential risks to the fetus with
prolonged intrauterine existence while minimizing
the likelihood of operative delivery
Increasing trend globally.
According to the National Center for Health Statistics
90 per 1,000 live births in 1989
184 per 1,000 live births in 1997 (1).
The incidence of induction varies widely 5-30%.
GOAL AND INCIDENCE
5. Major degree of Placenta praevia
Major degree of cephalopelvic disproportion
Vasa praevia
Previous classical uterine incision
Cephalopelvic disproportion because of malpresentation or
abnormal pelvic bone structure
Active genital Herpes infection
Invasive cervical carcinoma
Hypersensitivity to cervical ripening agents
Transverse lie
Contraindications
6. ♪ Multiple pregnancy
♪ Polyhydramnios
♪ Grand multiparity
♪ Maternal heart disease
♪ Severe hypertension
♪ Breech presentation
♪ One or more previous cesarean section
♪ Abnormal fetal heart rate not requiring emergency cesarean
section
Conditions where IOL is not a true contraindication
but where special caution is required
7. Maternal Risks :
o Failure leading to Cesarean section
o Intrauterine infection, Chorioamnionitis
o Increased risk of post partum hemorrhage
due to Uterine Atony
o Uterine hyperstimulation
o Rupture uterus
o Amniotic Fluid Embolism
o Precipitate labor , Dysfunctional labor
o Increased risk of operative vaginal delivery
o Abruptio Placentae
o APH from undiagnosed placenta praevia
o Water intoxication
Risks
Fetal Risks :
o Fetal distress
o Fetal death
o Neonatal sepsis
o Iatrogenic delivery
of a preterm infant
o Cord prolapse
o Neonatal jaundice
o Increased risk of
birth trauma
8. ₤ Evaluate the indication
₤ Explain the indication of induction to the patient along with details of the
method to be used and take a written informed consent
₤ Assess adequacy of the pelvis and fetal size to r/o CPD
₤ Confirm the gestational age, fetal lie, and assess the fetal lung maturity # where
ever indicated
₤ Uterine activity and fetal heart rate should be continuously monitored. In case
of clinical auscultation, FHR should be heard during and for 1 minute after a
contraction at least every 15 minutes during the active phase of labor and after
every contraction in the second stage . Otherwise electronic fetal monitoring is
preferable
Partogram is to be maintained for active labour
Trained personnel and well equipped center
Pre- requisites for IOL:
9. # According to the ACOG Committee Opinion (2) , if one of the
following criteria are met then fetal maturity may be assumed and
amniocentesis need not be performed to confirm fetal maturity:
€ It has been 36 weeks since a positive serum or urine human
chorionic gonadotropin pregnancy test was performed by a
reliable method
€ An ultrasound measurement of the crown rump length,
obtained at 6-11 weeks, supports a gestational age of 39 weeks
or more
€ An ultrasound scan obtained at 12 to 20 weeks confirms the
gestational age of 39 weeks or more determined by clinical
history and physical examination
10. The uterine cervix has broadly two components which are:
a) cellular portion and,
b) extracellular matrix
The distal portion has greater connective tissue as compared to the part
close to the myometrium which is richer in the cellular component.
The cellular component has: smooth muscle cells, fibroblasts,
epithelium, and blood vessels. Cervical stromal cells produce
collagenases, elastases and metalloproteinaeses which are involved in
remodeling of the cervix. Fibroblasts also secrete cytokines like
interleukin 1 beta and interleukin -8
Structures and Physiology of cervical ripening :
11. collagen is in two forms Type I (70%) and type II (30%)
and is arranged in the form of a triple helix. In the non pregnant cervix
these are arranged in a dense and irregular fashion
these fibres are arranged parallel to and between the
collageAn fibres and play an important role in taking the pregnancy to
term by keeping the os closed
is a glycosaminoglycan and its relative proportion to
collagen is important in the remodeling of the cervix at labor.
is the most important proteoglycan which is
responsible for the increased water content of the cervix.
