Prolonged pregnancy & Induction of labour

1. Prolonged pregnancy &Induction of labour Dr. Samira Abudia MBBCH MD

2. Prolonged pregnancy vIntroduction:- qProlonged pregnancy is a condition that continuous to evoke anxiety in clinician and woman alike and is perceived as being a cause of increased risk to the fetus.

3. vobjective:- FOur aim from this lecture be able to: qUnderstand the definition of prolonged pregnancy and distinguish it from post maturity syndrome. qUnderstand the options in the management of prolonged pregnancy. qCounsel a woman about the risk of prolonged pregnancy.

4. vDefinition:- qThe standard international definition of prolonged pregnancy by WHO 42 completed weeks or more(294 days or more) from first day of last menstrual period.

5. vIncidence:- qBetween (4-14)% will reach this gestation. qIts recognized that woman who attend late for antenatal care may be unsure of her LMP. qDating by last menstrual period alone has 70% tendency to over estimate the gestational age (delayed ovulation).

6. Cont... qActual true rate is (3-5)% when based on ovulation date. qRoutine use of early ultra sound to calculate gestational age reduce incidence from 9.5% to 1.5%. qMost pregnancies that reliably 42 weeks probably are not biologically prolonged.

7. vAetiology and pathology:- qThe cause of prolonged pregnancy is not clear may represent simple biological variation. qProlonged pregnancy more common in PG. qProlonged pregnancy more common with H\O previous Prolonged pregnancy 30%. qInfant who suffered fetal distress at term had elevatedcortisol level.

8. Cont… qInfant who suffered fetal distress at prolonged pregnancy had reducedcortisol level. qRelative Adreno cortical insuffiency delay in onset of labour, increase risk of intra partum hypoxia, death in prolonged pregnancy. qAmniotic fluid fall in prolonged pregnancy. qNormal cardiac output. qDoppler velocimetry in uterine, umbilical, middle cerebral no difference from term pregnancy.

9. vClinical approach:- qAccurate diagnosis of prolonged pregnancy relies up on either accurate menstrual data or routine ultra sound in 1st or 2nd trimester before 20 weeks if she is not sure of her date of LMP.

10. A-History:- qConfidence in the menstrual history. qThe LMP tend to be accurate if:- wThe patient sure of her date. wThe pregnancy was planned. wThe cycle was regular. wNo resent history of oral contraceptive , abortion or lactation.

11. B-Clinical parameters:- q Uterine size ] vaginal examination in 1st trimester useful in determing gestational age. qFundal height ] abdominal examination. q Quickening ] maternal reporting first fetal movement. q Fetal heart ]heard by fetoscope at (18-20)weeks.

12. C-Ultra sound parameters:- rCrown-Rump length (CRL) at (7-10W) ±5days rBiparietal diameter (BPD) at (18-22W) ± 7days

13. Fetal and neonatal risks of prolonged pregnancy 1-perinatal morbidity & mortality is increased 2-3 times than normal. 2-post maturity syndrome: Post mature infant features include wrinkled, patchy, peeling skin along this body suggesting wasting. Occur in 20-30 % of prolonged pregnancy characterized by the following:- A-aging or infarction of placenta lead to utero placenta insuffiency which result in decrease oxygenation (fetal hypoxia) and decrease maturation (decrease sub cutaneous tissue).

14. B-oligohydramnious which cause umbilical cord compression. C-passage of meconium in utero. 3-macrosomic fetus: Weight >(4000-4500)gm occur in 70- 80% leads to: wabnormal labour. wshoulder dystochia. wbirth trauma.

15. Maternal risks of prolonged pregnancy q Psychological morbidity. The pregnancy is perceived by many woman as becoming high risk once EDD is passed. q Increased operative delivery (c\s). q Increased risk of hemorrhage (prolonged labour). q Increased risk of infection.

16. Management:- vSuccessful management of prolonged pregnancy depend on effective counselling of a woman and their full involvement in the decision making process. A-if the date are confirmed and the cervix are favourable. q Labour should be induced: wartificial rupture of membrane (AROM). wintra venous (IV) oxytocin. q Continous intra partum fetal monitoring watching for:- wvariable deceleration (cord compression). wlate decceleration (Utero Placental Insuffiency)(UPI).

