105. Medical Procedures And Medications In Labour

While many women go into labour on their own, sometimes labour needs to be stimulated or induced for medical reasons. Your labour may be induced if:

• You are 1 to 2 weeks past your expected due date
• Your baby is not growing as she or he should or has a health issue
• Your membranes have ruptured but you have no contractions within 24 hours
• You have high blood pressure in pregnancy
• Fetal monitoring and/or ultrasound show that your baby may not be doing well
• You have diabetes
• Your baby isn’t moving as much as it used to
• The placenta is not supplying the proper amount of nutrients and oxygen to the baby
• Your water has broken and your Group B Strep swab is positive (antibiotics will also be started)

If an induction is advised, your caregiver will discuss the options for you and your baby. Risks may include:

• An increased rate of cesarean birth and epidural anesthesia
• An increased risk of preterm delivery if your due date wasn’t accurate
• Contractions that are too close together , or too strong, may stress your baby
• Emotional stress for you and your partner if the induction does not start labour

Benefits may include the start of labour or a shorter labour. The goal of induction is to achieve a normal labour pattern.

Most methods of induction require your cervix to be “ripe” before they can work well. A “ripe” cervix is soft, low, forward in the vagina, and starting to dilate. (Touch your earlobe to simulate the feel of a ripe cervix)

If labour is induced before your cervix is ready, it may be necessary to prepare or “ripen” it. Methods used to soften or “ripen” your cervix before induction are:

• Prostaglandin gel or a slow release packet may be inserted close to your cervix. The slow release packet, Cervidil has a string attached so it can be removed if contractions start or if the contractions are too forceful
  • Can decrease the oxygen supply to the uterus and baby which can lead to cesarean birth
• A catheter (small rubber tube with a balloon end) is inserted into your cervix during a vaginal exam. The balloon is then inflated with sterile water to put pressure on the cervical opening. The end that extends outside your vagina is taped to your upper thigh. This works to dilate your cervix causing it to open 3 to 4 cm. It can cause some cramping and may start labour on its own. If labour does not start after “ripening” with the catheter your cervix should be ready for other methods of induction to work.

These methods of getting your cervix ready for labour may need to be repeated or they may start your labour.

• There are 3 methods used to induce labour once your cervix is “ripe”

Prostaglandin vaginal gel

• Prostaglandin vaginal gel may be inserted into your vagina to stimulate labour

Artificial Rupture of Membranes

• This procedure is done during a vaginal examination
• Artificially breaking or rupturing your waters may be done at any time before or during labour
• This procedure releases some of the amniotic fluid surrounding your baby. It may stimulate contractions by causing direct pressure of your baby’s head against your cervix. The pressure causes the release of prostaglandins which “ripen” or soften the cervix and stimulate contractions
• Sometimes the membranes are ruptured to allow for the insertion of an internal fetal monitor to obtain a more accurate reading of your baby’s heart rate
  • Once your membranes have been ruptured your labour is then “on the clock”. The membranes provide a protective barrier against infection and once it is gone there is increased risk to you and your baby if your labour is prolonged
  • The membranes and amniotic fluid act as a cushion between your cervix and the babies head. Once that cushion is gone the intensity of the contractions is increased. This may catch some women by surprise and they may find it harder to cope with this new intensity, however this may also speed up labour. Have your breathing and relaxing comfort measures ready

Oxytocin Induction

• Oxytocin is a hormone produced by your body to stimulate your uterus to contract. A synthetic oxytocin (pitocin, syntocinon) is given by intravenous (IV) to induce labour
• The IV is regulated by your nurse through a pump which gives you an exact amount of the drug. The dosage is increased slowly until strong contractions are every 2 to 3 minutes or a safe maximum dosage is reached
• A synthetic oxytocin induction requires close monitoring of both mother and baby. This may include continuous electronic fetal monitoring once active labour begins
• Unfortunately, inducing labour doesn’t always work the first time. It may need to be repeated
  • A labour that is induced or augmented with synthetic oxytocin may be faster and more intense than normal labour. A woman may need extra support to cope with the contractions that come on fast and are more painful and closer together.
  • Babies of mothers that have had synthetic oxytocin induction may be at an increased risk for jaundice. Some of the medication reaches the baby during labour and it may take longer for the baby’s liver to break it down
  • Induction with synthetic oxytocin increases the risk of cesarean birth