Extracellular matrix
a) Collagen:
b) Elastin:
c) Decorin:
d)Hyaluronic acid:
12. Collagen is reorganized and consolidated in early pregnancy with
proliferation and hyperplasia of the cellular component
Near the onset of labor, an overall decrease in the concentration of collagen
occurs with dispersion and remodeling into fine fibers, making the cervix
softer in consistency
Increases in decorin levels and physiologic cell death are in part responsible
for this process
Hyaluronic acid levels increase thereby increasing the water content of the
cervix and causes a loosening and dispersal of the fibers
Chemotactic response at term leads to an influx of neutrophils and an
increased levels of cyokines (interleukin 1 beta and interleukin –8 ) which in
turn release collagenases and elastases to allow effacement
Mechanical forces of uterine contractions extend the elastin and allow
dilatation
Changes during pregnancy:
13. PRE INDUCTION CERVICALASSESSMENT
It is known that success of labor induction is closely related to
ripeness of the cervix . Various scores have been proposed to
evaluate the cervical status.
a) Bishop’s Score : This was proposed by Bishop in 1964 (3)
and is the most widely used score. It was originally proposed
to determine the suitability of a patient for IOL in patients
who were parous, at term , had an uncomplicated pregnancy
and the fetus was in cephalic presentation.
14. Assessing Favor ability for Induction of labour
* A score of 9 or more ensured a safe and uniformly successful induction
Bishop Score
Factor/Score 0 1 2 3
Dilatation (cm) 0 1-2 3-4 5-6
Effacement(%) 0-30 40-60 60-70 80+
Station (cm) -3 -2 -1/0 +1/+2
Consistency Firm Medium Soft -
Position Posterior
Mid-
posterior
Anterior -
15. * Induction with a score of 16 more is considered favorable
Burnett (5) later on modified the original Bishop’s score giving a
maximum score of 2 to each of Bishop's five categories, giving a total
maximum score of 10.
He considered effacement in terms of length and not percentage and
considered previous term birth and cephalic presentation to be pre-
requisites for induction.
16. * Outcome of patients with a score of less than 6 was
unfavorable, with a score of 9- 10 all patients could be
delivered within 4 hours and most within 24 hours.
Modified ‘Bishop’ Score
Factor/Score 0 1 2 3
Dilatation (cm) <1 1-2 2-4 >4
Cervical length
(cm)
>4 2-4 1-2 <1
Station (cm) -3 -2 -1/0 +1/+2
Consistency Firm Moderate Soft -
Position Posterior Mid; Anterior - -
17. Evaluating the performance of Bishop's score, Lange et al (6)
observed that cervical dilatation was twice as important as the
other factors and proposed a modification of the original score
which predicted successful induction equally well.
Table 4. Pelvic Score Proposed by Lange et al
Factor/Score 0 1 2 3 Multiply by
Dilatation (cm) 0 1-2 3-4 5+ ×2
Cervical length (cm) 3 2 1 <1 ×1
Station (cm) -3 -2 -1 or 0 +1 or +2 ×1
21. TIME, PLACE & PREPARATION
Preferably early morning
Where facility for intervention
and fetal monitoring is available
Enema may be given to
patients prior to induction
Time of induction:
Place of induction:
Preparation of Patient :
25. MEMBRANE SWEEPING
¤ Its possible only if the cervix has
ripened to allow the passage of one
finger.
¤ Insertion of a gloved finger through
the cervix and it’s rotation against
the wall of the uterus.
¤ Its strips off the chorionic
membrane from the underlying
decidua releases PGS
¤ Placenta Previa should be
excluded, Accidental amniotomy is
a disadvantage.
26. Cervical ripening before labor induction in an unfavorable
cervix increases the success rates and shortens the induction to
delivery interval.
