Category Archives: Medical Studies

New Research on Home Birth with an Obstetrician

male-doctor-thumbs-up-squareOver the last five years Dr. Stuart Fischbein, a Southern California obstetrician, has attended 135 home births. These deliveries included VBACs, vaginal breech and vaginal twin deliveries.

A summary of these births has been recently published.

Here are some highlights along with a few additional resources I compiled where you can learn more.

On patient selection:

“This model was not limited by strict protocols and allowed for guidelines to be merely guidelines. Women over 35, VBAC, breech and twin pregnancies were not excluded from this series simply because those labels existed. Each client was evaluated on her own merits and the comfort of the practitioner.”

On informed choice and the limitations of hospital birth:

“Home birth is not for everyone but informed choice is. The patronizing statement, “home delivery is for pizza”, is unprofessional and has no place in the legitimate discussion. Some suggest making hospital birth more homelike. While this may be a beginning and deserves investigation, it fails to recognize the difficult balance between honoring normal undisturbed mammalian birth and the reality of the hospital model’s legal and economic concerns and policies.”

On collaborative care:

“Pregnant women deserve to know that midwifery style care, both in and out of hospital, is a reasonable choice. A collaborative model between obstetrician and midwife can provide better results than what is occurring today.”

On lost skills:

“It would be wise to put the constructive energy of our profession towards the training of future practitioners in the skills that make obstetricians truly specialists such as breech, twin and operative vaginal deliveries.”

On the growth of home birth:

“Home birth will continue to grow as educated women realize that the current hospital model has many flaws.”

On our ethical obligation to provide a smooth home to hospital transfer:

“Cooperation, respect and smooth transition from home to hospital honors the pregnant woman and is our ethical obligation.”

_____________

California Healthcare Foundation. (2014, Nov). A Tale of Two Births: High- and Low-Performing Hospitals on Maternity Measures in California. Retrieved from California Healthcare Foundation: http://www.chcf.org/publications/2014/11/tale-two-births

Fischbein SJ (2015) “Home Birth” with an Obstetrician: A Series of 135 Out of Hospital Births. Obstet Gynecol Int J 2(4): 00046. DOI: 10.15406/ogij.2015.02.00046. Retrieved from Obstetrics & Gynecology International Journal: http://medcraveonline.com/OGIJ/OGIJ-02-00046.pdf

Johnson, N. (2010, Sept 11). For-profit hospitals performing more C-sections. Retrieved from California Watch: http://californiawatch.org/health-and-welfare/profit-hospitals-performing-more-c-sections-4069

Kennedy, M. (Director). (2015). Heads Up! The Disappearing Art of Vaginal Breech Delivery [Motion Picture]. Retrieved from http://www.informedpregnancy.com/#!heads-up/cef1

Klagholz, J., & Strunk, A. (2012). Overview of the 2012 ACOG Survey on Professional Liability. Retrieved from The American Congress of Obstetricians and Gynecologists: http://www.acog.org/-/media/Departments/Professional-Liability/2012PLSurveyNational.pdf

The term “trial of labor after cesarean” is actually really important

On the acronym TOLAC (trial of labor after cesarean)….

Some studies break out statistics in four ways.

1. ERCS/D (elective repeat cesarean section/ delivery)
2. VBAC (vaginal birth after cesarean)
3. CBAC (cesarean birth after cesarean aka cesarean after planned VBAC)
4. TOLAC (VBAC + CBAC stats)

Because we are unable to predict who will have a VBAC or CBAC, the TOLAC stat enables us to review outcomes from a variety of angles:

  • TOLAC vs. ERCS
  • VBAC vs. ERCS
  • CBAC vs. ERCS

Some women find the TOLAC acronym offensive, because it implies “trying,” so practitioners sensitive to this may way to use the phrase “planning a VBAC.”   Understanding that TOLAC isn’t a dig at moms, but just a straightforward, objective term that care providers use, can (hopefully) take the sting out of the word.

Remember, your care provider is not your girlfriend.  They use clinical terms because that is the language of their world. They speak like clinicians because they are clinicians. All that said, providers who are aware of how the term TOLAC is received by some women use the term “planned VBAC.”

So moms, you use the language that works for you! Just remember that TOLAC is really more of a clinical term and when your provider uses it, it doesn’t necessarily mean that they are a jerk.  They just may have forgotten to code switch from clinical to sensitive language.

