Induction and Augmentation of Labour
Most women start labour naturally. However, there are some specific reasons for which your healthcare provider may recommend assistance to either start labour or strengthen your contractions during labour. Starting labour is called induction and strengthening labour is called augmentation. It is important to have a conversation with your healthcare provider about the risks and benefits of these procedures, the potential impact on breastfeeding, and their practice preferences before going into labour. This will help you to make an informed decision about your care.
- Pregnancy related hypertension (higher than 140/90) beyond 38 weeks
- Pre-eclampsia beyond 37 weeks
- Severe maternal illness
- Poorly controlled diabetes
- Poor growth of the baby (growth restricted)
- Term rupture of membranes and no labour, or when the mother has Group B Streptococcus
These are not all of the possible reasons, but they are the most common.
The following are population level benefits and risks. In order to make an informed decision, it's important to speak with your healthcare provider to discuss how these may apply to your individual situation. "Induction should never be used for the convenience of the mother or the health care provider."1
If the risks, at any time, of continuing your pregnancy for either you or your baby are higher than having the baby, induction of labour (starting labour) is a procedure that can be life-saving.
When labour is not progressing, augmentation can assist labour to progress and reduce your risk of a caesarean birth.
The use of synthetic oxytocin during labour and birth may carry some risks that we are just learning about. Naturally occurring oxytocin hormone levels are normally at their highest levels immediately prior to and right after birth.9 To learn more about how the use of synthetic oxytocin may interfere with your natural hormonal feedback and release of natural oxytocin from your brain, please read Dr. Sarah Buckley's blog: Synthetic Oxytocin (Pitocin, Syntocinon): Unpacking the myths and side-effects. These effects may lead to:
- Lowered calming and pain-relieving effects for mother during labour2
- Increased risk of postpartum hemorrhage (excessive bleeding)2 [REF-4s9]
- Need for more/increased synthetic oxytocin for labour to progress2
- Prolonged pushing stage2
- Increased use of vacuum or forceps at birth2 [REF-4s9]
- Disruption/difficulty with newborn breastfeeding and bonding/attachment (oxytocin & prolactin hormones interference)2
- Potential short and long-term effects on infants2
- There is a risk of caesarean birth if your labour does not progress or your baby doesn't tolerate the induced labour (fetal distress).1 [REF-4s9]
- Excessive uterine activity (contractions too close together)[REF-4s9]
- Bacterial infection of the uterus1 [REF-4s9]
- Umbilical cord prolapse (cord dropping down through the cervix)1 [REF-4s9]
- Birth of a preterm baby when dating was inaccurate1 [REF-4s9]
- Uterine rupture (tearing open)1 [REF-4s9]
Natural options to prepare your cervix &/or start labour
You can learn more about the evidence, benefits and risks for these options at the Evidence Based Birth Natural Labour Induction Series.
Be sure to discuss use of any of these options with your healthcare provider prior to using them.
It's important to discuss the N (Not Now) in the informed decision-making acronym, BRAIN (Benefits, Risks, Alternatives, Intuition, No or Not Now).
When weighing the benefits and risks of induction or augmentation procedures, ask the question: What if I wait a little longer?
- Induction: This is particularly important if your cervix has not begun to prepare for labour yet. Ask your healthcare provider about your Bishop's Score. This will help you understand the likelihood of induction success. Weigh your risks and benefits of doing the induction now or waiting a few days or a week. Waiting may improve the possibility of induction success or going into labour on your own without increasing risk. The healthiest choice most of the time is to let labour begin on its own.
- Augmentation: Labour may slow for several reasons but stress, anxiety and fatigue can have a big impact. There are some things that you can try first to help your labour begin to progress again before going to medical augmentation:
- The environment you labour in and the support you receive during your labour plays a big part in optimizing your labour hormones. Having trusted labour support &/or a Doula and creating a safe, dark, calm, quiet, loving and respectful environment can help you relax and allow your body's natural hormonal physiology to make your labour more efficient and effective.
- Staying upright and changing positions or labouring in a deep tub can help your baby move into a better position for birth. Position changes and movement help in the same way wiggling a ring off a swollen finger does. Moving your pelvic bones around your baby's head can help to wiggle the baby through your pelvis.