17. B-if the date are confirmed and the cervix is unfavourable there is two options:- FInduce labour:- wusing prostaglandin E2. FConservation:- wboth the non stress test NST Amniotic fluid index AFI should be performed twice weekly. wDelivery should take place if the NST become non reactive or If the AFI is <5 cm or <2 cm depth of largest vertical pole.

18. C- if the date are uncertain:- wBoth the NST & AFI can be performed twice weekly while waiting for spontaneous labour to occur. wDelivery should take place if the NST become non reactive or if the AFI <5 cm.

19. Induction of labour

20. vDefinition:- qInduction of labour is the artificial initiation of uterine contractions prior to their spontaneous onset leading to progressive dilatation and delivery of the baby. vIncidence:- Variable (15-20)%.

21. vIndication:- qThe purpose of an induction is to achieve benefit to the health of the mother and or baby when their suspected or confirmed risk to mother and or baby.

22. 1-Maternal diseases :- w Diabetes. w Hypertention \ renal diseases. w cardiac disease. 2-pregnancy – related conditions:- w pre eclampsia. w intra hepatic choleostasis of pregnancy. w APH at term. w placental abruption. 3-fetal indication:- w intra uterine growth restricted. woligohydramnious. w Iso immunization.

23. 4- Pregnancy passing 41 weeks. 5- Pre-labour spontaneous rupture of membrane (PLROM). 6- Maternal request.

24. *Assessment before induction commence:- The obstetrician should assess the balance between the risk associated with allowing the pregnancy to continue and those associated with interrupting it: 1-confirmation of gestational age: to avoid risk of iatrogenic prematurity. wHistory – LMP. w Examination. wU\S Scan.

25. 2-Are there mechanical impedance to delivery?. w Disproportion. w Pelvic tumour. wPlacenta previa. 3- What is the condition of cervix assisted by bishop score (1964).

26. Bishop score

27. *Methods of induction:- 1-Medical :- w Prostaglandin. w Oxytocin. 2-Surgical :- w Membrane sweeping. w Amniotomy. 3-Combination 4-Agents currently researched :- w Nitric oxide donors. w Anti progestogens (Ru-486). w Inter-leukin-8. w Relaxin.

28. 1- Medical methods:- v If the cervix is unfavorable (un-ripe):- q prostaglandin: F local vaginal administration:- w tablet (0.5 mg). w pessary (3 mg). w gelly (1 mg). F side effect of prostaglandin:- w Gastro intestinal upset. w Uterine hyper stimulation (rare):- defined as six or more contractions in 10 minutes or a single contraction lasting >2 minutes.

29. vIf cervix is favourable (ripe):- q oxytocin: F its octa peptide hormone secreted from para ventricular and supra optic nuclei of hypothalamus, stored in posterior pituitary and released in pulsatile manner. F Oxytocin is administered in synthetic form pitocin or syntocinon used by continous I.V infusion (pump or drip) after amniotomy to stimulate uterine contraction, also used to augment and accelerate labour.

30. F The usual dose is 5 IU\500 ml normal saline. rate to be increased every 30 minute until satisfactory contraction are established. not exceeding 60 Drops\min or 32 m Unit \ minute. Fside effects:- wuterine hyperstimulation. wpoor uterine contraction. wAnti diuretic effect. w rupture of uterus. w Neonatal hyperbilirubinemia.

31. 2-Surgical methods:- A-membrane sweeping:- increased likelihood of spontaneous labour within 48 hours due to local release of prostaglandin. B-Amniotomy (AROM):- rFore-water amniotomy:- sAmniohook. sToothed forceps. rHind-water amniotomy:- sDrew-somyth catheter.

32. F The success of amniotomy is dependent upon the state of cervix, the parity of woman and the station of presenting part at time of intervention. rComplications:- w failure to induce effective contractions. w bleeding c damage to the cervix. w placental separation due to sudden reduction of the volume of liquor. w infections. w amniotic fluid embolism.

33. 3-combined surgical and medical induction:- Surgical amniotomy followed by oxytocin use.

34. THE ENDThanks for your attention