Moms don’t typically say, “I’m so excited for my TOLAC!” However, if you do, you might make your provider laugh and connect with them on a human level.

Two points for the person who knows how this picture is relevant…

20120808-102648.jpg

Just kicking the can of risk down the road

This is why cesareans should not be casual or performed for the convenience of anyone.  They should be reserved for real medical reasons so that the benefits of having the cesarean outweigh the risks.  And there are real risks to cesareans, but since the ones list below are future risks, they may seem less real.  Per a November 2011 study published in the Journal of Maternal-Fetal and Neonatal Medicine:

If primary and secondary cesarean rates continue to rise as they have in recent years, by 2020 the cesarean delivery rate will be 56.2%, and there will be an additional 6236 placenta previas, 4504 placenta accretas, and 130 maternal deaths annually. The rise in these complications will lag behind the rise in cesareans by approximately 6 years.

Placenta previa and accreta are nothing to mess around with.  Accreta in particular has a very high maternal mortality rate and many mothers end up having cesarean hysterectomies.   I write more about accreta here.

Many women do not think these complications are applicable to them as they don’t plan on more children after their two cesareans.  But I know many women, and I’m sure you do too, who were not planning on more children, but got pregnant nonetheless.  Unless you or your partner get sterilized or practice abstinence (what fun!), the chance of you getting pregnant is there.

By performing routine scheduled repeat cesareans, we do reduce the risk of uterine rupture in the current pregnancy, but we are also increasing the risks of accreta, previa, maternal death as well as uterine rupture in future pregnancies.  In addition, another large study found

[t]he risks of placenta accreta, cystotomy [surgical incision of the urinary bladder], bowel injury, ureteral [ureters are muscular ducts that propel urine from the kidneys to the urinary bladder] injury, and ileus [disruption of the normal propulsive gastrointestinal motor activity], the need for postoperative ventilation, intensive care unit admission, hysterectomy, and blood transfusion requiring 4 or more units, and the duration of operative time and hospital stay significantly increased with increasing number of cesarean deliveries.

And this is especially relevant in rural hospitals which institute VBAC bans because they don’t offer 24/7 anesthesia.  Even though the “immediately available” clause was removed in the latest (2010) ACOG VBAC Practice Bulletin, many of these bans still stand.

However, in order to rapidly respond to the potentially sudden diagnosis of accreta, previa, or abruption, the hospital will have to enact many of the same ideas provided at the 2010 NIH VBAC Conference on how a hospital without 24/7 anesthesia can safely offer VBAC and respond to uterine rupture.  So why not just institute those ideas from the get-go and offer VBAC to those who want it?  (I know, I know: medico-legal reasons, which the NIH also addressed, but that is another post.)  From VBAC Ban Rationale is Irrational:

 As David J. Birnbach, M.D., M.P.H (2010), who presented on the impact of anesthesiologists on the incidence of VBAC [at the 2010 NIH VBAC Conference] asserted:

Lack of immediate available of anesthesia may not always be a key factor in outcome [during a uterine rupture], especially in cases where the obstetrician is not present. Many cases of uterine rupture can be stabilized while the anesthesiologists becomes available, and examples have been suggested of ways to reduce the risk associated with such a crisis. These include antepartum [prenatal] consultation of VBAC patients with the anesthesia departments, development of cesarean delivery under local anesthesia protocols, finding methods of improving communication on labor and delivery suites, practice “fire-drills,” and development of protocols matching resources to risk.

I urge you to watch Dr. Birnbach’s presentation along with all the presentations from the 2010 NIH VBAC conference.

Read more about the how the risk of serious complications increase with each cesarean surgery.

Below is Silver’s (2006) study abstract:

J Matern Fetal Neonatal Med. 2011 Nov;24(11):1341-6. Epub 2011 Mar 7.

The effect of cesarean delivery rates on the future incidence of placenta previa, placenta accreta, and maternal mortality.

Solheim KN, Esakoff TF, Little SE, Cheng YW, Sparks TN, Caughey AB. Source Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, CA, USA. Abstract

OBJECTIVE: The overall annual incidence rate of caesarean delivery in the United States has been steadily rising since 1996, reaching 32.9% in 2009. Primary cesareans often lead to repeat cesareans, which may lead to placenta previa and placenta accreta. This study’s goal was to forecast the effect of rising primary and secondary cesarean rates on annual incidence of placenta previa, placenta accreta, and maternal mortality.

