Childbirth

Reviewed by Dr Philip Owen, consultant obstetrician and gynaecologist

Most women give birth without complications.

The birth starts with the onset of labour, which is usually marked by the beginning of regular uterine contractions. These are felt as tightenings either in the back or across the top of the womb. Sometimes the baby's waters break before the beginning of the contractions or, more commonly, once labour is under way.

Role of the midwife
The midwife's role during birth is to guide, support and observe, and to make sure everything goes well.

The midwife should make sure the mother-to-be feels safe and finds birth as rewarding as possible.
A mucous show is often passed through the vagina at the beginning of labour, which may have streaks of blood in it. Some women pass the show days before going into labour, other women do not pass a show at all, so it is not a reliable sign of labour.

During a natural birth, the muscles in the uterus (womb) contract and it's this contraction that's felt as labour pains. Labour is a painful experience, but breathing techniques learned in antenatal classes can make early labour less stressful.

The contractions cause the baby's head to be pressed down through the pelvis and against the inside of the cervix. This causes the cervix to stretch open (dilate) allowing the baby's head to pass through (descend) into the vagina and onwards into the outside world.

What are the phases of birth?
The first stage of labour
The birth begins when labour contractions start becoming frequent, intense and of sufficient duration to cause the cervix to open. At the beginning of labour, you will usually be examined externally (abdominal examination), to see how the baby is lying and to be certain that the baby is coming head first.

An internal examination is performed to see what is happening to the cervix (neck of the womb). Before labour begins, your cervix is about 3cm long and closed (not dilated).

When labour starts, the cervix gets shorter (a process called effacement) and opens (dilates). The cervix is fully dilated when it has opened 10cm. During labour, it's important you don't start pushing before you are fully dilated, because there will be a danger of tearing the cervix.

Once your cervix has fully dilated, the first stage of labour is completed and the second stage is about to begin. The first stage generally lasts up to 12 hours in a first labour and seven hours in subsequent deliveries, but each labour is different.

The second stage of labour
The second stage starts when your cervix is completely open (10cm). Usually, there is a sensation of fullness in your vagina or bowel and you wish to push.

Most women will find that the labour pains in the second stage of labour are more bearable, because you can now actively help yourself by pushing.

The second stage of labour ends with the delivery of the baby. It usually lasts for 45 minutes to two hours in a first labour and 15 to 45 minutes in subsequent deliveries.

The third stage of labour
During this stage the afterbirth (placenta) is delivered. The placenta is usually delivered within 5 to 15 minutes after the birth of the baby.

The last stage of birth is a co-operation between yourself and the midwife, although little effort is required to deliver the placenta.

After your baby's born, it's routine that you will be given an injection to stimulate the uterus to contract, which helps delivery of the placenta.

Making the uterus contract in this way reduces the risk of heavy bleeding during delivery of the placenta (post-partum haemorrhage).

How are mother and baby monitored during labour?
Your blood pressure, pulse and temperature will be checked at regular intervals throughout labour and after the delivery.

It is usual to monitor the baby by listening to its heartbeat. This is commonly done by listening to the heart with a special hand-held amplifier, recording the heart rate at regular intervals.

In certain circumstances, it can be necessary to have a continuous recording of the baby's heartbeat. This can be obtained via a belt placed around the mother's waist. Alternatively, a small electrode can be placed on the baby's scalp via your cervix.

By analysing the baby's heartbeat in these ways, the midwife or obstetrician is able to detect whether the baby is receiving enough oxygen during the course of the labour.

Occasionally, the heartbeat pattern shows abnormalities and the obstetrician may need to take a small sample of blood from the baby's scalp to analyse the oxygen content (foetal scalp sampling).

Breech birth
Turning baby
One option for a breech birth is for your obstetrician to try to gently turn the baby before labour begins.

This is done by massaging the abdomen.

The procedure is known as external cephalic version (ECV).

ECV is only recommended at term (37-42 weeks), in case the baby becomes distressed and needs to be delivered immediately.
For birth, the best position for your baby is to be head first in the womb. In a breech birth, the baby is positioned with its head near the mother's ribs and its bottom over her cervix. Because the baby's bottom is slightly smaller than its head, there may be difficulty giving birth safely.

