Thinking about having a medical induction of labour? Or perhaps you already need one for a medically necessary reason.
There are several methods of induction of labour available to pregnant women.
The right method for you will depend on your unique situation.
For example, if your cervix is closed and not ripe (ready to dilate), your doctor will start with a cervical ripening medication.
If your cervix is open enough, your doctor may want to break your waters.
Or, your doctor may opt for medication in a drip, containing a synthetic version of the labour hormone, oxytocin.
There are pros, cons, risk and benefits to weigh up for each induction method.
Rest assured, BellyBelly is here to help. Below, you'll discover the four most common methods of medical labour induction, with information about how the procedures are performed, when they're used, and what the risks are.
While it may be hard to hear the risks (especially the more serious risks), it's still important information to be aware of. Knowing the risks as well as the benefits can help you to make more confident, informed decisions. You'll be able to work out what the safer option is for you and your baby. For example, you may decide the risks of an induction aren't worth it for your situation. Or, you may feel more confident proceding with a specific type of induction, which you feel to be the safest option for you and your baby. You don't need to be an expert.
One of the hardest things for pregnant women to do during labour is understand what's being offered and quickly work out what to do. But after reading this article, you'll feel more prepared.
Methods Of Induction Of Labour
Here are the four most common methods of induction of labour.
#1: Artificial Rupture Of Membranes (ARM)
The logic behind an artificial rupture of membranes (also known as an amniotomy) is once your waters have broken, the baby's head will put pressure on your cervix, resulting in your cervix dilating so you go into labour.
During an amniotomy, your doctor will insert a long, slim tool — called an amnihook — into your vagina. An amnihook looks similar to a long crochet hook, and it pierces the bag of waters surrounding your baby.
A rupture of membranes can only be performed if your cervix is partially open. If your cervix is closed, you'll need a ripening medication (usually prostaglandins) to help soften and open your cervix.
Your baby's bag of waters plays a very important role during pregnancy and birth. It's preferrable for the membranes to be in tact for as long as possible during labour, because there are risks involved when you have an amniotomy.
Once the membranes have been artificially broken, there's a risk of infection for the mother. The risk of infection is higher than the waters breaking on their own, and when you have fewer internal exams or procedures. For this reason, if you have an amniotomy, your doctor will want to give you antibiotics after a certain timeframe. This needs an article on it's own to explain how antibiotics impact both yours and your baby's gut bacteria. Many pregnant women suffer from thrush during pregnancy and after the birth, so avoiding needing antibiotics is something to consider.
If your baby is high or not engaged, cord prolapse can occur, which is where the cord comes out your vagina before the baby is ready to be born. This is a serious situation, as compression on the cord compromises the baby's blood and oxygen supply. There is also evidence that an amniotomy may trigger a stress response in the baby.
Despite it being a very common reason for an amniotomy being performed, there is no evidence that an amniotomy speeds up a labour which has already begun. There is also not enough evidence on using amniotomy alone for inducing labour. Other methods of induction are often used in conjunction with an amniotomy.
Main benefit: Non-drug induction method with a lower risk than other methods.
Main problem: The baby is no longer protected by the bag of waters and may have issues with position (easier to move with waters intact).
#2: Synthetic Oxytocin
One of the most common methods of induction is a synthetic labour hormone being administered via an IV line.
Synthetic oxytocin, which is called Syntocinon in Australia and Pitocin in the United States, is very effective at getting labour started.
Your doctor will book you into the hospital, and when you arrive, an IV line will be inserted into your hand. Then it's simply a matter of time until the hormone levels build up in your system to trigger labour. You may like to request a low dose to get started and see how things go – sometimes all women need is a little synthetic oxytocin and their labour is full steam ahead.
Once your labour has been started with synthetic oxytocin, you are well and truly committed to getting the baby out. It's likely you wont be able to have the drip turned off (although I have supported a client who was able to achieve this) but if you're not coping with the contractions, you may be able to have the drip turned down a little.Usually doctors don't want to turn off the drip, because they don't want labour to stop.
