IOL (97-2003).pptx

OG

1. INDUCTION OF LABOUR Dr. Ei Shwe Syn JC CWH

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 1 2 3 DILATATION 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

11. NATURAL Breast/nipple stimulation Sexual intercourse Membrane stripping Amniotomy Acupuncture MECHANICAL Balloon catheters Lamineria tents Synthetic osmotic dilators CHEMICAL NONHORMONAL Herbs,evening primrose oil Homeopathic prep Enemas Castor oil HORMONAL Oxytocin Prostaglandins –PGE2,Misoprostol Relaxin Nitric oxide donors mifepristone Methods for Induction

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. Risks of this technique include: infection, bleeding, accidental rupture of the membranes, patient discomfort

14. 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

15. 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

16. 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.

17. 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

18. • 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

19. 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

20. • Available in 100 mcg and 200 mcg tablets • Route: oral, sublingual, buccal or vaginal • Typical use:25mcg vaginally every 3-6 hours

21. 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

22. 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)

23. 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

24. Risks of Prostaglandins Nausea, vomiting, diarrhoea Bronchospasm Tachysystole Hyperstimulation of Ut Fetal distress Ruptured uterus

25. 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

26. • 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

27. Failed IOL Failed induction is defined as labour not starting after one cycle of treatment

28. 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

29. Questions?