Natural Birth After a Cesarean Section: Is VBAC Right for You?

In short: Vaginal birth after a previous caesarean is usually possible and safe, with a success rate of about 72–75%, rising to about 90% in women who have had a vaginal birth before. The risk of rupture of the uterus is about 0.5%. Conditions: one previous caesarean with a low transverse scar, the baby head-down and no other reason against vaginal birth. It is not advised with a vertical scar on the upper uterus, a previous rupture or placenta praevia.

Many expecting mothers who had a cesarean section in a previous pregnancy hope for a natural, vaginal birth this time. This is known medically as VBAC (vaginal birth after cesarean), and it is a safe and reasonable option for many women when carefully selected and closely monitored. Below, we explain who is a good candidate, what to watch for, and how your care team keeps you and your baby safe throughout the process.

It is known that the rate of caesarean section births has increased recently worldwide due to:

• Increasing the use of continuous fetal monitoring during natural birth, which leads to increased detection of changes in the fetal heartbeat that require emergency caesarean sections.
• Increasing the rate of obesity, which leads to difficulty in natural childbirth (labor dystocia).
• increased maternal age at conception and childbirth due to women’s preference to delay marriage and pregnancy for reasons of career and education.
• Increase in the percentage of maternal requests for an elective caesarean section due to the mother’s fear of pain during natural childbirth.

Because of this, many pregnant women today have had a previous cesarean delivery, and most of them hope for a natural birth in their next pregnancy. The good news is that, with the right conditions, this is often possible.

In what cases do we allow natural birth after a previous caesarean section?

• Ideally there should be only one previous low-transverse caesarean section; women with two previous caesareans may still be offered a VBAC after careful counselling, in a hospital equipped for immediate caesarean section.
• The fetus’s head should be facing downward in this pregnancy (cephalic presentation).
• VBAC is usually planned at term (37 weeks or more), but if labour starts earlier, a vaginal birth is still possible and has similar chances of success.
• There should be no contraindications to natural birth in general (a low lying placenta, a breech fetus, the fetus’s condition does not allow for a natural birth, that is, the fetus’s condition is unstable and the birth must take place quickly, the mother’s condition does not allow for a natural birth, that is, the mother’s condition is unstable and must give birth quickly)

What are the contraindications for natural birth after a cesarean section?

• The uterine incision in the previous cesarean section is located in the upper part of the uterus (classical incision)
• The previous uterine cesarean incision was atypical (J-shaped or T-shaped).
• There is a previous history of uterine rupture during previous natural births.
• Some types of previous uterine surgeries, such as performing a procedure to remove uterine fibroids and breaching the uterine cavity.

What are the signs that increase the success rate of natural birth in subsequent pregnancies after a previous cesarean section?

• Having a natural birth in a previous pregnancy, this raises the success rate of a natural birth to 90 percent.
• The birth should be spontaneous (uterine contractions begin spontaneously), as the need to induce labor reduces the chances of a successful natural birth in general.
• The reason for performing a cesarean section in the previous pregnancy was fetal distress or fetal malpresentation. If the previous cesarean section was due to failure to progress, this reduces the chances of a successful natural birth in the subsequent pregnancy.

Other favorable factors include increased maternal height, a BMI under 30, and a maternal age under 40 years.

The estimated weight of the fetus should also be less than 4 kg, and the gestational age should be less than 40 weeks for the best chances of success.

What are the concerns of vaginal birth after a previous cesarean section?

The main concern is rupture of the uterus during natural birth, which poses a risk to the mother’s life (bleeding and the need for a hysterectomy) and poses a risk to the fetus’s life (hypoxia or death). This is why careful patient selection and monitoring are so important.

How is the natural birth monitored for a woman who has had a previous caesarean section?

• Monitoring the fetus through continuous fetal heart monitoring throughout the birth process
• Monitoring the symptoms of the mother (severe abdominal pain that does not respond to painkillers, abdominal pain other than during uterine contractions)
• Monitoring the mother’s vital signs during childbirth
• Monitor the progress of cervical dilatation and descent of the fetal head into the pelvis as expected

What are the signs of uterine rupture during natural birth?

• abnormalities in fetal heart rate
• Severe pain in the mother’s abdomen that does not respond to painkillers and is present at times other than uterine contractions.
• Vaginal bleeding
• hematuria
• The mother’s blood pressure drops, her heart rate increases, and she goes into shock
• The fetal parts are palpable on the external abdominal examination
• Loss of uterine contractions that were previously present

Is it possible to induce labor for women who have had a previous caesarean section?

Yes, but induction increases the risk of uterine rupture (about 2–3 times with prostaglandin pessaries/suppositories, which are therefore used with great caution or avoided). Mechanical methods such as a balloon (Foley) catheter, breaking the waters, and carefully monitored oxytocin are usually preferred, and the decision is made by a senior obstetrician.

What is the success rate of natural birth after a previous caesarean section?

72-75 percent.

Is a natural birth possible after more than one previous caesarean section?

Yes, it is possible after careful counselling, but the risk of uterine rupture rises with the number of previous cesarean deliveries (roughly 1–2 percent after two cesareans, compared with about 0.5 percent after one).

What is the incidence of uterine rupture during natural birth after a previous cesarean section?

0.5 percent.

If you have had a previous cesarean section and are hoping for a natural birth this time, it is important to discuss your individual situation with your obstetrician early in your pregnancy. Every case is different, and a personalized assessment can help you understand your options and make the safest choice for you and your baby.

Dr Najeeb Layyous F.R.C.O.G

Consultant Obstetrician, Gynecologist and Infertility Specialist