If an induction is recommended for:
- Prolonged pregnancy, it's important to learn more about what this means. Rachel Reed describes this well in her post about Post-Dates Induction of Labour: balancing the risks.
- A big baby, it's important to learn more about what this means. Rebecca Dekker describes this well in her post about Evidence on: Induction or C-section for a Big Baby? The following evidence should be discussed with your Healthcare Provider:
- Prenatal prediction of a big baby based on an ultrasound or physical exam will be wrong about half the time 3
- "Ultrasound weight results at the end of pregnancy can fall anywhere from 15% above or below the baby’s actual weight."3
- "The suspicion of a big baby leads many care providers to manage a woman’s care in a way that increases the risk of Cesarean and complications."3
There are various methods for induction.
Ripening (softening) of your cervix:
Before labour begins the cervix makes some physiological changes to be ready to respond to the contractions. It lines up with the vagina, softens, thins and starts to open.[REF-4s9] If your healthcare provider has assessed that your cervix has not begun its preparation for labour yet, you will be asked to come into the hospital the evening before your induction for a procedure that will enhance the effectiveness of your induction. The following options: Foley Catheter and Prostaglandins, both ripen (soften) and prepare your cervix for labour and may start labour contractions. Your healthcare provider will have a discussion with you to decide which will be the best option for you.
A soft rubber catheter (tube) with an inflatable balloon at the end is placed through your cervix and then the balloon is filled with sterile water and pulled back against the cervix.[REF-4s9] The end that extends out of your vagina is taped to your thigh.[REF-4s9] It is left in place until it falls out on its own (usually overnight) or after 24 hours.[REF-4s9] This method stretches the cervix and causes the release of naturally occurring prostaglandins.[REF-4s9] The procedure is performed the evening before your induction. You will experience some cramping after the procedure. Your baby will be monitored with an external fetal heart rate monitor for at least one hour after insertion to make sure they are coping with the procedure. You will then be sent home with instructions for when to return to the hospital. The benefits of this procedure is that it is a simple procedure and has less risk of side effects such as excessive contractions.[REF-4s9]
Synthetic versions of naturally occurring chemicals, prostaglandins, are applied by gel or a tampon-like device to your cervix. Prostaglandins will not be used if you have had a previous caesarean birth. You will experience some cramping as the prostaglandins begin to work. Your baby will be monitored, with an external fetal heart rate monitor, for at least one hour after insertion to make sure they are coping with the procedure. You may need more than one dose.4 If additional doses are needed, they will be given every 6 hours.4 You will then be sent home with instructions for when to return to the hospital.
Return to hospital if:
- your contractions become very frequent (more than four contractions occur in a 10-minute period)[REF-4s9]
- your contractions become very long (i.e., last longer than 60 seconds)[REF-4s9]
- your contractions become very painful[REF-4s9]
- your water breaks[REF-4s9]
- you have bright red vaginal bleeding[REF-4s9]
- you are not feeling the baby move
- you are unable to manage your contractions at home
- the Foley catheter comes out[REF-4s9]
- there is any other reason you feel you need to return to the hospital[REF-4s9]
If you go home and labour doesn’t begin by the following morning, or within 12 hours after insertion, a nurse will call you to plan the time of your return. You should eat light meals and drink plenty of fluids while at home. Once you come back to the hospital, your healthcare provider will discuss with you the next steps.
These may include one or more of the following options.
Sweeping of the Membranes
Sweeping, or stripping, the amniotic membranes is a simple intervention, that can be a first step to try to start your labour. The process of separating the amniotic membrane from the uterus can stimulate the production of prostaglandins. This may trigger contractions and labour in 1 out of 8 women.5 Studies have shown that it can also reduce the length of your pregnancy on average 4 days6 and may avoid the need for induction for post-dates.
If your cervix is open a little, this step can be done in your healthcare provider's office. "To sweep the membranes, your healthcare provider reaches a gloved finger through the cervix. They then 'sweep' their finger around the inside edge of the opening."5 Many women find the procedure quite painful6 and it may make you feel uncomfortable for a period of time afterward. You may have some bleeding and irregular contractions. There is also a 1 in 10 chance of your membranes rupturing during the procedure.6
It's important to be aware that some healthcare providers consider membrane sweeping part of their routine care. Since it is an intervention, it's important to discuss membrane sweeping with them before the end of your pregnancy so that you can make an informed decision if this procedure is best for you.
