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Induction of Labour

What is Induction of Labour?

Induction of Labour is where a woman becomes overdue in her pregnancy which indicates artificially starting labour using pharmacological methods. Every hospital or birthing unit varies at what sort of drugs they use to induce labour but this article is to explain the process and the reasons why they are done.

Induction of Labour for pregnancies that are overdue or for medical reasons

Why Induce Labour?

Labour is normally induced when a pregnancy becomes prolonged and the woman becomes overdue. Induction of Labour is normally done from 1 week to 2 weeks overdue.

There are various reasons why a Labour would be Induced

  • For post Dates pregnancy
  • For some Diabetes
  • Pre Eclampsia
  • Pre Term, pre labour rupture of the membranes (waters broken early)
  • Pre-labour rupture of the membranes in a term pregnancy
  • For a Larger than normal baby
  • Persistent reduction in Fetal Movements

Methods of Inducing Labour

There are various ways of inducing labour, this article will discuss the pharmacological ways of inducing labour in the order that they would occur and the reasons for it.

Membrane Sweep

What is a Membrane sweep?

This sounds very strange but the bag of waters your baby is in are called the membranes. This is a balloon like bag full of amniotic fluid that surrounds your baby.

The Cervix is the opening from your womb (uterus), that leads to the vagina. It is a tubular like structure which holds the pregnancy in for the full 40 weeks. Near the end of your pregnancy or nearer to when you start labour the consistency of the cervix becomes shorter and softer and there is a plug of mucous within the cervix which protects the pregnancy from any bacteria, you may have heard it being referred to as a "show", this occurs when there are any changes of the cervix.

If you have been asked by your midwife if she can do a membrane sweep then she will perform an internal examination, and with her finger she will be able to insert it into the cervix - (if it is soft enough and slightly open) she will then take her finger around the cervix to detach the cervix away from the membranes thus giving you a membrane sweep! This may also detach the mucous plug away from the cervix itself.

The action of this is to release the hormone oxytocin from your body which causes contractions to start, therefore inducing your Labour.

Indution of Labour - Diagramatical representation of How a Prostaglandin Gel is administered.

Indution of Labour - Diagramatical representation of How a Prostaglandin Gel is administered.

Artificial Hormones - Prostaglandins

Prostaglandins are used if the membrane sweeps did not work and are administered by a midwife or a doctor. There are various different types used by hospitals but mostly come in a vaginal pessary or gel .

Pessaries and gels are administered by a midwife or Obstetrician when performing an internal examination. They come in different dosages depending on whether it is your first or subsequent pregnancy. The pessary or gel is placed near the cervix, This dissolves and releases the hormone Oxytocin which can trigger off labour.

A cycle of induction usually takes 2 doses of the prostaglandin to work, given at least 6 hours apart. A Third dose maybe required at the discretion of the obstetrician.

The whole point of inducing labour in this way is to soften the cervix so that it becomes slightly open enough and near enough for the midwife or doctor to break your waters.

In some cases the prostaglandins work very well and can put women into established labour, others may need a couple of cycles to soften the cervix.

Induction of Labour - an amnihook is used to break your waters.

Induction of Labour - an amnihook is used to break your waters.

Artificial Rupture of the Membranes (or ARM)

This is when the midwife or doctor will break your waters for you, the action of doing this stimulates the production of the hormone oxytocin which causes contractions to start.

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It also helps to bring the baby's head down onto the cervix which also helps to stimulate contractions.

In order for the doctor of midwife to break your waters, the cervix needs to be open slightly and soft and easy to reach.

It is done using a plastic instrument called an amni-hook which looks like a crochet hook.

This process can be done to either try to accelerate your labour that has started and there has been no progress over a period of time or to start off labour if there have been no contractions.

After breaking your waters the medical staff will possibly leave you to mobilise for a couple of hours until contractions start.

If contractions do not start of they are very mild then there is a likely hood that you are accelerated in labour using a drip called oxytocin.

Induction of Labour - A drip may need to be used to accelerate your labour.

Induction of Labour - A drip may need to be used to accelerate your labour.

Induction of Labour - The Oxytocin Drip

The Oxytocin drip is a synthetic hormone that is infused very slowly through a drip to create contractions and therefore speeding up your labour. The hormone acts directly upon the Uterus stimulating the uterine muscles to contract and therefore accelerating your labour.

This can only be done if your waters have broken or else it will not work at all

A cannula would be needed in your hand to set up the drip

The midwife would need to monitor your baby using a CTG Machine that record the fetal heart rate against contractions you are having as they would need to assess the wellbeing of your baby and how well it reacts to the contractions you will have.

The midwife will also asses how many contractions you are having in 10 minutes as the rate of the oxytocin drip goes up every 30 minutes until you are having 4-5 contractions in 10 minutes.

Disadvantages of Induction of Labour

  • Inducing labour would need to be for a valid clinical reason, however there are some drawbacks such as
  • increase risk of having stronger analgesia such as epidural
  • increase risk of instrumental delivery by 15%
  • increase risk of mal-position of the baby
  • Increased risk of Caesarean Section by 22%

Induction of Labour video explained

  • Top 10 items you need for Labour and Birth
    This list gives you an idea on what to pack in your maternity bag when you have your baby. You don't really need hoards of items with you.
  • The Use of Water for Labour and Birth
    Waterbirth and using water for pain reliver in Labour can benefit many women as well as having a calmer experience having your baby in water is also becoming increasingly more popular.
  • Pethidine in Labour
    Using pethidine in labour is down to personal choices and also how you wish to manage your labour and delivery, but don't rule it out of your plans as some women can cope perfectly well without further drugs and there are situations when pethidine in
  • The use of Gas and Air in Labour
    What is Gas and Air? Gas and air is a mixture of Nitrous Oxide and Oxygen, it is also known as Entonox. It is safe to use in labour but Gas and air does have some side effects as below.
  • The mechanism of Second and Third stages of labour
    What ids the second stage of labour? What does it feel like? How is the placenta delivered and when? Read this useful article and find out.
  • Stages of Labour - Latent and first stage of Labour.
    What are the stages of labour and how do you know when you are in Labour? How can you cope with the early stages of labour - read this article and find out!
  • Best Birthing Positions for Labour
    What is the best birthing position to be in labour? How can you bring on you labour or even speed it up? Years ago women were told to deliver on the bed in the hospital, this is no longer the case as more and more women are becoming more active with


Jo Alexis-Hagues from Lincolnshire, U.K on November 19, 2014:

This is excellent information! Useful, well written and presented. There's a need for articles like this, ideal for mums to be, students and those who simply want to learn more about this process.

Well done.

babynology from New York on July 05, 2013:

I have something interesting.

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