Induction of labour: What should I know?

Induction of labour means starting your labour artificially, rather than waiting for labour to start on it’s own.

We consider lots of factors before inducing labour, including how the pregnancy is progressing, your age, medical history, and your own wishes for birth.  Interestingly, our understanding of when to recommend induction has changed  in recent years, due to a number of major scientific studies that were published.

 

inducting labour - dr colin walsh

When might I need an induction of labour?

Induction is recommended in a variety of circumstances, including:

  • Pregnancies complicated by diabetes
  • High blood pressure / pre-eclampsia
  • If the waters have broken but no labour occurs within 24-48 hours
  • There is concern about fetal growth or movements
  • Some maternal medical conditions
  • Even for low risk patients, there is a discussion to be had about the optimal timing of birth.  It’s too big a topic to cover here, but talk to your obstetrician about the latest evidence, including the ARRIVE trial.

 

Does being induced mean I’ll end up having a caesarean section?

This is one of the hot-button topics in obstetrics in recent times!  For many years, we all believed that induction of labour increased the chance of a woman ending up with a caesarean section.

However, over the past decade a number of big studies have been published, showing that in many circumstances women were LESS likely to have a caesarean if they were induced.  There were additional benefits depending on the circumstances, for example less stillbirths, less shoulder dystocia in big babies and better outcomes for mums with pre-eclampsia or high blood pressure.

As you can imagine, this really put the cat amongst the pigeons! It’s the opposite to what people expected and had been told in the past.  We are still gathering evidence on the best timing for birth in a variety of settings.  It’s essential to discuss your individual circumstances with your obstetrician.  But don’t assume that an induction automatically makes you more likely to have a caesarean.  Depending on the circumstances, it may actually increase your chance of a vaginal birth.

 

Does induction of labour carry any risks?

Millions of women have had their labours induced and it is very safe.  However, it does carry a small risk of:

  • Unsuccessful induction: Your cervix doesn’t respond to medication and caesarean section is required.
  • Uterine hyperstimulation: Rarely, a woman’s uterus is very sensitive to the medication, which can make the baby tired.  This is why oxytocin is given through a drip – the drip can be reduced or stopped as needed.
  • Cord prolapse: This serious emergency requires urgent caesarean section but thankfully it’s very rare.  It happens when the cord falls below the baby’s head after the waters break.  Cord prolapse is more common when there is extra fluid (polyhydramnios) or the baby’s head is not well engaged in the pelvis.

 

How do you induce my labour?

We induce your labour by breaking the waters (called “artificial rupture of the membranes”, ARM).  Your obstetrician will use a small plastic instrument to “nick” the bag of waters during a vaginal examination.

The next step is to start a drip containing the hormone oxytocin.  If it’s your first baby, then the hormone drip will start as soon as the waters are broken.

If you’ve had children before, it may be worthwhile waiting 1-2 hours after breaking the waters (sometimes your contractions will commence without the need for oxytocin).

 

What if my cervix isn’t open enough to break my waters?

In order to be able to break the waters, your cervix must be at least 1cm dilated.

If your cervix is closed, we’ll ask you to come in to the birth suite the night before your induction.  The midwife will insert a vaginal pessary or some gel containing prostaglandin overnight.  The pessary works for 6-12 hours.  It helps soften the cervix and open it enough to make the ARM possible.  Occasionally, you’ll need a 2nd dose of prostaglandin.

 

My friend had a “stretch and sweep” of the cervix – what is this?

A “stretch and sweep” is not a formal method of labour induction.  However, it can sometimes help to stimulate natural labour in women who are full term.  It’s more likely to be successful in women who have given birth before.

During a vaginal examination, your obstetrician will gently separate the bag of membranes from the wall of the cervix.  This helps to release some of the body’s own prostaglandins, which can help labour to start.  Most women find the feeling of a stretch and sweep slightly uncomfortable.

 

Is an induction more painful than spontaneous labour?

Some women do find it more painful than spontaneous labour.  This is partly because the medication makes the contractions come on quicker.

We are happy to support the full range of options for pain relief during your induction, including positioning, gas & air, epidural, heat, opioids and TENS.

 

Do natural methods of induction work?

There is no good scientific evidence that sexual intercourse, breast stimulation or hypnosis help induce labour, although they are unlikely to be harmful.

The evidence on castor oil is conflicting but overall it doesn’t appear to be helpful.  It has a lot of side effects, including nausea, diarrhoea and bowel cramps.  Some studies also suggested that castor oil increased the chance of baby passing meconium (the first poo) while still inside the womb, which can lead to serious complications.  Overall, you should avoid castor oil.

Raspberry leaf tea has very limited human data but appeared to have no effect on labour.  In an animal study there was some concern about early onset puberty in female offspring.

There is actually good scientific evidence that acupuncture/acupressure does NOT stimulate labour.  It may have a minor role in softening the cervix, but it has no effect on the need for medication to stimulate contractions, rates of caesarean section, length of labour or need for epidural analgesia. Acupuncture is not a substitute for medical induction.