Medical & Other Methods of Induction
Cervical Ripening Methods: Softening the cervix when it is 0-3cm dilated and long
1) Stretch & Sweep
Cervix should be slightly dilated (open) and softened. It is done by manually sweeping a finger around the cervix to separate the membranes of the amniotic sac from the cervix. It may or may not be repeated. Risks include discomfort, bleeding, cramping, risk of infection, premature rupture of membranes.
3) Foley Catheter
Used when the cervix is not sufficiently softened or dilated (must be open enough to insert the catheter). It is done by inserting a balloon catheter into and past the cervix, inflated with sterile fluid to a size that would stay on the cervix to apply pressure and encourage dilation. This requires 20 minutes of continuous fetal monitoring before and after insertion. After insertion and monitoring, the client is discharged home for 12-24 hours. This can be done at the clinic, the Ottawa Birth and Wellness Centre, or the hospital. The catheter usually falls out around 3-4 cm dilation or is removed after 12-24 hours by the midwife, followed by other induction methods if necessary. Risks include discomfort, infection, rupture of membranes, bleeding.
2) Prostaglandin (Cervidil / Prostin Gel)
Used when the cervix is not sufficiently softened or dilated. It is done by inserting of a prostaglandin in the vagina and placed near the cervix to soften and dilate it. It is performed at the hospital in triage & requires 20 minutes of fetal heart rate monitoring before and 1 hour post insertion monitoring. Risks include uterine hyperstimulation (more than 5 contractions in 10 minutes), fetal distress, nausea, vomiting, diarrhea, fever.
4) Misoprostol
Used when the cervix is not sufficiently softened or dilated (open); may be used after prostaglandin or foley; can be used if your water has broken and you are not contracting. Checking the cervix is not always needed to start this medication. This involves swallowing a synthetic prostaglandin (tablet). You must be admitted to the the hospital to allow for closer monitoring of contraction pattern and fetal heart rate. Assessment would occur every 2 hours. Other methods could be used if needed. Risks include uterine hyperstimulation (more than 5 contractions in 10 minutes), fetal distress, nausea, vomiting, diarrhea, shivering, chills, fever.
1) Artificial Rupture of Membranes (AROM)
To do this, the cervix should be sufficiently dilated (open), usually at least 2-3 cm dilated. It involves manually breaking the amniotic sac with a small hook (looks like a crochet hook) during a vaginal exam to stimulate contractions. Assessment is immediate to ensure fetal wellbeing, as well as colour and amount of fluid. Reassessment is typically within a few hours. Risks include infection, umbilical cord prolapse, discomfort, need for further interventions if labor does not progress
Augmentation: Promoting dilation after 3-4cm dilated
2) Oxytocin
Typically this is used as a last option, after other agents have been used, when the cervix is partially dilated and effaced (thinned out) but an effective contraction pattern has not yet been reached. It involves siting an intravenous catheter and administering a synthetic oxytocin (Pitocin) to stimulate uterine contractions. This requires hospital admission to ensure continuous fetal heart rate monitoring and contraction pattern. Risks include uterine hyperstimulation (more than 5 contractions in 10 minutes), fetal distress, water intoxication, nausea, vomiting, increased risk of instrument birth and cesarean section.
3) Misoprostol
May be used instead of oxytocin as an augmentation agent after cervix is >4cm but an effective contraction pattern has not yet been achieved. Oral administration of the tablet occurs every 2 hours until an effective contraction pattern has been achieved. Assessment is ongoing as it requires admission to the hospital. Risks include uterine hyperstimulation (more than 5 contractions in 10 minutes), fetal distress, nausea, vomitting, diarrhea, shivering, chills, fever.