Many women hope to have a vaginal birth after c-section (VBAC).
It’s important these women are armed with knowledge and accurate information.
There are many myths surrounding VBACs but none is so pervasive as the belief a woman can’t be induced with a VBAC.
Although it’s preferable for labour to start on its own, there are certain medical situations where the immediate birth of the baby becomes necessary.
Can You Be Induced With A VBAC?
In such cases, women should be aware that an elective c-section is not the only possibility. For women who want a VBAC, induction is also an option.
What Is A VBAC?
VBAC means vaginal birth after c-section, where a woman plans to give birth vaginally after a prior c-section.
There are many reasons why a woman will choose to have a VBAC.
- She might have had an unplanned c-section after wanting a normal birth.
- An elective c-section might have been necessary in a previous birth, but doesn’t apply to this pregnancy.
- She understands VBAC is a safe option for her.
Fo whatever reason a woman chooses a VBAC, she needs the full support of her care provider. Leading health organisations around the world recommend VBAC as a safe option for low risk women.
What Is Induction?
Induction of labour is the medical process of beginning labour before it starts on its own, or spontaneously.
Induction might become necessary if the risk of prolonging a pregnancy outweighs the risk of the baby being born immediately.
Complications that make an induction necessary include: preeclampsia; high blood pressure; fetal distress; and maternal health problems such as diabetes or kidney disease.
Unfortunately, inductions are often performed for non medical reasons, and there are increased risks associated with this intervention.
In a medical emergency, however, an induction can give women the opportunity to avoid an elective c-section and attempt a vaginal birth.
This is important when women are facing medically necessary inductions and wish to make informed choices about their labour and birth.
Can VBAC Women Be Induced?
For women who wish to have a vaginal birth after c-section, there is a lot of confusion around whether induction is an option for them.
They might be told it’s dangerous to use synthetic oxytocin to induce or augment women who are attempting a VBAC because it increases the risk of uterine rupture.
This information doesn’t come only from the Internet or birth forums, but also from doctors and care providers.
Uterine rupture is a very real concern.
However, it is an increased risk for all women undergoing induction of labour with synthetic oxytocin, not just for those women who have a uterine scar from c-section.
For women with a uterine scar, there are a few things to take into consideration.
These include the type of scar she has, the drug and dosage being used for induction, and the risk of uterine rupture (scar opening) as opposed to dehiscence (scar stretching).
A number of studies have looked at the increased risk of uterine rupture due to induction. This study found uterine rupture risks were:
- 0.15% in spontaneous labour without augmentation
- 1.91% in spontaneous labour with augmentation
- 0.54% for induction with synthetic oxytocin
- 0.68% for induction with prostaglandin
- 0.88% for induction with rate of rupture and prostaglandin combined.
This indicates women who are hoping for a VBAC and might need to be induced have a very low risk of uterine rupture. How the risk is managed depends greatly on the attitude and support of their care providers, the method of induction used, and the ways in which the women are supported during labour.
How Did This Myth Begin?
It is true there is a slightly increased risk of uterine rupture for women having VBAC. However the overall risk is very low. It doesn’t necessarily mean an induction with synthetic oxytocin will result in uterine rupture.
Even so, induction of VBAC is spoken about as being excessively dangerous. How did this information become so entrenched in our minds as though it were the truth?
The belief that induction of VBAC increases the risk of uterine rupture seems to have stemmed from a misinterpretation of health guidelines and the insert of the actual drug used to induce labour.
The 2010 VBAC Practice Bulletin No. 115, produced by the American Congress of Obstetricians & Gynecologists (ACOG) states:
“Induction of labor for maternal or fetal indications remains an option in women undergoing TOLAC [trial of labor after cesarean]… However, the potential increased risk of uterine rupture associated with any induction, and the potential decreased possibility of achieving VBAC, should be discussed”.
When reading this statement carefully, it should be noted ACOG makes this distinction: there is an increased risk of uterine rupture associated with any induction – not just VBAC.
There is also misinterpretation of the insert for the medication given to induce or augment labour, known as Pitocin in the US and Syntocinon in the UK and Australia.
The insert for Pitocin states:
“Except in unusual circumstances, oxytocin should not be administered in the following conditions: fetal distress, hydramnios, partial placenta previa, prematurity, borderline cephalopelvic disproportion, and any condition in which there is a predisposition for uterine rupture, such as previous major surgery on the cervix or uterus including cesarean section, overdistention of the uterus, grand multiparity, or past history of uterine sepsis or of traumatic delivery”.
Most people assume the line “and any condition in which there is a predisposition for uterine rupture, such as previous major surgery on the cervix or uterus including cesarean section” means the drug shouldn’t be used for VBAC.
However, a previous c-section surgery is NOT listed under the contraindications section of the drug insert.
So what’s the difference between precautions and contraindications and why isn’t c-section listed as a reason not to induce VBAC?
Precautions are the conditions in which the benefits of using synthetic oxytocin to induce labour might outweigh the risks, and should be evaluated on an individual basis to decide what is best for each mother-baby pair.
Contraindications are conditions where the risk of using synthetic oxytocin always outweigh the possible benefits. The contraindications for Pitocin are listed as:
- Where there is significant cephalopelvic disproportion;
- In unfavorable fetal positions or presentations, such as transverse lies, which are undeliverable without conversion prior to delivery;
- In obstetrical emergencies where the benefit-to-risk ratio for either the fetus or the mother favors surgical intervention;
- In fetal distress where delivery is not imminent;
- Where adequate uterine activity fails to achieve satisfactory progress;
- Where the uterus is already hyperactive or hypertonic;
- In cases where vaginal delivery is contraindicated, such as invasive cervical carcinoma, active herpes genitalis, total placenta previa, vasa previa, and cord presentation or prolapse of the cord;
- In patients with hypersensitivity to the drug.
So What’s The Best Choice?
While it is always preferable for labour to begin on its own, or spontaneously, there are certain situations where the immediate birth of the baby becomes necessary.
In these situations, women planning a VBAC can review the risks and benefits of having another c-section or choosing to be induced and attempt a vaginal birth.
ACOG’s latest VBAC recommendations state:
“Respect for patient autonomy supports the concept that patients should be allowed to accept increased levels of risk”.
Some women will willingly accept an increased risk of uterine rupture with induction because they prefer to avoid an elective c-section.
Other women will make the decision to accept the risks of a repeat c-section and avoid the increased risk of uterine rupture.
Each woman’s individual situation should be considered, and the decision she makes should be informed, and based on facts.