Like most pregnant women, you'll probably reach a certain point during pregnancy when you’ve had enough.
Enough of being pregnant, uncomfortable, sore and tired.
Enough of waiting to meet the tiny person you’ve been growing for the last nine months.
Even though you don’t really like the idea of having an induction, getting the ‘heavily pregnant’ part over and done with sounds very tempting.
Some women genuinely need to have their labour induced. There are certain situations — for example, pre-eclampsia — where continuing the pregnancy is more of a risk to mother or baby than having an induction.
So if there’s a genuine medical reason why your baby should be born as soon as possible, this article is not for you.
However, these days, labour inductions happen more commonly for convenience rather than for medical reasons. Sometimes it’s simply because a date has passed or a woman’s preferred doctor isn’t available around the due date.
Having an induction of labour isn’t a simple procedure and it's not without risk. It's not about having a bit of medicine and your labour will work just like it would have naturally.
To decide whether or not to have an induction, you need to ask yourself whether being induced is more likely to help or harm you and your baby.
“Inducing labour involves making your body/baby do something it's not yet ready to do. Before agreeing to be induced, be prepared for the entire package, i.e. all the steps. You may be lucky enough to skip one step, but once you start the induction process, you are committed to doing whatever it takes to get the baby out, because by agreeing to induce, you are saying that you or your baby are in danger if the pregnancy continues. An induced labour is not a physiological labour, and you and your baby will be treated as high risk — because you are.” — Doctor Rachel Reed
What Is An Induction Of Labour?
When labour begins on its own (spontaneously), it triggers an amazing and complex process, involving your baby, your body and your brain. Your baby signals when he or she is ready for life outside the uterus and your brain responds to this signal by releasing oxytocin. During labour, this powerful hormone causes your uterus to contract, dilating the cervix and pushing your baby out. As levels of oxytocin rise, your brain releases endorphins – nature’s painkillers.
Induction of labour bypasses these two critical steps in the labour process. Your baby has not given the ‘ready to be born’ signals and so your body can’t respond to those signals with its own hormones.
The last weeks of pregnancy are very important. During this time, your antibodies are passed to your baby, so that the baby is prepared for fighting infection and disease after birth. The baby is also gaining essential fat and iron stores, as well as honing skills like sucking and swallowing. Brain development also accelerates in the last 5 weeks of pregnancy. Most importantly, your baby’s lungs are still developing, and researchers now believe there is a connection between lung development and labour.
In the weeks before labour begins, estrogen levels rise and progesterone levels drop, increasing the uterus’ sensitivity to oxytocin and preparing it for the work to come. Braxton Hicks or ‘pre-labour’ might start the process of thinning and opening the cervix, as well as encouraging your baby to get into the optimal position for birth.
This entire process ensures that labour is effective and your baby is completely ready to be born – able to adjust to life outside the uterus and start a successful breastfeeding relationship with you.
Induction essentially replaces the natural process that happens over weeks, and forces your body to go through it in a few hours. Your cervix is artificially softened and your bloodstream is flooded with synthetic hormones. Contractions are forced to happen quickly and the tempo of labour increases over a short space of time. This makes the pain much harder to manage.
Induction means you are constantly monitored. You will also have an IV drip in place, which restricts movement and your ability to work with the contractions. Induced contractions become much stronger more quickly and are harder to cope with, so there is a greater chance that you will need to request an epidural. You will be checked regularly for fetal distress, as a baby’s heart rate tends to dip in response to the stronger contractions.
Why Is Labour Induced?
The big question is this: Why would a low risk woman agree to be induced if her baby was not in danger? An induction only introduces real risks to what could be a perfectly normal birth. These are the most common reasons for induction:
Post Dates (the ‘due date’ has passed)
Full term is estimated to be between 37 and 42 weeks of pregnancy. Your estimated due date (EDD) falls around the 40 week mark, calculated as 288 days from your last menstrual period. Many hospitals have a policy of induction at 10 days after the EDD. In the US over 44% of women report being induced because they were full term (over 37 weeks) and were near their EDD.
Given that women have individual differences and various factors in their lives that influence their menstrual cycles, it is unreasonable to think babies should be evicted forcefully if they don’t arrive at the ‘right’ time. Research shows that pregnancies can vary in length naturally by 5 weeks.
Babies who are induced before they are ready to be born can miss out on important development in the uterus, and are at greater risk of respiratory problems, low blood sugar, jaundice, irregular heart rate and the inability to stabilise temperature. They are also more likely to have difficulty with establishing breastfeeding, which can have an ongoing impact on health and wellbeing for both mother and baby.
Premature Rupture Of Membranes
When the amniotic sac ruptures before labour begins, it is called premature rupture of membranes (PROM). Many women are given a time frame for contractions to begin naturally (usually 24 hours), and after that they are induced, to avoid the risk of infection.
