Labour and Birth

Special cases of vaginal birth

Special cases of vaginal birth

The following special cases of vaginal birth highlight specific circumstances where women may have expected to have elective caesarean births, but who may wish to consider vaginal birth. The following information is general in nature and does not replace your informed consent discussion with your obstetrician based upon your individual circumstances, preferences and the hospital at which you choose to birth your baby/babies. More information on elective caesarean birth can be found in the chapter Elective/planned caesarean birth.

Vaginal birth after caesarean birth (VBAC)

If you have previously had a caesarean birth, it may be possible to birth your baby vaginally this time. The planned option to try for a vaginal birth after a caesarean birth is called a Trial of Labour (TOL). Successful vaginal birth after a TOL is called Vaginal Birth After Caesarean (VBAC). The planned option to have a caesarean birth after one or two past caesarean births is called an Elective Repeat Caesarean Section (ERCS).

A woman who has previously had a caesarean birth has the option to try a vaginal birth or to choose an elective caesarean birth following an informed consent discussion of the benefits and risks with her obstetrician. For every 100 women who try for a VBAC, an average of 70 will have a vaginal birth and the rest will have a caesarean birth. The likelihood of a successful VBAC depends on the reason for the previous caesarean birth and how labour progresses during the TOL. There are some reasons why a TOL may be inadvisable and these include: more than two previous caesarean births, placenta praevia, the baby is not presenting head-first, uterine fibroids, previous surgery to the upper part of the uterus, and certain medical conditions in the mother.

Benefits and risks

Both VBAC and ERCS have associated benefits and risks. The issues around which option is best for any particular woman are complex and the decision to birth by VBAC or ERCS should be individualised. Please discuss these with your obstetrician in your informed consent discussion.

What can I expect in a TOL?

Generally speaking, a planned TOL will be similar to a normal labour. If you decide to try for a VBAC, these are some things you might expect in labour:

  • Your labour will likely start and proceed normally. If augmentation with Syntocinon infusion is used, it will usually be for a shorter duration and at a lower dose to avoid overstimulating the uterus
  • During active labour you and your baby’s wellbeing and progress will be closely monitored by your midwife. This will involve continuous fetal heart rate monitoring and you may have an IV infusion commenced
  • You will be encouraged to mobilise and use positions which are comfortable for you
  • Various methods of pain relief will be available to you, including epidural
  • If labour does not progress normally, or if complications arise, a caesarean birth is recommended
Birthing twins

It is common for mothers with twin pregnancies and HOMs (Higher Order Multiples, such as triplets or more) to elect to birth their babies by planned caesarean. About 1 in 2 twin pregnancies and 9 out of 10 HOMs are birthed by caesarean in Australia. The decision on how and when to birth twins and HOMs should be made in consultation with your obstetrician based on an informed discussion of the benefits and risks of each option in accordance with your particular circumstances.

In general, planned caesarean birth is recommended in the following circumstances:

  • In twins, when the first baby is not presenting head-first e.g. breech
  • In twins, when the second baby is larger than the first
  • In twins, where they share an amniotic sac
  • For HOMs – triplets and more
  • Where there are any pregnancy complications or pre-existing conditions in the mother or babies that make caesarean birth a safer option. Some of these include: prematurity, pre-eclampsia, bleeding in pregnancy, gestational diabetes, growth restriction and twin to twin transfusion syndrome.
What factors should be considered in deciding when and how to birth twins?

Under certain circumstances, where there are no complications, and where this is carefully planned, it is possible for mothers with twin pregnancies to labour and safely birth their babies vaginally. The most favourable conditions for birthing twins vaginally occur when both twins are presenting head-first (this is the case in approximately 4 in 10 twin pregnancies), they have separate amniotic sacs and they are of a similar size. When considering the best time for twins to be born, it appears that 37 weeks is an optimal time to birth twins, whether vaginally or by planned caesarean birth. The most recent Australian study on when to birth twins concluded that women with uncomplicated twin pregnancies who electively birthed their babies at 37 weeks gestation (whether vaginally or by caesarean birth) had better neonatal outcomes than those who birthed their twins at 38 weeks or later. There were no significant differences in outcomes for the mothers’ wellbeing in this study regardless of birth mode or whether labour was induced or not. A link to this information can be found in the Resources.

What can I expect during labour and birthing twins vaginally?

In many respects, labouring with and birthing twins vaginally will be similar to a normal labour with a singleton when the first twin presents head-first. Additionally, you may expect the following:

  • Your babies will be continuously monitored by CTG throughout labour and birth. It will be important to not only distinguish between each baby’s fetal heart rate, but to also differentiate the babies’ heart rates from your own pulse. When possible, the first twin’s heart rate will be continuously monitored using the fetal scalp electrode. This will require the membranes of the first twin to be ruptured.
  • You will have an IV infusion and may have Syntocinon augmentation if progress slows
  • Various methods of pain relief, as discussed above, will be available to you, including epidural. Epidural is recommended in anticipation that assisted, instrumental or caesarean birthing may be required.
  • You will be encouraged to use positions which are comfortable for you
  • The first twin will usually be birthed normally, as described above. The second twin’s amniotic sac may be artificially ruptured by your obstetrician. It is expected that the second twin will be birthed within around 30 minutes. Your obstetrician and midwife will assist and guide you through the birth where necessary. Sometimes assisted , instrumental or caesarean birthing may be required for the second twin.
  • The Anaesthetist, Paediatrician and Neonatal Team may be present for the birth
  • It is common practice to place one cord clamp on the first twin and two on the second twin to differentiate between them
  • The placenta will be birthed after both babies are born
  • The IV infusion will continue after the birth
  • Depending on the condition and maturity of the babies, they may need to be cared for in a Special Care Nursery or Neonatal Unit

A link to this information can be found in the Resources.

Breech birth

Most babies are born head-first, but about 1 in 25-33 babies will present by the breech (bottom, feet or both) at term. In the Pregnancy section we briefly looked at the options available, such as External Cephalic Version to turn the baby to a head first position, planning an elective caesarean birth or choosing a vaginal breech birth. The available evidence comparing planned caesarean birth with planned vaginal breech birth indicates that for a planned caesarean birth, there are slightly increased risks for the mother compared to vaginal birth (as there are for caesarean births in general). For the baby, planned caesarean birth appears to be safer than vaginal breech birth, which is associated with around a 1 in 25-50 increased chance of short-term birth complications. Expert opinion is divided on the findings of the study on which this information is based (Term Breech Trial) despite the current trend towards planned caesarean birth for most cases of breech presentation. Again, the best option for you will depend on your individual circumstances, preferences and the outcome of your informed decision making discussion with your obstetrician.

What can I expect during the labour and birth?

The labour and birth will be similar to that described above for normal vaginal birth. For a breech baby, you may expect:

  • Labour will ideally commence and proceed normally without induction. Augmentation may be considered if progress slows
  • An active labour, encouraging an upright position is recommended
  • The baby’s heart rate is continuously monitored with the CTG throughout labour and birth
  • Various methods of pain relief will be available to you, including epidural
  • You will have an IV infusion if you elect to have an epidural
  • The second stage may be extended to allow the baby’s breech to descend well into the birth canal prior to active pushing
  • The obstetrician will assist the baby’s birth. Forceps may be used to guide the baby’s head out gently
  • The Paediatrician and Neonatal Team will likely be present at the birth
  • An emergency caesarean birth is recommended if progress slows or complications arise