ᶲ Pharmacological methods (Prostaglandins, Oxytocin &
others)
ᶲ Non pharmacological methods (Natural, Surgical,
Mechanical and others)
CERVICAL RIPENING
27. PG E2 gel has been widely used for pre-induction cervical
ripening. Local applications of PGE2 causes cervical ripening
by three mechanisms:
♦ Alteration of extracellular grounds substance of cervix by
increasing collagenase, elastase, glycosaminoglycans,
dermatan sulfate, and hyaluronic acid levels
♦ Relaxation of smooth muscle of cervix
♦ Gap junction formation leading to initiation of uterine
contractions
PROSTAGLANDINS
28. Intracervical PGE2 gel: ( Cervigel , Dinoripe , Prepidil )
● Contains 0.5 mg of PGE2
● Bring the gel to room temperature before use and instill in the
cervical canal below the internal os
● The patient lies supine for 15-30 minutes after the insertion .
● If no response occurs in one use a repeat insertion may be required
after 6 hours
● Maximum of 1.5 mg or three insertions are allowed over a period of
24 hours.
● If required oxytocin is to used only after 6- 12 hours of the last
insertion.
Preparations available, Dosage and Usage Guidelines
29. Vaginal PGE2 gel :
contains 2.5 mg PGE2
2 doses 6 hours apart are used
Vaginal controlled release insert : (Cervidil )
10 mg insert which releases 0.3 mg / hr of the prostaglandin.
No need to pre warm the insert.
The patient should lie supine for 2 hours following the insertion.
The insert is to be removed after 12 hours or when active labor
begins or in case of hyperstimulation.
Intravaginal PGE2 gel
30.
31. ۩ Intracervical use is technically more difficult
۩ Vaginal route ( gel or insert ) is superior to intracervical route for
cervical ripening but it causes higher uterine activity
۩ Controlled release vaginal insert use gives a better post ripening score,
decreased the time to delivery, time to active labor and need for oxytocin
use as compared to vaginal gel 2 doses 2.5 mg six hours apart.
۩ The overall incidence of hyperstimulation is 4.8% - same as with
oxytocin. However , the incidence is more when used in active labor
(12.5 %) , more with vaginal gel (5%) than intracervical (1%) and least
with controlled release insert which can be reversed with terbutaline
administration or removal of the vaginal insert. Washing the vagina does
not offer any benefit
۩ Use of PGE 2 does not alter C. S. rates
PGE 2 Routes : Controlled trials : Some observations
32. CONTRAINDICATIONS
Established uterine activity
Glaucoma
Asthma
Severe hepatic impairment
Severe renal impairment
Known hypersensitivity to prostaglandins ,
Active vaginal bleeding
33. Side Effects
Uterine tachysystole has been reported to follow vaginally administered
prostaglandin E2 in 1 to 5 percent of women . Although definitions may vary among
studies, most use the terms defined by the American College of Obstetricians and
Gynecologists (1999a) to describe increased uterine activity as follows:
1.Uterine tachysystole is defined as 6 contractions in a 10-minute period.
2.Uterine hypertonus is described as a single contraction lasting longer than 2
minutes.
3.Uterine hyperstimulation is when either condition leads to a nonreassuring fetal
heart rate pattern.
Because hyperstimulation that can cause fetal compromise may develop when
prostaglandins are used with preexisting spontaneous labor, such use is not
recommended. If hyperstimulation occurs with the 10-mg insert, its removal by
pulling on the tail of the surrounding net sac will usually reverse this effect.
Irrigation to remove the gel preparation has not been helpful.
34. ACOG Guidelines : (14,15)
☼ Bishop’s score should be less than 4.
☼ Drug should be administered near the delivery suite.
☼ Patient should lie recumbent for 30 minutes after the
instillation.
☼ FHR and uterine activity should be monitored for 30
minutes to 2 hours after the instillation. After this, patient
may be transferred elsewhere, if there is no increase in
uterine activity and FHR is normal.
☼ The controlled release insert should be removed at the
onset of labor.
☼ Oxytocin should be avoided for initial 6-12 hours.