The results of this study showed women who had experienced PROM and were screened for Group B Strep had very good outcomes when they waited for labour to begin. Induction of labour lowers the risk of infection in the mother, but not in the newborn baby; neither does it reduce the risk of needing a c-section.
Infection after PROM can occur during routine vaginal examinations. Even with sterile gloves on, care providers push bacteria from the vagina up toward the cervix. Avoiding vaginal examinations can reduce the chance of infection in both mother and baby.
Antibiotics are commonly used as a preventative measure, for women whose waters have broken and labour has not begun. What we now know about the importance of bacteria seeding during labour and birth indicates the increased use of antibiotics could be creating future health issues for babies. This review of four studies showed that giving routine antibiotics (where PROM occurred at full term) did not reduce the risk of infection in pregnant women or their babies.
If a woman’s temperature and general wellbeing are monitored, and if antibiotics are available if required, she can be reassured that waiting 2-3 days for labour to begin is a viable option.
Suspected Large Baby
There are many reasons why some babies are larger than others – reasons related to genetics or to underlying health issues, such as gestational diabetes. There’s no way to measure a baby’s size and weight accurately before birth, so babies are only ‘suspected’ to be large until they are born. Ultrasounds are not 100% accurate and there are many reports of women being induced because of a ‘big baby’ when their babies’ birth weight turns out to be average or lower.
The medical term for a big baby is macrosomia. Most guidelines consider babies to be big if they weigh over 4500 grams, or 9lbs 15oz. The main concern with birthing a big baby is the risk of shoulder dystocia, where the baby’s shoulders become stuck. This is regarded as an emergency, with potential for causing injury to the baby (brachial plexus injury). However, this injury occurs about 30% of the time when there is no shoulder dystocia, and can even happen after a c-section.
In cases of gestational diabetes, the evidence recommending induction before 41 weeks to avoid a big baby is weak. The World Health Organisation does not recommend induction for gestational diabetes unless the condition is not controlled or if the placenta is not providing enough nourishment to the baby.
Induction carries risks and there is no evidence to show induction for a suspected big baby improves outcomes; in fact it increases the risk of c-section.
Intrauterine Growth Restriction (IUGR) At Term
The growth of your baby during pregnancy depends on several factors: genes, your health, and how well the placenta is functioning. Some babies are small for their gestational age and others are growth-restricted because they are not receiving enough nourishment via the placenta.
As in the case of a suspected big baby, it is only possible to tell whether a baby is small genetically or because of a medical problem when the baby has been born. A diagnosis of IUGR relies on accurate dating in early pregnancy. As mentioned earlier, not all women have exactly the same menstrual cycle and many women are not aware of when they conceived, making their EDD a guessed date rather than an exact one. Ultrasounds during pregnancy are more accurate before 20 weeks, when the margin of error is 7-10 days. Ultrasound dating at or near term is more likely to have a margin of error of 3 weeks.
A study from the Netherlands shows that waiting for labour to begin spontaneously (expectant management) has the same outcomes as induction for babies suspected of IUGR. The results show that significantly more babies in the induction group were admitted to high or medium-level NICU care. The babies in the expectant management group, who were born when they were ready, were about 100 grams heavier than the babies in the induction group.
During pregnancy, your baby is surrounded by a sac filled with liquid called amniotic fluid. It protects your baby and the umbilical cord from trauma and infection.
Amniotic fluid is produced by the mother, absorbed by the baby from the placenta, and then excreted via the baby’s lung secretions and urine output. After 2o weeks of pregnancy, fetal urine is the primary source of fluid. The levels fluctuate, depending on how hydrated the mother is, how much the baby swallows and urinates, and whether the baby has problems with kidney function.
In some cases, amniotic fluid levels might be too low (oligohydramnios). The amount of fluid can be measured using two methods:
- Amniotic fluid index (AFI) evaluation: four ‘pockets’ of fluid are measured by ultrasound and added up, resulting in an Amniotic Fluid Index (AFI)
- Deep pocket measurements: the single deepest vertical pocket of fluid is identified by ultrasound and measured in centimetres
If the AFI shows a fluid level of less than 5 centimetres, the absence of a fluid pocket 2-3 cm in depth, or a fluid volume of less than 500mL at 32-36 weeks gestation, then oligohydramnios is suspected. There is no current standard as to what is considered high or low amniotic fluid, and most cases are isolated – meaning there is no underlying issue causing the fluid levels to decrease.
About 4% of women are diagnosed with oligohydramnios. Low risk women at term (37-42 weeks) with a suspected diagnosis of oligohydramnios can either wait for labour (with monitoring) or be induced. The vast majority of doctors will push for induction over expectant management. This is despite the evidence showing labour induction does not improve outcomes for babies but increases the risk of interventions and c-section.
How Is Labour Induced?
There are three main steps to labour induction and you might need some or all of them.
