Risks of VBAC and Repeat C-Section

After publishing my article on the pros and cons (and cons) of elective cesarean, a reader asked my thoughts on VBAC, underlining the point that not all caesareans are unnecessary — some are responsible for saving the lives of babies in trouble.

Image by Getty Images via Daylife

Those considering VBAC are advised by physicians to consider carefully the risk of uterine rupture. On the other hand, there exists a wealth of statistics pointing to successful vaginal birth after cesarean.

How does one make a choice between VBAC and repeat caesarean?

Although you should certainly seek the advice of a qualified health practitioner before making any major medical decision, it’s also possible to review the medical literature and expert opinion on your own. I provide this article simply as a starting point for those who hope to make the safest choice on VBAC for both maternal and infant safety.

I cover the following topics:

• Risk/Benefit Analysis and VBAC
• Increased Risk Factors for Vaginal Birth After C-Section
• Comparing Risks of VBAC and Repeat Cesarean
• Benefits of Vaginal Delivery

Ina May Gaskin, America’s Midwife, on VBAC Safety

The first resource I turned to for an expert opinion on VBAC was Ina May Gaskin. The publication of her Spiritual Midwifery (aff) in 1975 led to her instant fame in worldwide midwifery circles. She continues today in her work as a trusted resource and activist toward safe, effective practices.

Ina May is a quintessential “hippie.” Her more recently published Ina May’s Guide to Childbirth was one of my cherished birthing books before my own successful home water birth. It was Ina who pointed me toward “potty humor” during early labor, that helped make the time fly during the first carefree phase of my labor, allowing me the energy I needed to save for the harder bits at the end!

Although I highly recommend getting your own copy of Ina May’s Guide to Childbirth (aff), especially for her Chapters on “The Pain/Pleasure Riddle,” “Sphincter Law,” “Giving Birth,” and “Forgotten Vaginal Powers,” I also wanted to share Ms. Gaskin’s thoughts on VBAC, as I feel they should be available to everyone who is beginning to weigh the pro’s and con’s of vaginal birth after cesarean. Her book contains an entire chapter with her thoughts on VBAC.

Marsden Wagner, M.D., former Director of Women’s and Children’s Health at the World Health Organization had the following to say of Ms. Gaskin and her book:

Simply put, midwife Ina May Gaskin is the most important person in maternity care in North America, bar none. As a reproductive scientist as well as a medical practitioner, I can assure readers that everything Ina May presents in this book (aff) is based on the best scientific evidence. This book should be read by every woman who is having or may someday have a baby.

For her own experience, Ms. Gaskin and midwives at The Farm Midwifery Center in Tenessee have attended successful vaginal deliveries in 98% of 115 VBAC deliveries attempted. In two cases mothers were transported to the hospital due to suspected thinning of the previous scar and the possibility of rupture. Both delivered by c-section without ruptured uterus.

This figure of successes is high compared to national averages, which have been estimated at between 60-80 percent. Ms. Gaskin attributes the high rate of success at The Farm to the fact that none of these VBAC labors were induced or augmented with oxytocin or prostaglandin.

She states:

VBAC is safe when other risk factors, such as Cyotec or other prostaglandin induction, aren’t added. The risk of uterine rupture in a woman with a previous transverse lower-uterine incision (the safest location on the uterus for incision) has always been and remains about .5 percent.

VBAC: A Risk / Benefit Analysis

When considering VBAC vs. repeat cesarean, a woman and her family need to essentially do a risk/benefit analysis of the choice before them. It’s easy to want to simplify questions of risk, especially when we want to feel good about our decision! But reality is all about risks — in fact the riskiest thing most of us do is done repeatedly throughout the week without us even thinking of the consequences: we get in our car and go for a ride.

Why do we travel in automobiles so easily when the risk of injury or death in an accident is typically the greatest risk we face? When we take a close look, we see two reasons for undergoing this daily risk:

• Firstly, for many the benefit to their chosen lifestyle outweighs the risk.
• And secondly, this risk-taking event is carried out so commonly by nearly everyone around us that we don’t even truly consider our decision to take this risk.

photo credit: johnthurm

Ultimately, we want our medical decisions to fall under the first logic, and not the second!

What are our personal values? What are the benefits that we hope to achieve in our actions? How do we see those benefits weigh in against the risks that are ultimately inherent with the act of living, breathing, and being human?

The choice between VBAC and repeat cesarean is not one of risk vs. no risk. Repeat cesarean is not a “no risk” procedure. No matter what the situation, a c-section represents major abdominal surgery and ultimately risks the life of the mother. No kidding.