35. RCOG Guidelines : (16)
Intravaginal PGE2 should be used in preference to
intracervical preparations as they are equally
effective and administration of intravaginal PGE 2 is
less invasive of the vaginal preparations.
Tablets should be preferred over the gel as they are
more cheap and equally effective.
36. MISOPROSTOL
Mioprostol is a synthetic PG E1 analogue which has been
used as a gastric cytoprotective agent since 1988 for patients
of peptic ulcer.
Studies in late 1980’s and early 1990’s noted that oral
administration of this drug causes uterine contractions in
early pregnancy. Subsequent studies showed that intravaginal
misoprostol causes first and second trimester abortion and
there has been recent evidence of its use for cervical ripening
and labor induction.
37. Pharmacokinetics: The pharmacokinetics of misoprostol
have been extensively studied by Ziemann et al (17).
₵ They have observed that peak plasma concentration is
higher and achieved earlier after an oral administration.
₵ Peak levels with vaginal administration are attained more
slowly and sustained for longer periods because of the
presystemic gastrointestinal and hepatic metabolism that
occurs with oral route.
₵ Overall the systemic bioavailability is three times higher
with the vaginal route.
38. Dosage schedules and usage guidelines:
ⱷ Cheap drug
ⱷ Does not require storage conditions
ⱷ Can be given by oral, buccal or vaginal routes although
vaginal route is the most extensively used
ⱷ Tablets are available as either 100 mcg or 200 mcg
ⱷ Dosage: 25 –50 mcg is administered 4-6 hourly
ⱷ The tablet is inserted into the posterior vaginal fornix ,
one may or may not wet the tablet with saline prior to
insertion
39. Misoprostol : Controlled trials : some observations: (18)
Ʃ Oral route is not recommended at this point of time
Ʃ Misoprostol shortens the Induction delivery interval as compared to PG
E2 and oxytocin
Ʃ 25 mcg vaginal dose has less hyperstimulation but a longer IDI as
compared to 50 mcg
Ʃ It effectively lowers the cesarean rates
Ʃ However it is not recommended as an outpatient setting or with previous
C. S.
Ʃ An increase in the incidence of meconium staining of amiotic fliud and
tachysystole is noted
Ʃ Overall the use of misoprostol is not associated with an increased rate of
operative intervention for fetal distress and NICU admission.
40. ACOG Guidelines
Ω 25mcg should be the initial dose for labor induction at term,
should not be administered more frequent than 3-6 hours,
oxytocin should not be administered < 4 hours after the last
misoprostol use and the drug should be avoided in patients
with previous cesarean delivery or major uterine surgery.
Ω Use of higher dosage 50 mcg may be appropriate in some
situations and have a greater likelihood of vaginal delivery
within 12 hours, such doses increase the risk of
hyperstimulation and rupture.
Ω There is at present insufficient clinical evidence to address the
safety of misoprostol in patients with multiple gestations and
suspected fetal macrosomia.
41. RCOG Guidelines : (16)
Misoprostol appears to be more effective than oxytocin or vaginal PG E2 in presence
of ruptured membranes for induction of labor.
Use of misoprostol in obstetrics must be restricted to RCTs.
Oral misoprostol appears to be less effective than vaginal misoprostol, however, oral
route is associated with less incidence of uterine hypercontractility but a higher
incidence of meconium stained liquor.
Its use is associated with increased uterine hypercontractilty but this is not translated
in increased operative delivery rates. The safety issues surrounding the use of
misoprostol have not been clearly evaluated.
* Despite a lot of clinical use, misoprostol is still not approved by the Drug
Controller of India for use in induction of labor.
42. OTHER PHARMACOLOGICAL METHODS
Mifepristone: 200 mg misoprostone for 2 days has been recently used for
cervical priming (23). However this method is not cost effective and needs
further trials.
Relaxin: Relaxin has been demonstrated to causes changes in the collagen
resulting in cervical softening . Both purified porcine and DNA produced human
relaxin have been tried with success in promoting cervical ripening with no
adverse maternal and fetal outcomes (24,25) . It is not yet commercially
available.
