1、Prolonged Pregnancy,Dr Khaled Aba-Oub MD FRCOG Consultant O&G Tripoli Fertility Centre Consultant O&G St Helier Hospital,London UK,Posterm pregnancy is defined as a pregnancy that extends to 42 0/7 and beyond incidence: 3-12% however the actual biologic variation is likely less since the most freque
2、nt cause of a postterm pregnancy diagnosis is inaccurate dating,Fetal &Neonatal risks:Perinatal mortality rate at 42 wks is twice that at 40 wks increases to 4 folds 43 wks and to 5-7 folds at 44 wks,20% of postterm fetuses have post maturity syndrome,which is characterised with chronic intrauterine
3、 growth restriction from uteroplacental insufficiency.These pregnancies are at increased risk of umbilical cord compression from oligohydramnios,non-reassuring CTG,intrauterine passage of mec,hypoglycemia,seizures,and respiratory insufficiency,Macrosomia and bith injury fetal acidemia Neonatal death
4、 Cerebral palsy,Maternal Risksincrease in labour dystocia (9-12% vs 2-7% at term) Increase in severe perineal injury (3rd and 4th degree tears) related to macrosomia (3.3% vs 2.6% term) and operative vaginal delivery,and a doubling in the rate of Caesarean delivery (14% vs 7% at term) which is assoc
5、iated with higher risks of endometritis,haemorrhage,and thromboembolic disease,The emotional impact (anxiety and frustration) ofcarrying a pregnancy 1-2 weeks beyond theestimated du date should not be underestimated,20% of pregnant women will require IOL,the majority for prolonged pregnancy58% of wo
6、men will have delivered by 40 wks of gestation,74% by 41 wks of gestation and 82% by 42 wks of gestation,Ensure that the pregnancy has been dated correctly Dating U/S in the first trimester reduces rates of IOL for post-term pregnancy NICE advise U/S scans to determine gestational age using: CRL mea
7、surement from 10 wks 0 days to 13 wks 6 days Head circumference if CRL is above 84 mmU/S dating should not be postponed further than 24 completed wks irrespective of how sure women are of their menstrual dates,When to InduceWomen with uncomplicared pregnancies should be given every opportunity to go
8、 into spontaneous labour.Women with uncomplicated pregnancies should usually be offered IOL between 41+0 and 42+0 wks to avoid the risks of prolonged pregnancy,primarily increased intrauterine fetal death,If a woman chooses not to have IOL,her decision should be respectedFom 42 wks,offer increased a
9、ntenatal monitoring consisting of at least twice weekly cardiotocography and U/S estimation of maximum amniotic pool depth,Why offer IOLAs pregnancy continues,the risk of the baby dying in the uterus or soon after delivery increases The stillbirth rate increases fom 1 in 1000 37 wks of gestation to
10、3 in 1000 42 wks of gestation to 6 per 1000 43 wks of gestation,The reported complications of induction include:Hyperstimulation Fetal distress Failed Induction Caesarean Section Ruptured Uterus Adverse effects of drugs used for induction,Membrane sweeping:During vaginal examination,the clinicians f
11、inger is introduced into the cervical os,then the inferior pole of the membranes is detached from the lower uterine segment by a circular movement of the examining finger,Purpose:To initiate labour by increasing local production of prostaglandins and thus,reduce pregnancy duration or pre-empt formal
12、 IOL with either oxytocin,prostaglandins or amniotomy,Methods of IOL:Prostaglandins Oxytocin Misoprostol Isosorbide mononitrate Mechanical methods,Riks/Benefits of membrane sweepNo increased risk of C.S Membrane sweep reduces the frequency of pregnancy continuing beyond 41 and 42 wks No increase in
13、the risk of maternal or neonatal infection Discomfort during vaginal examination and other adverse effects (bleeding,irregular contractions) more frequently reported by women who undergo membrane sweep,Pre-Induction Assessment:Women are admitted to the maternity unit at around term plus ten days.A c
14、ardiotocograph (CTG) to ensure the fetus wellbeing is performedThis is followed by a vaginal examination to determine the modified Bishop score and act as a baseline against which to compare subsequent examinations,Prostaglandin induction is commenced on the antenatal ward,IOL should not occur on th
15、e antenatal ward if the pregnancy is high risk.These women should be induced on the LW After PG are inserted vaginally,the woman is asked to lie down for half an hour and a cardiotocograph is performed to establish fetal wellbeing;this is essential once uterine activity commences Oxytocin is administered on the LW with continuous fetal heart and uterine activity monitoring and with one to one midwifery care,Thank You,
