Contractions are a sign that your baby is on the way. But what are they and what do they do?
Posted: 19 August 2011
by Anne Richley, midwife
When we talk about labour, a great deal of the focus is on the actual contractions.
There’s often an assumption that everyone knows what a contraction is when, in reality, many women have no idea. Understanding what’s happening to your body as it’s having a contraction helps reduce the fear of the unknown.
How do contractions work?
A contraction is when the muscles of the uterus tense and relax, passing in waves from the top, travelling inwards and downwards. During the first stage of labour, they begin to ‘take up’ the neck of the uterus (this is called effacement), making it thinner so it’s no longer tube-shaped, but it can be felt as a thin rim around the baby’s head by the midwife.
As these muscles stretch and relax, the neck of the uterus (cervix) starts to open until it’s fully dilated, and then the baby moves deeper into your pelvis – and the first stage of labour is complete.
During the second stage of labour, contractions play a different role, pushing your baby down the birth canal.
After he’s born, further contractions push out the placenta, which completes the third and final stage of labour.
What do contractions feel like?
Although a contraction affects the whole of the uterus, some women only feel it in one area of their abdomen or back. Most consider labour to be painful, but it tends to start gradually and build up, with the contractions intensifying as the cervix becomes more dilated.
Some mums-to-be feel the pain through every nerve ending, whereas others find it easier to bear. After each contraction there’s a period of rest, which helps you to relax and prepare for the next one. Contractions are temporary, and for many women it’s this thought and the ‘prize’ at the end that helps them to cope.
When will contractions start?
Some women experience irregular contractions in the days before labour really kicks in properly, but none of it is ‘wasted’. Often during this time the cervix begins to soften, move forward and become thinner, which is all part of effacement. Most women’s labour begins after 37 weeks, with period-like pains that eventually have some regularity to them, lasting longer and becoming stronger.
Braxton Hicks tightenings are ‘practice’ contractions, which can feel irregular and uncomfortable, but they shouldn’t be painful. If you’re concerned that you may be experiencing contractions before the 37th week of pregnancy, you should contact your maternity unit to get checked over as your baby will be considered premature.
How do you push?
For the majority of women, the contractions in the second stage of labour feel very different to the first stage, and this is because they’re doing a different job. As your cervix is fully dilated these contractions have an ‘expulsive’ effect, causing an involuntary, overwhelming sensation to ‘bear down’ so that your baby is pushed out. Many women find this stage easier and don’t need to be guided – they just go with their body and automatically push with the contraction.
If you have an epidural and can’t feel the contractions, your midwife will instruct you on when to push. By placing her hand on your abdomen, she’ll be able to feel the contraction and tell you to take a deep breath, put your chin down to your chest and push into your bottom. Even if you have an assisted birth (forceps or ventouse), you’ll still need to push to help move the baby down.
What if your contractions slow down?
Sometimes contractions can slow down or stop during labour, which can be disheartening. But staying upright and walking around will encourage them to keep coming. Nipple stimulation produces the hormone oxytocin, which can get your uterus contracting again, but if this doesn’t work the midwife may use a synthetic form, called Syntocinon.
This is given via an intravenous drip in the hand. If you become very tired or have an epidural, contractions are more likely to slow down. With natural childbirth, it can also indicate transition – the period where the cervix is fully dilated – but there’s a period of rest before the pushing begins.
Delivering the placenta
Most mums-to-be get ‘clear messages’ at each stage of labour, as the contractions change, but this isn’t the case for everyone. Sometimes the stages ‘overlap’ and most women aren’t really aware of the contractions associated with the third stage of labour, as they’re so preoccupied with gazing at their newborn.
