Stages of vaginal delivery

It is joyful for expectant women to leave hospital holding their newborns after successful delivery. Photo/FILE 

By Louise Abbott, Bupa Health Information Team,

Vaginal birth is the usual way for your baby to be born. The process of giving birth to your baby is known as labour. There are three stages to labour that will last for different lengths of time.

Pain relief helps to manage your pain during labour. Availability and use of different treatments may vary from country to country. Ask your midwife or doctor for advice on your treatment options.

Most women are healthy and have a straightforward pregnancy and labour.

There are three stages that you will go through when you give birth vaginally. Labour varies according to a number of factors, such as whether or not it's your first pregnancy, the size of your baby and his or her position in your uterus (womb).

First stage

Before active labour starts, your body goes through some changes in preparation, so it's not always easy to tell exactly when labour has started.

When your baby is ready to be born, the balance of hormones (chemicals found naturally in your body) changes and makes your cervix (the neck of your womb) become softer and shorter.

You may also have what is called a show. This is when the plug of mucus that acts as a seal in your cervix during pregnancy falls out as your cervix changes shape. This may happen any time between several days and a few hours before labour starts.

Hormones also cause you to have contractions. The muscles in your womb tense and relax so that your cervix stretches and opens (dilates). Contractions feel like a wave. They start gently and gradually build, becoming intense and then easing off.

It may take some time for the contractions to become regular but they will gradually get stronger and closer together.

The first stage of labour is often defined in two periods – the latent first stage and the established first stage. In the latent first stage, you will have painful contractions and your cervix will dilate up to 4cm. In the established first stage, you will have more regular, painful contractions and your cervix will continue to dilate from 4cm up to 10cm.

At first you may only have a contraction every 15 to 30 minutes. After a while, they will be more frequent and stronger, occurring every two to three minutes. The length of time that each contraction lasts is usually between 10 and 40 seconds, but this will be different for every woman.

When you have a contraction, you will feel a build-up of tension across your abdomen (tummy), pain in your back and possibly also between your thighs and low down in your pelvis. You may also find that your waters break.

This is a normal part of labour and is when the bag of fluid that surrounds your baby breaks as your cervix widens. It's also referred to as your membranes rupturing. The fluid may rush out in one go or in a steady leak.

Your waters can break at any time during labour. However, if your waters break when you're not in labour and labour doesn't start within the next few hours you should contact your midwife or doctor for advice on what to do next.

At 10cm, your cervix is fully dilated allowing your baby to move lower through your pelvis. For women having their first baby, labour lasts on average for about 8 hours, most of which is the first stage of labour.

Labour is unlikely to last for longer than 18 hours. It's likely to take less time if it's not your first baby, because your pelvis and vagina have been stretched before.

Second stage

The second stage of labour is when you give birth to your baby. It usually lasts about one to two hours.

As your baby's head gets lower, you will eventually feel a strong urge to push and this helps your baby to be born. This is a unique feeling which your body does of its own accord. You will still be having contractions to help you push, though they may be less frequent but longer. You may feel more comfortable if you are upright, kneeling, sitting or squatting.

As you push, your baby moves further down through your pelvis until his or her head stays at the entrance to your vagina between contractions. This is called 'crowning' and means your baby is about to be born. Usually, your baby’s head is born first, followed by the shoulders and the rest of the body.

Third stage

This is when the placenta and membranes that held your baby in the womb are passed out of your body. You can let this happen naturally or you can be given a medicine to help the process.

Active management of the third stage by your midwife or doctor

Your midwife or doctor may be able to help the third stage to progress more quickly and safely.

As your baby's shoulders are being born, you may be given an injection of a hormone called oxytocin, or a combination of oxytocin and a medicine called ergometrine. Within about two minutes, these cause your womb to contract strongly to help reduce serious bleeding.

The umbilical cord is clamped and cut about two to three minutes after your baby is born. The midwife or doctor will then deliver the placenta by pulling gently with one hand on the part of the umbilical cord that is still attached to it.

This takes up to 30 minutes. Research has shown that this method reduces your risk of serious bleeding. However, it's possible that you will have some side-effects as a result of the medicines. These can include headache and feeling sick or vomiting if you were given an injection of ergometrine.

Natural (physiological) management of the third stage

You may choose for the placenta to be delivered without any medicines. After your baby is born, you will be encouraged to cuddle him or her and try breastfeeding. This causes hormones to be released which help your womb to contract and push out the placenta. The umbilical cord isn't clamped and cut until the placenta has been delivered. This can take anything from a few minutes to about an hour.

There are a number of reasons why this type of third stage may not be possible, including if:

• you had an epidural or pain-relieving medicines during labour

• you have had a long labour

• you had heavy bleeding during this pregnancy or with a previous birth

• there were problems during labour or if you had an assisted delivery

Complications of childbirth

Complications are when problems occur during or after a vaginal delivery. Sometimes labour doesn't go as planned and you may need help for your baby to be born safely.