Many breech babies can be delivered safely, and mothers who have had a normal birth before will have fewer difficulties.

Complications may arise for mother and baby in a breech birth: there should always be an obstetrician and anaesthetist present as well as the midwife.

It may be necessary to use forceps to deliver the baby's head, or the obstetrician may decide to perform an emergency Caesarean section.

If a breech baby is detected during pregnancy, and turning the baby is not an option or unsuccessful, many women will choose to have an elective Caesarean section in advance. This should be discussed carefully with your obstetrician.

Birth with forceps or ventouse cap
Between 5 and 20 per cent of all births require the help of forceps or the ventouse cap (suction cap). This type of delivery is known as instrumental delivery.

An instrumental delivery is performed by an obstetrician who will use forceps or ventouse only under certain circumstances. It is only performed in the second stage of labour.

The most frequent reasons for using forceps or ventouse are:

the baby has an abnormal heart rate recording, suggesting lack of oxygen (foetal distress).
there has been a long period of pushing and birth is not imminent.
the mother is exhausted and has no more energy to push.
the baby's head is in an unusual position in the pelvis.
When an instrumental delivery is necessary, the doctor puts the forceps or the ventouse cap on the baby's head, then pulls carefully to ease the baby out.

When using forceps or ventouse, it may be necessary to make a cut, known as an episiotomy, in the mother's perineum - the area between the vagina and the anus. An episiotomy can also be required in an otherwise straightforward (non-instrumental) delivery.

If the use of forceps or suction cap is not successful, it may be necessary to perform an emergency Caesarean section.

For the first couple of days after the birth, the baby will have marks from where the forceps or suction discs were placed, but these will disappear quickly and are not dangerous.

Pain relieving medication
There are different kinds of pain relief that can be offered during childbirth. Some women decide in advance they don't want to use any pain relieving drugs (analgesia), but may change their mind during labour.

Analgesia is prescribed by a doctor or midwife after discussion with the mother. The most frequently used drugs are listed below.

Gas and air (Entonox)
This can be used throughout labour and is particularly useful in the first stage. There are no major side effects for mother or baby.

With the correct technique, good pain relief can be achieved. Be sure to ask the midwife to demonstrate the correct technique.

Morphine or pethidine
These are strong painkillers given via an intramuscular injection. They are often used in combination with Entonox. Serious side effects are rare. Minor side effects are the mother may become drowsy, develop an itchy nose or feel nauseous.

The drugs cross into the baby's bloodstream and, occasionally, the baby may be slow to start breathing when born. If this is the case, the midwife or paediatrician will give the baby a drug called Narcan (naloxone) to reverse the effects of the painkiller.

These painkillers are given once or twice during the course of labour. Women do not become hooked on them.

Epidural and spinal anaesthesia
These techniques are provided by anaesthetists. They both involve placing a tube or needle near the spinal cord in the lower region of the back. They usually provide excellent pain relief.

An epidural is long lasting and is suitable from the beginning of labour right through to the delivery.

A spinal anaesthesia is for short-term use, say for a forceps delivery or Caesarean section.

Serious side effects from epidural and spinal anaesthesia are rare, and midwives and anaesthetists are trained to watch out for them.

Epidurals do not make the labour slower, but sometimes make it more difficult for you to push effectively in the second stage of labour.

Tears in the vagina or perineum
If the skin around the vagina has been torn, or cut in an episiotomy, it will usually need to be stitched. Many women are nervous about whether or not cuts and tears will heal again after the birth, but fortunately most do.

Most women will be given some local anaesthesia in the perineum and in the vagina (or some other form of anaesthetic) before receiving stitches. This is done with a local injection (similar to having an injection at the dentist). Dissolving stitches are used so they do not need to be removed.

What if the muscle of the anus tears?
Very few women will experience their anal sphincter tearing during childbirth. This usually only happens if the baby is very big, but it can also sometimes be torn if the doctor uses forceps or a ventouse.

The sphincter will be stitched up by a doctor and this is usually performed under a spinal, epidural or general anaesthetic because it can otherwise be painful.

If you experience any kind of incontinence after childbirth, you should consult your doctor. Regular muscle tightening exercises help reduce the chance of this happening. All women can benefit from doing these in the weeks following birth. The midwife can explain what to do.