Nitric Oxide: Animal studies have shown it to be a cervical ripening agent but
it is unlikely to be used for human use unless safety of NO in late pregnancy is
established
Cytokines: Theses are chemotactic agents which also can promote cervical
ripening by causing changes in the extracelllulaar matrix
43. NON PHARMACOLOGIC APPROACHES TO CERVICAL
PRIMING AND LABOR INDUCTION: (Natural, Surgical,
Mechanical and others):
NATURAL MODALITIES:
a) Herbal supplements: Commonly used herbal cervical ripening agents
include evening primrose oil, black cohosh, raspberry leaves. The liquid
of black cohosh is given as 10 drops sublingually hourly until the
cervical change occurs. Evening primrose oil is given as 3 capsules
orally daily for one week, this can be repeated for three such
administrations. red raspberry leaves also enhance uterine contractions in
a synchronous manner
b) Intercourse: results in a 10-50 fold increase in cervical mucus
prostaglandin concentrations which occurs after 2-4 hours and remains
for more than 12 hours duration. There is an associated increase in the
uterine contractile activity.
44. Hygroscopic dilators: These are natural or synthetic rods inserted through
the cervical os and left in situ for a particular time wherein because of their
osmotic properties they absorb endocervical and local tissue fluids . This
swelling causes a controlled dilatation of the cervix along with releasing
prostaglandins. Natural dilators are obtained from the seaweed Laminaria
japonicum.
Balloon devices : Foley’s catheter or designer balloon devices when inserted
intracervically can facilitate cervical ripening. Once properly placed ( beyond
the internal os) balloon or the catheter is inflated with 30-50 ml saline. It is
recommended to either attach a defined weight to the catheter end ( 1litre of
i.v. fliud ) or to use “gentle tugs” – 2 to 4 each hour until the catheter or the
balloon passes out (26,27) . Some recommend infusion of extra-amniotic
saline at the rate of 1 cc/minute. There is no infection associated with balloon
devices
MECHANICAL MODALITIES
46. Ideally amniotomy or ARM is performed when the cervix is effaced and
2 cm dilated but it can be performed with minimal cervical dilatation.
Methodology of ARM:
ψ Auscultate the FHR
ψ Evaluate the cervix and station of head. The cervix should be well
applied to the head
ψ Introduce two fingers into the cervix , sweep away the membranes
from the cervix
ψ Pass an Hook or Kocher’s forceps in between the groove of your two
fingers , hook the membranes and rupture them; look for the clarity of
liquor
AMNIOTOMY
47. Stretching of the cervix &
separation of the
membranes
Release of Prostaglandins
Depends on the state of
the cervix and station of the
presenting part
MECHANISM OF ACTION
48. CONTRAINDICATIONS:
☺IUD
☺Placenta praevia
☺Maternal HIV
☺Genital active herpes
infection
HAZARDS:
☺Cord prolapse
☺Amnionitis
☺Amniotic fluid embolism
☺Abruptio placentae
☺Bleeding through vasa
praevia
☺Maternal and fetal
infection
☺Fetal injury
ADVANTAGES:
☺ It shortens duration of labor
☺Allows for early diagnosis of meconium staining of amniotic
fluid, specially in high risk pregnancy
☺Facilitates invasive fetal monitoring Newer amnicot
49. OXYTOCIN
A polypeptide hormone
Secreted by the posterior pituitary gland
The drug was used intravenously in 1948 by Theobald et al (21) to
induce labor.
Later in 1958 Du Vigneaud et al (22) synthesized the drug.
Since then it has been the most commonly used drug for induction
and augmentation of labor.
Routes of administration:
Intravenous route being the most widely used.
It can be absorbed from the nasal or buccal mucosa, however when
given orally it is rapidly inactivated by trypsin.
