Induction of labour is when your care provider uses an artificial method to start labour.
Induction does carry significant risks to mother and baby, and should only be recommended if it’s safer for your baby to be born as soon as possible.
Once a medical induction has been started, in most cases, you're then committed to doing whatever it takes to ensure your baby is born.
For the majority of women, once an induction has begun, birth must occur. This may mean assisted birth (episiotomy, forceps etc) or even a c-section. It’s important to be fully informed of the risks and benefits of each induction method.
You might like to discuss with your doctor the possibilities of beginning with the more gentle methods of induction, in order to allow your body time to adjust. It’s still possible to have a positive birth experience with an induction.
Why Am I Being Induced?
Induction of labour should only be indicated if there are risks or complications that can compromise the health of you or your baby. Here are the main medical reasons to induce:
- The placenta is separating from the uterus (placental abruption)
- Infection in the uterus
- High blood pressure (preeclampsia)
- Maternal health problems, such as uncontrolled diabetes, heart disease, certain autoimmune disorders
- Baby has a growth or health problem
- Amniotic fluid levels are too high or too low
Sometimes doctors will recommend induction for reasons that are not due to disease or complications, but because a risk factor has occurred. These reasons may include:
- Ruptured membranes before labour, which may increase the risk of infection
- Pregnancy is past 41 weeks, which slightly increases the risk of stillbirth or neonatal death
- Suspected big baby, which may increase the risk of obstructed labour or injury to the baby
These risk factors are not medical problems but have the potential to be complications. In most cases you will be offered an induction to lower the risk of complications occurring. It’s important you’re fully informed about your options before deciding to induce, as the best evidence doesn’t always support induction for these risk factors.
Non-medical reasons for induction are unfortunately becoming more common and aren’t related to the health of you or your baby. These reasons usually relate to convenience for either the care provider or the mother and actually increase the risk for both mother and baby.
How Long Does Induction Of Labour Take?
It's natural to wonder how long an induction of labour will take. However, it’s impossible to predict how long any one induction will take to start labour, or how long labour will be once it has begun.
The length of time it takes for labour to start and then progress depends on how your body responds to the methods used. Usually women who have experienced spontaneous labour before will find their bodies respond more effectively than first time mothers or those women who have not previously experienced spontaneous labour.
If your cervix is unripe (hard, long and closed) it might take 1-2 days before induction methods are effective. If your body happens to be ready for labour and just needs a small push. In that case it may be a matter of hours before you give birth.
Some doctors might use your Bishop score (based on cervical dilation and effacement, and baby’s station) as a guide for choosing an induction method.
Most often a combination of induction methods are used. However it’s worth discussing with your doctor if you can begin with the less invasive methods first, if time is not a factor.
Stretch and Sweep
If your cervix is favourable (soft and stretchy or slightly dilated) a stretch and sweep may be an option. Your doctor or midwife will put a gloved finger through your cervix and separate the sac from the uterus near your baby’s head. They may also physically stretch the cervix.
This method of induction is not always successful. If labour starts it will usually be within 48 hours. Sometimes several attempts are needed.
Your cervix will start to thin or ripen at the beginning of early labour. If you’re being induced and your cervix hasn’t begun this process, synthetic prostaglandins can be used. This can be inserted as a gel or suppository.
If prostaglandin gel is used, you may need one or more doses which may be given every six to eight hours. The suppository slowly releases the prostaglandin over 12 to 24 hours. It’s estimated prostaglandins work for about 90% of women.
Most often another method of induction is used once your cervix is soft and open. This is usually synthetic oxytocin or artificial rupture of membranes.
Syntocinon or Pictocin are synthetic forms of the hormone oxytocin, which your body produces to stimulate contractions. Synthetic oxytocin is used when a membrane sweep or prostaglandin hasn’t started labour.
Synthetic oxytocin is given through an intravenous drip (IV). How quickly your body responds depends on how ready both your body and your baby are for labour. In most cases the drip will be started on the lowest dose and increased regularly until contractions are regular (roughly 3-5 contractions every ten minutes).
Many women will need 6-12 hours of synthetic oxytocin to enter active labour, when the cervix is dilating 1cm per hour. Once active labour begins, you may have your waters broken as well to speed things along.
Artificial Rupture Of Membranes (AROM)
Britain’s National Institute for Health and Care Excellence (NICE) guideline on induction doesn’t recommend AROM to be used as a first method or with synthetic oxytocin. It’s more likely to be used as a method to speed or augment labour once other methods of induction have been used.
Cervical Balloon (Also Known As A Foley Balloon)
This is a small flexible balloon catheter that is inserted into your cervix then filled with saline solution, which will dilate your cervix mechanically.
A cervical balloon is sometimes tried in place of a prostaglandin gel to help an unripe cervix become soft and open. One advantage of the balloon is there’s significantly fewer cases of uterine hyper stimulation when compared to prostaglandin gel. However, the use of synthetic oxytocin is higher in women beginning an induction with a cervical balloon instead of prostaglandin gel.
The balloon can be kept in for 24 hours, but may fall out if your cervix has dilated before then. There is no guarantee contractions will begin and other induction methods are likely to be used.
If you need to be induced for medical reasons, it can be a nerve wracking and stressful time. Being informed about your options and the process of induction can help you to feel in control and make decisions that are best for your situation. Having a dedicated support person can help you cope and focus.