METHODS: A decision-analytic model was built using TreeAge Pro software to estimate the future annual incidence of placenta previa, placenta accreta, and maternal mortality using data on national birthing order trends and cesarean and vaginal birth after cesarean rates. Baseline assumptions were derived from the literature, including the likelihood of previa and accreta among women with multiple previous cesarean deliveries.

RESULTS: If primary and secondary cesarean rates continue to rise as they have in recent years, by 2020 the cesarean delivery rate will be 56.2%, and there will be an additional 6236 placenta previas, 4504 placenta accretas, and 130 maternal deaths annually. The rise in these complications will lag behind the rise in cesareans by approximately 6 years.

CONCLUSIONS: If cesarean rates continue to increase, the annual incidence of placenta previa, placenta accreta, and maternal death will also rise substantially.

http://www.ncbi.nlm.nih.gov/pubmed/21381881

Cerebral palsy cases linked with genetic abnormalities

Conventional wisdom has historically linked oxygen deprivation during labor and delivery to cerebral palsy (CP), but a new study suggests that the majority of CP cases are actually due to genetic abnormalities in at least six genes.

A Medical News Today article dated January 30, 2012 discusses the study published in The Lancet Neurology:

Although there has been considerable improvements in neonatal and obstetric care for over 4 decades, the global prevalence of CP has remained stable at 2-3 per 1,000 live births.

. . .

David Ledbetter, Ph.D., chief scientific officer, Geisinger Health System, said:

“What we’re finding is that even though more preventative efforts have been put in place like fetal monitoring, the incidence of CP has not decreased. We’ve seen a five-fold increase in the rate of caesarean sections, which are doing in part to avoid potentially difficult delivery, and again, the CP rates remain steady. These findings lead us to believe genetics play a much bigger role than previously thought.”

. . .

Dr. Andres Moreno De Luca, M.D., research scientist at the Genomic Medicine Institute, Geisinger Health System, and lead research of the study, explains:

“We now know of six genes that can cause CP when disrupted, and we estimate that many other developmental brain genes probably contribute to the genetic heterogeneity of this disorder.”

This is consistent with the National Institute of Neurological Disorders and Stroke, National Institute of Health webpage “Cerebral Palsy: Hope Through Research” last updated November 4, 2011:

The majority of children with cerebral palsy are born with it, although it may not be detected until months or years later.  This is called congenital cerebral palsy.  In the past, if doctors couldn’t identify another cause, they attributed most cases of congenital cerebral palsy to problems or complications during labor that caused asphyxia (a lack of oxygen) during birth.  However, extensive research by NINDS scientists and others has shown that few babies who experience asphyxia during birth grow up to have cerebral palsy or any other neurological disorder. Birth complications, including asphyxia, are now estimated to account for only 5 to 10 percent of the babies born with congenital cerebral palsy.

The National Institute of Neurological Disorders and Stroke defines cerebral palsy as, “any one of a number of neurological disorders that appear in infancy or early childhood and permanently affect body movement and muscle coordination but aren’t progressive, in other words, they don’t get worse over time. ”  Read more here.

Study finds vernix protects newborns from infection

There is a reason why vernix is present. Read below for some very technical language which essentially says vernix protects newborns from fungi, parasites, and makes pathogens susceptible to our immune system.  In other words, vernix protects newborns from infection which is why it is beneficial to not wash your baby and scrub away all that vernix, immediately after birth.

Published in the journal “Cellular and Molecular Life Sciences,” “Vernix caseosa as a multi-component defence system based on polypeptides, lipids, and their interactions” found:

Vernix caseosa is a white cream-like substance that covers the skin of the foetus and the newborn baby. Recently, we discovered antimicrobial peptides/proteins such as LL-37 in vernix, suggesting host defence functions of vernix. In a proteomic approach, we have continued to characterize proteins in vernix and have identified 20 proteins, plus additional variant forms. The novel proteins identified, considered to be involved in host defence, are cystatin A, UGRP-1, and calgranulin A, B and C. These proteins add protective functions to vernix such as antifungal activity, opsonizing capacity, protease inhibition, and parasite inactivation. The composition of the lipids in vernix has also been characterized and among these compounds the free fatty acids were found to exhibit antimicrobial activity. Interestingly, the vernix lipids enhance the antimicrobial activity of LL-37 in vitro, indicating interactions between lipids and antimicrobial peptides in vernix. In conclusion, vernix is a balanced cream of compounds involved in host defence, protecting the foetus and newborn against infection.

definition decision

Studies find pregnant women with prior cesarean choose the delivery method preferred by their doctor

Update: Metz (2013) came to the same conclusion of Bernstein (2012).  Metz concluded, “Less than one third of the good candidates for TOLAC [trial of labor after cesarean] chose TOLAC. Managing provider influences this decision.”  Read more here.