50. The half life of oxytocin is 3-5 minutes. Once absorbed it is distributed in the extracellular fluid
and does not bind to plasma proteins and is excreted by the liver and kidneys.
The action is mediated by oxytocin receptors (OTR) which are present on the myometrium.
Myometrial response to oxytocin begins at 20 weeks , increases through out pregnancy and peaks
just before initiation of labor.
The response varies according to the status of the cervix, uterine sensitivity, variability in
oxytocin clearance rate, duration of pregnancy and the pre-existing myometrial contractions.
The OTR concentration is the rate limiting step for oxytocin action. Oxytocin on binding to the
OTR increases the intracellular concentration of calcium causing myometrial cell contraction.
Uterine contractions are also stimulated by a calcium independent mechanism involving the
prostaglandins. PGE and PGF are increased during oxytocin administration. It has been postulated
that Prostaglandin release by oxytocin is necessary for fully efficient uterine contractions during
labor.
PHARMACOKINETICS AND MECHANISM OF ACTION
51. Various Low- and High-Dose Oxytocin Regimens Used for Labor Induction
Regimen Starting Dose (mU/min)
Incremental Increase
(mU/min)
Interval (min)
Low-Dose 0.5–1.5 1 15–40
2 4, 8, 12, 16, 20 25, 30 15
High-Dose 4 4 15
4.5 4.5 15–30
6 6* 20–40@
DOSING AND USAGE GUIDELINES:
10 –20 units are dissolved in 1000 ml of balanced salt solution ( Ringer Lactate solution or
Normal saline ) making it as 10-20 mu/ml and it is preferable to give it through an infusion
pump. Further increments are made according to the low dose or high dose protocol given
below (15 ) :
*With hyperstimulation and after oxytocin infusion is discontinued, it is restarted at 1/2 the
previous dose and increased at 3 mU/min incremental doses.
@Hyperstimulation is more common with shorter intervals.
52. After intravenous infusion, uterine response occurs
within 3-5 minutes and a steady state plasma
concentration is reached in about 40 minutes.
The end point to be achieved is uterine contractions
every 2- 3 minutes lasting for 60-90 seconds and a
uterine pressure of 50- 60 mm Hg or 150 Montevideo
units.
53. ☻ Hyperstimulation , with or without fetal heart rate
changes
☻ Failed induction with need for repeat induction or
possibly cesarean
☻ Increased risk for uterine rupture in some studies
☻ Hypotension if administered by IV bolus
☻ Hyponatremia if administered with large amounts of
sodium poor fluids
☻ Antidiuretic hormone like effect if administered at high
doses
☻ Increased risk for neonatal hyperbilirubinemia
RISKS OF OXYTOCIN
54. In the management of active-phase arrest, and with no
contraindication to intravenous oxytocin, decisions must
be made with knowledge of the safe upper range of uterine
activity.
Importantly, despite no labor progression, there were no
adverse maternal or perinatal effects in those undergoing
cesarean delivery.
There are no data regarding safety and efficacy of
contraction patterns in women with a prior cesarean
delivery, with twins, or with an overdistended uterus.
55. First-stage arrest of labor is defined by the
American College of Obstetricians and Gynecologists
(1989, 1995a) as a completed latent phase along
with contractions exceeding 200 Montevideo units
for more than 2 hours without cervical change.
Some investigators have attempted to define a more
accurate duration for active-phase arrest.
Duration of Oxytocin Administration—Active Phase Arrest
56. Rouse and colleagues (1999) prospectively managed 542 women
at term with active-phase arrest and no other complications.
Their protocol was to achieve a sustained pattern of at least 200
Montevideo units for a minimum of 4 hours.
This time frame was extended to 6 hours if activity of 200
Montevideo units or greater could not be sustained. Almost 92
percent of these women were delivered vaginally.
These and other studies support the practice to allow an active-
phase arrest of 4 hours (Rouse and associates, 2001).