You'll also be monitored with an electronic fetal monitor, as you are now classed as high risk. With both the drip and monitoring attached to you, mobility becomes more difficult, and further interventions are likely. Epidurals, assisted birth (for example, episiotomy, forceps or vacuum) and c-sections are more likely with this method of labour induction.
Synthetic oxytocin doesn't work the same way as natural oxytocin – it doesn't cross the blood-brain barrier. Contractions are usually more intense, with not much of a break in between them. There is also an increased risk of complications including fetal distress and postpartum haemorrhage (PPH). Read more about the risks of induction of labour.
Main benefit: very effective induction method.
Main problem: further interventions are highly likely.
#3: Foley Balloon Catheter
Originally designed to empty the bladder, a Foley balloon catheter is an inexpensive, low risk option, especially for women planning a VBAC.
The reason why some doctors try to avoid using synthetic oxytocin to induce women with a previous c-section is because it can increase the risk of uterine rupture. The risk of rupture during a VBAC (vaginal birth after c-section) is very small at around 1%. However, when you add other factors which can increase the risk, it is wise to look at alternative induction options which have a lower risk.
Studies have found the foley catheter to be a safe induction method for women and babies, and because it's not a medication, it doesn't have the same risks for baby as the other methods. The foley catheter also has fewer side effects than prostaglandin gel.
The foley balloon catheter is placed into the vagina and placed behind the cervical wall. It is slowly inflated until the desired outcome is achieved – the hope is that the catheter will stimulate baby's head to encourge the cervix to dilate. Low infection rates have been reported, making it a good option for women requiring an induction, if your hospital offers this option.
Main benefit: low risk induction method.
Main problem: not the most effective option and may require additional methods.
Prostaglandins, which you may know as Prostin in Australia and Cervadil in the US, have been used for cervical ripening since the 1960s. It may be administered via gels, tablet or slow release pessary (inserted into the vagina). All methods are as effective as the other.
If you need to be induced and your cervix is closed (meaning a rupture of membranes or foley catheter is not an option), you may be given prostaglandins to ripen your cervix and establish labour.
A Cochrane Database review on prostaglandin gels found that while prostaglandins increase the likelihood of vaginal birth within 24 hours, they can also overstimulate the uterus, causing the baby's heart to slow. Interestingly, they found it did not increase the c-section rate, and may even reduce it. However, the Cochrane Database advises, “Very limited data were available in the included trials on time in labour and patient satisfaction. Few studies have addressed issues relating to the safety of using vaginal prostaglandins for induction of labour as outpatients”.
Another synthetic prostaglandin cervical ripening drug, misoprostol (Cytotec), is more commonly used in the United States. However, this drug has a dark history of problems with labour induction, specifically with women planning a VBAC. It is not approved by the FDA for uses in labour. The FDA warns:
“There can be serious side effects, including a torn uterus (womb), when misoprostol is used for labor and delivery. A torn uterus may result in severe bleeding, having the uterus removed (hysterectomy), and death of the mother or baby. These side effects are more likely in women who have had previous uterine surgery, a previous Cesarean delivery (C-section), or several previous births.”
Recently, a baby was lost to uterine rupture where a single, low dose of misoprostol was used on a woman with previous c-sections, yet those subitting the information sounded surprised, which is concerning. If you're having an induction, you may like to request a different method or medication.
Main benefit: Simple application of gel; second dose may be required if the first doesn't get things going. Mobility is not as restricted as with synthetic oxytocin.
Main problem: Not as effective as foley catheter; some inductions may fail and cause pain (known as Prostin pains). May not suitable for women with a previous c-section due to increased rupture risk.
Always ask questions when planning your birth – information is power. Never be afraid of getting a second opinion. You need to be your own advocate, do your research, and question everything. If you have enough time before giving birth, look into having the support of a doula, who can help you advocate for your needs and wishes in labour. Either way, you are in control of decision making during your pregnancy and birth – this is called informed consent. It's important for you to understand your rights – see our article on informed consent and what to do if you feel like you can't say no.