Your doctor might not tell you about some risks listed in this section, and you might find them worrying or disturbing. However, if you were given a packet of the drugs used for induction, this is the information you would have to be given about their use and effects. It’s not intended to frighten you, but to help you make a balanced, informed decision based on the risks and benefits. When it’s a question of life-saving benefits, of course, there is no risk you wouldn’t take. But if your or your baby’s life is not in danger, it’s worth considering whether induction is worth the risks to you and your baby.
#1: Cervix Assessment / Stretch and Sweep
Your doctor or midwife will do an examination to determine if your cervix is favourable (slightly open or dilated) or unfavourable (firm and closed).
If your cervix is favourable, a stretch and sweep of the membranes might be offered as a ‘drug-free’ option. A stretch and sweep might be painful, depending on the practitioner, but it can be uncomfortable and result in some bleeding afterwards.
To sweep the membranes, the care provider places a finger inside your cervix and separates the membranes from your cervix, stretching the cervix at the same time. Even though your care provider will be using sterile gloves, inserting anything into the vagina has the potential to push bacteria up to the cervix.
You might be given the option of having your waters broken straight away if your cervix is favourable (see below).
If your cervix is not favourable, the next step is to use artificial prostaglandins to soften and open your cervix. This drug is inserted, either as a gel or a pessary, into your vagina close to the cervix. The drug acts to soften and dilate the cervix and stimulate contractions. Prostaglandins can take several doses to work, so you might need to return to hospital several times.
Prostaglandins can cause hyperstimulation of the uterus (excessively strong contractions) resulting in fetal distress and c-section.
If the prostaglandin use is effective and your cervix opens slightly, your waters can be broken (see below) to further encourage labour to begin.
#2: Artificial Rupture of Membranes (ARM)
If your cervix is favourable and your baby is head down and well engaged, you might be given the ‘drug free’ option of having your waters broken. A special hook is inserted through the cervix to create a hole in the amniotic sac, allowing the amniotic fluid to leak.
This is done in the hope that labour will begin but there’s usually a strict time limit on how long you can wait for contractions to become established. Usually it’s only an hour or two before another method of induction is used.
The risk of infection is increased with ARM – because something is being inserted into the vagina and moved upwards towards the cervix. There is also the possibility of fetal distress and c-section. The amniotic fluid protects your baby, the placenta and the umbilical cord from the pressure of contractions during labour. If your waters have been broken, there is less cushioning in the uterus. Sometimes the cord can be compressed and reduce baby’s heart rate. This isn’t always a problem but some babies don’t cope well and show signs of distress, meaning a c-section becomes more likely.
In rare cases, the baby turns into the breech position, and this can be problematic if the membranes have ruptured and the baby’s head isn’t engaged. There is also a risk of cord prolapse, which occurs when the umbilical cord slips out before the baby.
#3: Synthetic Oxytocin (Pitocin, Syntocinon)
In a natural labour, the bloodstream is flooded with oxytocin, a hormone that stimulates the uterus to contract. As contractions intensify and last longer, your brain releases endorphins – natural painkillers. As the endorphin levels increase, so do the oxytocin levels and the tempo of labour increases. Nature has created a perfect dance of hormones that encourage efficient contractions and a productive labour.
Artificial oxytocin does not cross the blood-brain barrier and acts only on the muscle of the uterus. It’s administered through an intravenous drip and might be used after the above steps, or before, or during labour to speed things up (augmentation), if you are not progressing as well as your care provider would like.
Artificial oxytocin is started at a low dose that is increased until your contractions establish a pattern and consistency – the required number of contractions per hour. Most women report these contractions as very painful and difficult to cope with, especially as monitoring is required and movement is restricted. It’s not uncommon for women to request pain relief and experience further interventions when being induced with artificial oxytocin.
Side effects of Pitocin/Syntocinon include:
- Hypotension (low blood pressure)
- Postpartum haemorrhage
- Water intoxication
- Hypertonic uterus
- Uterine rupture
- Uterine inversion
- Abnormal heart rates
- Nausea and vomiting
Babies born to mothers who have been induced with oxytocin can have reactions such as irregular or abnormal heart rates, retinal haemorrhage, jaundice, brain damage and death.
Every woman’s situation is unique to her own health and the wellbeing of her baby. In order to decide between induction and waiting for labour to begin spontaneously, women need to be provided with the benefits and risks of both options.
Before choosing to be induced, you need to be aware that in most cases you can’t change your mind after the process has begun, especially in the case of artificial rupture of membranes. In the majority of situations, after an induction has begun, you will need to do whatever is needed for your baby to be born. Unless there is a clear risk in continuing with your pregnancy, induction should be an absolute last resort.
Get Informed About Induction
An induction of labour triggers what is known as ‘the cascade of interventions'. What does that mean? The clip below is a snippet from the documentary, The Business of Being Born — essential viewing for anyone having a baby. If you don't have time to purchase the DVD, you can watch the documentary via live streaming.
Finally, watch this clip from the late Marsden Wagner. Marsden was a Director of Maternal and Child Health for the World Health Organization.