57. MONTEVIDEO UNITS :
No of contractions / 10 MIN
X
Avg, intensity of contractions in mm of hg
Eg : 3 X 60mmHg = 180
Uterine activity – Spontaneous labour - 200 MVUs
Induction of labour - 250 – 275 MVUs
How do we calculate uterine activity ?
58. RCOG Guidelines : (16)
Oxytocin should not be started for 6 hours following
administration of vaginal prostaglandins
In women with intact membranes , if feasible amniotomy
should be performed prior to commencement of oxytocin
infusion
Minimum possible dose of oxytocin should be used and
titrated against uterine contractions. Maximum licensed dose
is 20 mU/min and should not be exceed 32 mU/min
Local protocols should specify the dose , dilution of oxytocin
and preferably be delivered via infusion pump or syringe
driver with non-return valve
59.
60. Infusion pumps is an electronic apparatus designed
to deliver drugs and 'biologicals', at low doses.
The delivery process of these pumps are associated
with local hemolysis which consists the potential
benefits of a calibrated delivery system.
Infusion pumps are easy to use as these are
designed keeping in mind the requirements of
patrons at our vendors' end.
61. 1. Oxytocin for the purpose of induction or augmentation of labor, will be
ordered by the physician and administered by an RN.
2. Oxytocin administered for induction or augmentation of labor will be
performed only in L&D after a minimum 30 minute baseline FHR and UA
tracing is obtained.
3. A registered nurse is responsible for the operation of the pump
(adjustments to infusion rate per MD order).
4. Continuation of an oxytocin infusion beyond 20 milliunits/min requires an
MD order.
5. In accordance with ACOG recommendations, the practice of elective*
delivery prior to 39 weeks gestation is prohibited (unless approved by
Chairman/Clinical Chief).
*An elective delivery is a delivery prior to 39 weeks gestation without a valid
medical or obstetrical indication
Oxytocin Administration via the Infusion Pump
64. MISCELLANEOUS:
a) Castor Oil (28 ) : It is an extract from “Ricinus
communis” and is mainly crude ricinoleic acid. It is known to
stimulate gut peristalsis and labor most likely is stimulated
due to release of prostaglandins. The method is no longer
used now. One study has reported an increased incidence of
meconium staining of amniotic fluid.
b) Acupuncture and TENS (Transcutaneous electric nerve
stimulation): Few studies ( 29-31) have reported successful
induction of labor with these methods but further trials are
needed before planning a large scale use.
65. a) Previous C. S. :
» One or more previous C. S. are not a contraindication to the
induction of labor.
» Cervical ripening can be done in these situations with
PGE2 gel – either intravaginal or intracervical
» Misoprostol is an absolute contraindication
» Oxytocin can be safely used in low doses with close
monitoring of uterine contractions and FHR.
» It is preferable to have continuous electronic fetal
monitoring.
CERVICAL RIPENING AND IOL IN SPECIAL
CIRCUMSTANCES
66. b) Twin pregnancy:
› PGE 2 gel can be safely used for cervical ripening
› ARM facilitates induction
› Oxytocin in low doses can be used
c) Premature rupture of membranes (PROM) :
› Use of PGE2 gel– 2 doses 6 hours apart is not associated
with higher incidence of infection
› Misoprostol can also be used in 25 mcg dose
› Oxytocin infusion should be closely monitored
› Beware of hyperstimulation
67. d) Intrauterine fetal demise (IUFD ) :
♫ Oxytocin is effective for IOL near term with a favorable
cervix.
♫ All prostaglandins can safely be used in recommended
dosages for cervical ripening remote from term.
68. It is defined when Cx failed to dilate up to 3-4 cm in 24
hrs 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 and if there is urgency,
Caesarean delivery is performed.
Failure of Induction
69. MONITORING UTERINE CONTRACTIONS
Intra uterine pressures
FETAL MONITORING
Fetal pulse oximetry
Fetal electrocardiogram wave form analysis
Intermittent measurement of lactate by FBS
As an adjuvant to
EFM as it has high False positive rates
What's new in monitoring of labour ?