So the question is simple to ask, but complicated to answer:

• Which represents the greater risk to my health and my baby’s? VBAC or repeat c-section?
• Which carries the greater benefit?
• Which combination of benefit and risk best suits my family’s values?

Increased Risk Factors for Vaginal Birth after C-Section

In this article, I will present evidence and opinions that suggest that vaginal birth after cesarean represents an overall decreased risk compared to elective repeat cesarean. These statistics refer to the majority of women have chosen to attempt VBAC deliveries.

However, there are certain cases where VBAC may carry a reduced chance of success. If these cases do apply to you, you should certainly do your own additional research. And, whether or not you fit these categories, always consult with your qualified health provider for direct medical advice.

Circumstances which may carry a reduced chance of VBAC success include:

• Women whose placenta overlies a previous uterine scar
• Women who have had more than one previous cesarean with no previous successful VBAC since (successful VBAC increases the chance of additional future successful VBACs)
• Previous classical incisions, as opposed to transverse lower-uterine incisions
• Maternal diabetes
• Use of hormones such as oxytocin for induction of labor

Factors that do not appear to increase risk of successful VBAC include:

• Large estimated birth weight
• Premature rupture of membranes (water breaking early)
• Post-date pregnancy (laboring after estimated due date)

Comparing Risks of VBAC and Repeat Cesarean: Studies and Statistics

In her book, Ina May’s Guide to Childbirth (aff), Ina May Gaskin compares the risk of vaginal birth after cesarean with repeat cesarean:

The medical evidence about VBAC is actually clearer than some recent medical and media interpretations of it would suggest. Cesarean surgery is just as risky as any other major abdominal surgery for the mother — a considerably higher risk for her than vaginal birth. With repeat cesarean she has three times the chance of dying and roughly five to ten times the risk of suffering complications. [emphasis mine]

In examining the the general risks of cesarean vs. vaginal delivery, studies have shown certain increased risks due to caesarean delivery, and other increased risks due to vaginal delivery.

General risks of cesarean delivery (those with higher risk than vaginal delivery) include:

• A threefold increase in the risk of death to the mother
• Greater risk of death to the infant, by more than double when no labor complications are present
• Increased risk of newborn respiratory problems
• A dramatic increase in the risk of hysterectomy
• Increased risk of infection and its complications
• Risk of dense adhesions, increasing the likelihood of organ injury in future abdominal or cesarean deliveries, and increasing the likelihood of bowel obstruction
• More intense and longer-lasting pain in the six months subsequent to birth
• Bladder injury
• Increased psychological problems for the mother, including difficulties in establishing breastfeeding, weakened mother-baby bonding, postpartum depression and even instances of PTSD
• Risk to babies in future pregnancies, including increased risk of pre-term delivery, low birth weight, brain and spinal cord injury, respiratory problems, and unexplained pre-term death in the womb
• Risks to future pregnancies due to accumulated cesarean scars, such as ectopic pregnancy, placenta previa and placental abruption

General risks of vaginal delivery (those with higher risks than cesarean delivery) include:

• Anal sphincter trauma
• Temporary urinary incontinence

Fewer studies are available in directly comparing specifically VBAC deliveries to repeat cesarean, however, studies appear to indicate:

• VBAC represents no additional risk to the infant,
• Repeat cesarean does however represent increased risk to the mother.

Although VBAC does represent increased risk of rupture of the uterine scar, again, this risk has not been shown to correlate with an increased overall risk of death compared with caesarean delivery.

The 2000 edition of A Guide to Effective Care in Pregnancy and Childbirth summarizes the results of existing studies nicely:

The morbidity (illness) associated with successful vaginal birth is about one-fifth that of elective cesarean. Failed trials of labour, with subsequent cesarean section, involve almost twice the morbidity of elective section, but the lower morbidity in the 80% of women who successfully give birth vaginally means that overall women who opt for a planned vaginal birth after cesarean suffer only half the morbidity of women who undergo an elective section.

In other words:

• Those who undergo c-section after a failed VBAC attempt may suffer greater complications than those who instead choose repeat cesarean.
• However this is outweighed by the fact that most women (80%) actually have success with VBAC, thus avoiding the inherent risks of cesarean. Their complications are thus significantly fewer, pointing to VBAC as the best choice for reduced complications overall, according to these authors.

Increased risks to the mother due to repeat cesarean are essentially the same set of risks due to cesarean surgery in general: risks of death, hysterectomy, surgical injury, complications from anesthesia, future ectopic pregnancies and placental complications, infertility, etc.