______________________________

The findings of “Trial of labor after previous cesarean section versus repeat cesarean section: are patients making an informed decision?” presented at the February 9, 2012 annual meeting of the Society for Maternal-Fetal Medicine’s, The Pregnancy Meeting ™, in Dallas, Texas is not surprising.  Doctors have so much influence over patients and apparently, patients are making medical decisions without a basic understanding the benefits and risks of their options.

“Even though most women can achieve a vaginal delivery with trial of labor, less than 10 percent of them attempt to do so,” said Sarah Bernstein, MD, with St. Luke’s-Roosevelt Hospital Center, Obstetrics and Gynecology, in New York, and one of the study’s authors. “In fact, when patients perceived that their doctor preferred a repeat cesarean, very few chose to undergo trial of labor, whereas the majority chose trial of labor if that was their doctor’s preference.”

The study was a survey provided to women upon admission for their elective repeat cesarean section (ERCS) or trial of labor after cesarean section (TOLAC).  I am really shocked at the level of knowledge most of the women had. 73% of the women admitted for a ERCS did not know the chances of a successful VBAC and 64% did not know the risk of uterine rupture.  54% of women choosing a TOLAC did not know the chances of a successful VBAC and 45% did not know the risk of rupture!  WOW!!

Women in both groups demonstrated lack of knowledge on the risks and benefits of TOLAC and ERCS, particularly women in the ERCS group. Specifically, patients were not familiar with the chances of a successful TOLAC, the effect of indication for previous CS on success, the risk of uterine rupture, and the increase in risk with each successive CS.  Only 13% of TOLAC patients and 4% of ERCS patients knew the chances for a successful TOLAC, while the majority in both groups stated that they “did not know”.  The majority (64%)of ERCS patients did not know the risk of uterine rupture during TOLAC and 52% did not know which delivery mode had a faster recovery time.

This is why, even if you are on the fence about VBAC vs. repeat cesarean, selecting a care provider who is genuinely supportive of VBAC gives you the power of choice.  Read more on what makes a supportive care provider here.

Read the press release and a news article.  The abstract is available on page 3 of this PDF.

Quickly and easily provide the resources for VBAC information with the FAQ card.

Sources

Bernstein, S., Matalon-Grazi, S., & Rosenn, B. (2012). Trial of labor after previous cesarean section versus repeat cesarean section: are patients making an informed decision? Supplement to JANUARY 2012 American Journal of Obstetrics & Gynecology, S21. Retrieved from http://www.smfmnewsroom.org/wp-content/uploads/2012/01/Abstracts-27-35.pdf

Study: Two-Thirds of OB-GYN Clinical Guidelines Have No Basis in Science

PushNews from The Big Push for Midwives Campaign
CONTACT: Katherine Prown, (414) 550-8025, katie@pushformidwives.org
FOR IMMEDIATE RELEASE: August 15, 2011
Study: Two-Thirds of OB-GYN Clinical Guidelines Have No Basis in Science
Majority of ACOG Recommendations for Patient Care Found to Be Based on Opinion and Inconsistent Evidence
WASHINGTON, D.C. (August 15, 2011)—A study published this month in Obstetrics & Gynecology, the journal of the American College of Obstetricians and Gynecologists, found that barely one-third of the organization’s clinical guidelines for OB/GYN practice meet the Level A standard of “good and consistent scientific evidence.” The authors of the study found instead that the majority of ACOG recommendations for patient care rank at Levels B and C, based on research that relies on “limited or inconsistent evidence” and on “expert opinion,” both of which are known to be inadequate predictors of safety or efficacy.

