If you have had a caesarean section (CS), you may be thinking about how to give birth next time. Planning for a vaginal birth after caesarean (VBAC) or choosing an elective repeat caesarean section (ERCS) have different benefits and risks. You will usually have the elective CS after 39 weeks of pregnancy. This is because babies born by CS earlier than this are more likely to need to be admitted to the special care baby unit for help with their breathing.
In considering your options, your previous pregnancies and medical history are important factors to take into account, including:
- The reason you had your CS
- Whether you have had a previous vaginal birth
- Whether there were any complications at the time or during your recovery
- The type of cut that was made in your uterus (womb)
- How you felt about your previous birth
- Whether your current pregnancy has been straightforward or whether there have been any problems or complications
- Wow many more babies you are hoping to have in future; the risks increase with each CS, so if you plan to have more babies it may be better to try to avoid another CS if possible.
To help you decide, your healthcare professionals will discuss your birth options with you at your antenatal visit, ideally before 28 weeks.
What if I have had more than one caesarean section?
If you are considering a vaginal birth but have had more than one CS you should have a detailed discussion with a senior obstetrician about the potential risks, benefits and success rate in your individual situation.
What are my chances of a successful VBAC?
After one caesarean section, about three out of four women (75%) with a straightforward pregnancy who go into labour naturally give birth vaginally.
A number of factors make a successful vaginal birth more likely, including:
- Previous vaginal birth, particularly if you have had previous successful VBAC; if you have had a vaginal birth, either before or after your caesarean section, about 8–9 out of 10 women can have another vaginal birth.
- Your labour starting naturally.
- Your body mass index (BMI) at booking being less than 30.
What are the disadvantages of VBAC?
- 25 in 100 women may need to have an emergency CS caesarean section during labour. This is only slightly higher than if you were labouring for the first time, when the chance of an emergency CS is 20 in 100 women. An emergency caesarean section carries more risks than a planned caesarean section.
- You have a slightly higher chance of needing a blood transfusion compared with women who choose a planned second CS.
- The scar on your uterus may separate and/or tear (rupture). This can occur in 1 in 200 women. This risk increases by 2 to 3 times if your labour is induced. If there are warning signs of these complications, your baby will be delivered by emergency CS. Serious consequences for you and your baby are rare.
- Serious risk to your baby such as brain injury or stillbirth is higher than for a planned caesarean section but is the same as if you were labouring for the first time.
- You may need an assisted vaginal birth using ventouse or forceps.
- You may experience a tear involving the muscle that controls the anus or rectum (third or fourth degree tear).
When is VBAC not advisable?
VBAC is normally an option for most women but it is not advisable when:
- you have had three or more previous caesarean deliveries
- your uterus has ruptured during a previous labour
- your previous CS was ‘classical’, i.e. where the incision involved the upper part of the uterus
- you have other pregnancy complications that require a planned CS.
What are the advantages of ERCS?
- There is a smaller risk of uterine scar rupture (1 in 1000).
- It avoids the risks of labour and the rare serious risks to your baby (2 in 1000).
- You will know the date of planned birth. However, 1 in 10 women go into labour before this date and sometimes this date may be changed for other reasons.
What are the disadvantages of ERCS?
- A repeat CS usually takes longer than the first operation because of scar tissue. Scar tissue may also make the operation more difficult and can result in damage to your bowel or bladder.
- You can get a wound infection that can take several weeks to heal.
- You may need a blood transfusion.
- You have a higher risk of developing a blood clot (thrombosis) in the legs (deep vein thrombosis) or lungs (pulmonary embolism).
- You may have a longer recovery period and may need extra help at home. You will be unable to drive for about 6 weeks after surgery.
- You are more likely to need a planned CS in future pregnancies. More scar tissue occurs with each CS, which subsequently increases the possibility of the placenta growing into the scar, making it difficult to remove during any future deliveries (placenta accreta or percreta). This can result in bleeding and may require a hysterectomy. All serious risks increase with every CS you have.
- Your baby’s skin may be cut at the time of CS. This happens in 2 out of every 100 babies delivered by CS, but usually heals without any further harm.
- Breathing problems for your baby are quite common after CS but usually do not last long. Between 4 and 5 in 100 babies born by planned CS at or after 39 weeks have breathing problems compared with 2 to 3 in 100 following VBAC. There is a higher risk if you have a planned CS earlier than 39 weeks (6 in 100 babies at 38 weeks).
What happens when I go into labour if you are planning a VBAC?
You will be advised to give birth in hospital so that an emergency CS can be carried out if necessary. Contact the hospital and your obstetrician as soon as you think you have gone into labour or if your waters break.
Once you start having regular contractions, you will be advised to have your baby’s heartbeat monitored continuously during labour. This is to ensure your baby’s wellbeing, since changes in the heartbeat pattern can be an early sign of problems with your previous caesarean scar. You can choose various options for pain relief, including an epidural.
What happens if you do not go into labour when planning a VBAC?
If labour does not start by 41 completed weeks, your obstetrician will discuss your birth options again with you. These may include:
- continue to wait for labour to start naturally
- induction of labour; this can increase the risk of scar rupture and lowers the chance of a successful VBAC
- ERCS.
What happens if you have an ERCS planned but you go into labour?
Let your maternity team know what is happening. It is likely that an emergency CS will be offered once labour is confirmed. If labour is very advanced, it may be safer for you and your baby to have a vaginal birth. Your obstetrician will discuss this with you.
Dr Efterpi Tingi
Consultant Obstetrician and Gynaecologist