Artificial Rupture of your Membranes (ARM or "breaking your water")
If your cervix has started to dilate, the membranes (the sac surrounding the amniotic fluid around your baby) are ruptured using a long plastic tool with a tiny plastic hook on its end used to nick the amniotic sac and the water is released.[REF-4s9] This will feel like a vaginal exam. The baby must be well engaged in your pelvis to perform this procedure to avoid the risk of a cord prolapse (umbilical cord falling through the vagina ahead of the baby).[REF-4s9] Rupturing your membranes may start labour or cause your labour contractions to become more intense and your cervix to dilate.[REF-4s9] You will be encouraged to go for walks around the hospital to wait for/assist labour to begin on its own. If your contractions do not start after rupturing your membranes, then your healthcare provider will discuss the use of synthetic oxytocin to help your contractions to begin. Once your membranes have been ruptured, you and your baby become more vulnerable to infection. One important way to reduce the risk of infection once your membranes are ruptured is to minimize the number of vaginal exams during labour.7
Synthetic Oxytocin (synthetic hormone)
An artificial form of the naturally occurring hormone oxytocin is mixed with a saline solution and given by an intravenous (IV) infusion.[REF-4s9] This medication will cause your uterus to contract. The dosage is precisely controlled with an infusion pump so that your contractions occur every 2-3 minutes, lasting 60 seconds, at a moderate to strong intensity. The baby’s heart rate will be continuously monitored when Oxytocin is used to ensure the baby can tolerate the increase in frequency and strength of contractions.[REF-4s9] Labours started with synthetic oxytocin start much more quickly with more intense contractions. In addition, the limitations on your movement and ability to change positions and access comfort measures such as warm water (shower or bath) reduces your ability to work with the pain of contractions. This may increase the need for medical pain management such as an epidural.[REF-4s9]
Uninterrupted skin to skin with your baby immediately after birth, until after the first breastfeeding (1-2 hours) and regularly into the postpartum period, would be of benefit if you require synthetic oxytocin in labour and birth. This is because skin to skin contact increases your production of naturally occurring oxytocin.
Augmentation of Labour
Augmentation of labour may be required if you are in labour and are already having contractions, but your labour is not progressing towards the birth of your baby (i.e., your cervix dilating and the baby descending in your pelvis).
The primary reasons for prolonged labour may be related to one of the following:[REF-4s9]
- the power of the contractions (strength, length, frequency)
- the passenger (the baby's position & size in relationship with the pelvis)
- the passageway (maternal pelvis size and shape in relationship with the baby)
- maternal psyche (your anxiety &/or pain perception and resources to manage it).
Identification of the specific reason causing the delay and steps to correct it, may allow labour to move forward.[REF-4s9] See the Alternatives section for non-medical ways to help your labour progress if it has slowed.
Medical augmentation may be done with one or both of the following two methods. Both of these procedures are described above in the Induction of Labour section.
Artificial rupture of your membranes
- This method is the same process used for induction of labour. It may speed up your labour since the baby’s head is pressing harder against the cervix. Once the cushion of water is gone, stronger contractions may follow.
Oxytocin (synthetic hormone)
- Used to increase the strength and frequency of your contractions if your labour has slowed. This method is the same process used for induction of labour.
If you have specific questions
- Speak with your healthcare provider
- If you are giving birth at LHSC, speak with the nurse at the London Health Sciences Centre (LHSC) Preadmission Clinic. A pamphlet is available at the LHSC Women’s Health Clinic for more information on induction and augmentation of labour.
Last modified on: October 22, 2019
- PCMCH: Oxytocin to Help Start or Speed Up Your Labour
- Synthetic Oxytocin (Pitocin, Syntocinon): Unpacking the myths and side-effects
- Post-Dates Induction of Labour: balancing risks
- LHSC Induction
- Childbirth Connection: Labor Induction Basics
- Lamaze: Induction with Pitocin (Synthetic Oxytocin)
- Lamaze: Artificial Rupture of Membranes
- Evidence Based Birth: The Evidence on Membrane Sweeping