Induction of labour

Induction is when you are helped to go into labour. There are a number of reasons why this may be suggested, including if:

• there is a problem with you or your baby and you need to give birth to your baby early

• your pregnancy is overdue

• your waters have broken, but labour hasn't started

There are several methods that can be used to induce labour. Membrane sweeping is when your midwife or doctor puts their finger inside your cervix and makes a circular movement.

This separates the membranes around the baby from your womb and releases hormones, which can start your labour. If this doesn't happen, there are a number of other ways that your labour can be started. These are explained below.

• Prostaglandins. This is the way that most women will have their labour induced. Prostaglandins are hormones that are usually produced by your body to trigger the beginning of labour. They stimulate your cervix to get softer and shorter.

You will have either tablets or a gel placed into your vagina.

• Rupture of membranes. This is when you artificially have your waters broken. It's done using a special plastic probe. Rupturing your membranes causes hormones to be released that can start your labour.

• Oxytocin. This causes your womb to contract. You will receive it through a drip inserted into your arm. Oxytocin is usually given if your membranes have already ruptured.

Having labour induced can be more painful than going into labour naturally. Talk to your midwife or doctor about pain relief during your labour.

Acceleration of labour

This is sometimes called augmentation of labour. If labour is taking a long time and isn't progressing at the rate that would usually be expected, you may be offered treatment to speed up the dilation of your cervix and strengthen your contractions.

You may be given oxytocin through a drip to help your womb contract more strongly. If your waters haven't broken, then your midwife or doctor may also suggest having the membranes ruptured to speed up labour.

Assisted delivery

Sometimes your doctor may need to use instruments to help you give birth to your baby. Some of the main reasons why you may need help are listed below.

• Your baby isn't getting enough oxygen, or there is another problem putting his or her health at risk. This is called fetal compromise or fetal distress.

• Your baby is in a position that means it's difficult for him or her to be born without help.

• You have been pushing for a long time, are very tired and can't manage without assistance.

• You have a health condition that means you may not be able to keep pushing.

You will be given regional anaesthesia before an assisted delivery. This completely blocks feeling from the waist down and you will stay awake during the procedure. The two types of assisted delivery are listed below.

• Forceps – these are like large tongs with curved ends that fit around your baby's head. Your doctor will pull gently on them while you push.

• Vacuum extraction (ventouse) – this uses suction. A cup is placed on your baby's head and attached to a vacuum machine. The air is sucked out which attaches the cup strongly to the baby's head. Your doctor then pulls gently on the cup as you push.

If you need an assisted birth, your midwife or doctor will give you more information about your options.

Caesarean delivery

If it's not possible for you to give birth to your baby vaginally, you will need an operation called a caesarean delivery. This involves delivering your baby through your abdomen (tummy).

You may plan in advance to have a caesarean delivery, which is called a planned (elective) caesarean. Or, you may go into labour and then need an emergency caesarean because of complications that develop. It’s possible that you may need an emergency caesarean before you go into labour, but this is less common.

Pain relief

All women cope differently with labour. You may have one idea about the pain relief you wish to have before labour, but change your mind once it's actually happening. There is evidence to show that having someone with you throughout labour can reduce your need for painkillers.

Self-help

There are a number of methods of pain relief that you can try if you don't wish to use medicines. These methods include:

• using breathing and relaxation techniques or massage

• being in warm water, such as in a birthing pool

• moving around, standing up, kneeling and leaning forward

Using a TENS (transcutaneous electrical nerve stimulation) machine can also help in early labour, though it isn't recommended later on. Four electrodes are placed on your back and electrical impulses are sent to the nerves to block pain signals going from your womb to your brain.

If you decide to use medicines, all these self-help methods can also be used at the same time.

Medicines

There are a number of medicines you may be able to choose for pain relief. They can be used in combination if necessary. It's important to talk to your midwife or doctor about these and to be sure that you are aware of the risks and benefits of each.

Gas and air (Entonox)

This is a mixture of nitrous oxide (laughing gas) and oxygen. As you feel a contraction starting, you breathe in the mixture through a mouthpiece or a mask placed over your nose. It's a mild painkiller and will make you less aware of your pain, although not all women find it effective. You may find that Entonox makes you feel sick and light-headed.

Opioids

These medicines include diamorphine and pethidine. They are strong painkillers that are injected into a large muscle in your leg or arm, but may have a limited effect during labour. You may have side-effects including feeling sick, dizzy or very sleepy.

Opioids may also affect your baby making him or her sleepy both at birth and for a few days afterwards. This can reduce your baby's ability to breathe after birth and he or she may need urgent treatment. Opioid medicines can also make it harder for you to breastfeed.

Epidural

This involves having an injection of local anaesthetic into your lower back, just above your waist. An epidural completely blocks feeling from the waist down. It's very effective and nine out of 10 women who have one have no pain at all.

However, there are side-effects. If you have an epidural, your second stage of labour may take longer because you won't feel the urge to push. It may also make moving around more difficult because you have less feeling in your back and legs. However, you may be able to have a mobile epidural.

This uses a lower dose of local anaesthetic plus an opioid painkiller. It allows you to walk about and use different positions that may make your labour easier.