Induction of Labour Flashcards
What are indications for IOL?
Prolonged pregnancy e.g. > 12 days after EDD
Prelabour premature rupture of membranes, where labour does not start
Diabetic mother > 38 weeks
Rhesus incompatibility
HTN, pre-eclampsia, previous stillbirth, abruption, fetal death, placental insufficiency
What are CI of IOL?
Malpresentations (including breech) Fetal distress Placenta praevia Cord presentation Vasa praevia - fetal blood vessels run near internal os Pelvic tumour e.g. cervical fibroid
What is the Bishop’s score?
Helps assess whether IOL will be requried
What does Bishop’s score consider?
Cervical dilation
0cm, 1-2cm, 3-4cm
Length of cervix
>2cm, 1-2cm, <1cm
Station of head (cm above ischial spines)
-3cm, -2cm, -1cm
Cercial consistency
Firm Medium Soft
Position of cervix
Posterior Middle Anterior
0 1 2
What are the significance of Bishop’s scores?
Score < 5 indicates labour is unlikely to start without IOL
Score > 9 indicates labour will most likely commence spontaneously
If > 7, induction with artificial rupture of membranes should be possible, avoiding prostaglandins
How is IOL carried out?
Prostaglandin PGE2 as a pessary or vaignal gel
PGE2 may stimulate uterine contractions or precipitate labour
What happens after artificial or spontaneous rupture of membranes (amniotomy)?
Start intrapartum fetal heart rate monitoring using CTG
If the liquor is clear allow the woman to mobilise for 2-4 hours to allow spontaneous contractions to start
If she is not contracting after this time, start oxytocin IV in 0.9% saline using pump
What else can be used apart from PGE2, and oxytocin?
Misoprostol (prostaglandin E1 analogue) is as effective PO or PV
- only use for labour induction after intrauterine death
What are problems with induction
Failed induction Uterine hyperstimulation Iatrogenic prematurity Infection Bleeding - vasa praevia Cord prolpase C-section Instrumental delivery rates higher Uterine rupture
What is cord prolapse?
Umbilical cord depending ahead of the presenting part of the fetus
Can lead to cord compression or cord spasm, which can cause fetal hypoxia and damage or death
What are risk factors for cord prolapse?
Prematurity multiparity Polyhydramnios Twin pregnancy Cephalopelvic disproportion Abnormal presentation Placenta praevia Long umbilical cord High fetal station (cm above ischial spines)
When do most cord prolapsed occur?
Artificial rupture of membranes
What is management of cord prolapse?
Presenting part of fetus pushed back into uterus
Tocolytics may be used
Patient on all fours until preparations for immediate C-section have been carried out
Instrumental vainal delivery is possible if the cervix is fully dilated and the head is low
Incidence reduced by C-section in breech presentation
What is station?
Head in relation to ischial spine
Station is 0 when head is directly at level of ischial spines
-2 = 2cm above ischial spines
+2 = 2cm below ischial spines
Higher station = Higher Bishops score