One group of researchers examined the change in ACOG policy favoring repeat cesarean and found no improvement in maternal or infant mortality when cesarean rates were increased for those having delivered previously by cesarean. If planned repeat cesarean were actually safer, presumably infant and maternal death rates would be reduced once more women began undergoing elective repeat cesarean; they were not.

Neonatal and maternal mortality rates did not improve despite increasing rates of repeat cesarean delivery during the years after the ACOG 1999 VBAC guideline revision. Women with infants weighing ≥1,500 g encountered similar neonatal and maternal mortality rates with VBAC or repeat cesarean delivery. (Zweifler, Garza et al, Annals of Family Medicine)

Increased Medico-Legal Risk of VBAC

Clearly there must be some increased risk involved in VBAC delivery, considering that mothers who have had previous cesareans are now routinely advised against attempting vaginal delivery.

Although the American College of Obstetricians and Gynecologists (ACOG) recommended limiting repeat cesarean births to those medically necessary beginning in the late 1980’s, they reversed this recommendation in 1998, currently recommending that VBAC be attempted only under a specific set of situations and protections offered by a small set of hospitals nationwide. This has, correspondingly, led to an overwhelming majority of planned cesarean deliveries following previous cesarean births.

Ina May Gaskin explains the reason for this change in recommendation, and unveils the nature of risk involved. The increased risk of VBAC appears not to be risk to the mother or baby, but in fact a risk to the doctor. Because cesarean delivery is considered an act of precaution in the legal system, doctors who deliberately choose cesarean are seen as taking protective action against harm, and are thus invulnerable to the financial risk of lawsuit.

Whereas the 1995 ACOG bulletin reads like a scientific article meant to persuade, the 1998 and 1999 bulletins are full of unfounded assertions and heavy implications. For example, ‘Reports indicate that maternal and infant complications also are associated with an unsuccessful trial of labor. Increasingly, these adverse events during trial of labor have led to malpractice suits.’ No references are provided for the statement about maternal and infant complications, because no studies support it. The statement about malpractice suits, however, is given three citations. — Ina May’s Guide to Childbirth

Benefits of Vaginal Delivery

Scientists are truly still discovering the benefits of vaginal delivery compared to cesarean delivery. Why? The entire human system has evolved over time with neurochemistry, hormones, and all of the body’s systems working together to promote the safest, most effective delivery for mother and baby, while simultaneously promoting bonding through our bodies emotional, libidinal systems. This harmony was designed in all mammals to promote survival of mother and her young.

When we introduce an alternate means of delivery, we tamper with this system’s existing mechanisms, the result of which is still under investigation. It is these differences that have so far been found accountable for reduced mother-baby bonding and increased postpartum depression. That is not to say that women who birth by cesarean cannot bond with their babies, or inevitably experience postpartum depression! It simply means that, as her hormonal and neurological systems are somewhat disabled, these things are more difficult for mother to achieve with ease.

photo credit: marathonpix

What other benefits does natural (un-sedated) vaginal delivery hold?

One excellent list of the benefits can be found at Natural-Childbirth.net. For me, it was a personal high. One that is also attributable to natural chemical interactions in the body! Any athlete will tell you there is nothing like the high of pushing the body to work miracles and beat records. The high of natural childbirth is much like these accomplishments. Hormones secreted during natural vaginal delivery are also similar to those found in couples when they fall in love!

Is the physical intensity of natural childbirth worth the experience of these kinds of physiological highs — falling in love, running a marathon? Many moms say yes! If you’re interested in attempting natural childbirth a second time, these benefits may be worth some measure of risk.

Only you and your care provider can make the decision as to whether the potential risks of vaginal birth after cesarean outweigh the potential risks of repeat caesarean.

I hope that exploring the links throughout this article will provide you some thought provoking considerations and a set of statistics to help back you up in your decisions. I’d like to follow up this post with one outlining some of Ina May Gaskin and others’ suggestions to help improve your chances of successful VBAC, should you choose to take that route. The same information is available in Ina May’s Guide to Childbirth and HypnoBirthing: The Mongan Method (aff).

No matter what choice you and your family make, make sure that you choose a health provider with a solid quantifiable history of success with your chosen method of delivery, VBAC or cesarean, and whose philosophies match yours well. Consult with them fully as to how your previous medical history fits with VBAC and/or surgical cesarean delivery. We each have a unique medial history, and no statistics can tell the outcome for the individual. The success of your delivery is truly a team project!

Good luck to you!

Love,

Mama Hope

Disclaimer: The above content is for informational purposes only and is not intended to give medical advice. This content not intended as a substitute for professional advice, diagnosis, or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional advice or delay in seeking it because of content found on this site.

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