Reasons for induction of labour
If you're in any doubt about why your doctor is suggesting induction of labour, ask for a detailed explanation - this should cover all of the alternatives. In the end, the decision is up to you.
Only five per cent of babies actually come on their due date, but in general, induction is not considered until you are ten days or more past your EDD. Don't worry if you do have to be induced. Induction is fine provided it's done strictly for medical reasons and either for your well-being or the baby's. And please don't feel angry with yourself if your birth doesn't turn out just the way that you'd planned.
Anything that makes the uterine environment unhealthy is a reason for induction. Your labour may be induced if:
- You have hypertension, pre-eclampsia, heart disease, diabetes, or antepartum bleeding.
- There are signs of placental insufficiency (so your baby's in danger of not getting enough nutrients and oxygen from the placenta).
- Your membranes have ruptured but labour hasn't started within 24-48 hours.
- Your pregnancy goes beyond 42 weeks.
How is induction of labour done?
Most obstetric units will normally use a combination of three different methods to induce labour.
The most common method of induction uses prostaglandin pessaries, which soften the cervix and start it dilating. They can be inserted at any time of day, although most units put the first one in at night, particularly in first pregnancies. They usually start to take effect in six hours, although several may need to be used over 24-48 hours. This is a good method of induction as you are free to move around.
Artificial rupture of the membranes (ARM)
This is also known as amniotomy and involves the use of an instrument not unlike a crochet hook. It is inserted through the cervix into the uterus to make a small opening in the membrane so that the waters escape. It can only be performed if the cervix is already partially open. Amniotomy is usually followed in a few hours by contractions, but if there are no contractions you'll need to have an oxytocin drip. If you have a drip, doctors usually advise fetal monitoring so that they can check the effect of the induced contractions on the fetus. Labour usually reaches full intensity quickly after ARM because the baby's head is no longer cushioned and it presses down hard against your cervix, which encourages the uterus to contract and the cervix to dilate. If left alone, the waters don't usually break until late in the first stage.
Amniotomy is not just a method of induction. It will be performed if an electrode needs to be attached to the baby's scalp to monitor his heartbeat. It will also be performed if the baby's heart rate goes down because of distress. In this case, traces of meconium, the baby's first bowel movement, may be seen in the amniotic fluid.
Oxytocin is the natural hormone from the posterior pituitary gland in the brain that stimulates labour. The synthetic form is used for inducing labour.
Oxytocin is given through a drip or syringe drive with careful regulation of the dose. Ask for the drip to be inserted in your left arm if you're right-handed, and check that you can have a long tube connecting you to the drip so you have more room to move around. Some drip stands are on wheels so that you can still move around the room and change position if you wish, which will help you control the more intense labour pains. The oxytocin drip can be turned down if you go into strong labour quickly. The drip won't be removed from your arm until after the baby is born because the uterine contractions help to expel the placenta.
Contractions brought on by an oxytocin drip are often stronger, longer, and more painful than normal contractions, with shorter breaks between them, so there's an increased need for painkilling drugs.
Expectations of induced labour
If properly handled, induced labour needn't be more difficult than natural labour and, using oxytocin, your midwife should be able to get you to the stage where you'll have a normal labour. You can still do all your breathing exercises and push the baby out at your own pace if you prefer to have a natural childbirth. If the induced labour does become too painful, you can ask for epidural anaesthetic or other pain relief.
If you're overdue
Towards the end of pregnancy doctors are always on the look-out for any signs of placental insufficiency as the baby outgrows its food supply.
Whether to induce or not if you're overdue is a controversial issue, so it's worth talking to your midwife about this at one of your antenatal checks. Of course, induction isn't always necessary. A mother who reaches her estimated date of delivery, given that she and the baby are perfectly normal, should be allowed to go into spontaneous labour.
Once the EDD has been passed, though, I do think it's very important to have your own and your baby's condition monitored frequently. If there's any sign of fetal distress, I'd advise you to agree to medical intervention.
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