“The fact that so few of the guidelines that govern routine OB/GYN care in this country are supported by solid scientific evidence—and worse, are far more likely to be based on anecdote and opinion—is a sobering reminder that our maternity care system is in urgent need of reform,” said Katherine Prown, PhD, Campaign Manager of The Big Push for Midwives. “As the authors of the study remind us, guidelines are only as good as the evidence that supports them.”

ACOG Practice Bulletin No. 22 on the management of fetal macrosomia—infants weighing roughly 8 ½ lbs or more at birth—illustrates the possible risks to mothers and babies of relying on unscientific clinical guidelines. The only Level A evidence-based recommendation on the delivery of large-sized babies the Bulletin makes is to caution providers that the methods for detection are imprecise and unreliable. Yet at the same time, the Bulletin makes a Level C opinion-based recommendation that, despite the lack of a reliable diagnosis, women with “suspected” large babies should be offered potentially unnecessary cesarean sections as a precaution, putting mothers at risk of surgical complications and babies at risk of being born too early.

“It’s no wonder that the cesarean rate is going through the roof and women are seeking alternatives to hospital-based OB/GYN care in unprecedented numbers,” said Susan M. Jenkins, Legal Counsel of The Big Push for Midwives. “ACOG’s very own recommendations give its members permission to follow opinion-based practice guidelines that have far more to do with avoiding litigation than with adhering to scientific, evidence-based principles about what’s best for mothers and babies.”

The Big Push for Midwives Campaign represents tens of thousands of grassroots advocates in the United States who support expanding access to Certified Professional Midwives and out-of-hospital maternity care. The mission of The Big Push for Midwives is to educate state and national policymakers and the general public about the reduced costs and improved outcomes associated with out-of-hospital maternity care and to advocate for expanding access to the services of Certified Professional Midwives, who are specially trained to provide it.

Media inquiries: Katherine Prown (414) 550-8025, katie@pushformidwives.org

Shows the rates of placenta accreta in up to six cesareans (Silver 2006).

Risk of serious complications increase with each cesarean surgery

Yesterday I shared a Canadian article, and last year a letter from two OBs opposing a hospital VBAC ban, which discuss the risks of cesarean sections including placenta accreta and hysterectomy.

Definitions

Today I want to share a study that measured the increasing risks that come with multiple cesareans, but before I do so, lets do a quick review of definitions.

Placenta accreta (March of Dimes 2005):

In a normal pregnancy, the placenta attaches itself to the uterine wall, away from the cervix.

  • Placenta accreta is a placenta that attaches itself too deeply and too firmly into the wall of the uterus.
  • Placenta increta is a placenta that attaches itself even more deeply into the uterine wall.
  • Placenta percreta is a placenta that attaches itself through the uterus, sometimes extending to nearby organs, such as the bladder.

Hysterectomy (Women’s Health 2009):

A hysterectomy (his-tur-EK-tuh-mee) is a surgery to remove a woman’s uterus or womb. The uterus is where a baby grows when a woman is pregnant. The whole uterus or just part of it may be removed. After a hysterectomy, you no longer have menstrual periods and cannot become pregnant.

Placenta previa (PubMedHealth 2011):

Placenta previa is a complication of pregnancy in which the placenta grows in the lowest part of the womb (uterus) and covers all or part of the opening to the cervix.

There are different forms of placenta previa:

  • Marginal: The placenta is next to cervix but does not cover the opening.
  • Partial: The placenta covers part of the cervical opening.
  • Complete: The placenta covers all of the cervical opening.

Increasing risks with multiple cesareans: Focusing on accreta

Today’s study is Maternal morbidity associated with multiple repeat cesarean deliveries (Silver 2006) which included over 30,000 women undergoing up to six cesareans over four years.  (Download the full text PDF.)  Silver measured the complication rates per cesarean number.  And their findings are important to every mom pregnant after a cesarean.  Keep in mind that all the cesareans included in the Silver (2006) study were schedule and performed without medical indication except for the first cesarean.  All the complications noted were a direct result of the surgery, not of any other medical complication.

Silver (2006) found:

The risks of placenta accreta, cystotomy [surgical incision of the urinary bladder], bowel injury, ureteral [ureters are muscular ducts that propel urine from the kidneys to the urinary bladder] injury, and ileus [disruption of the normal propulsive gastrointestinal motor activity], the need for postoperative ventilation, intensive care unit admission, hysterectomy, and blood transfusion requiring 4 or more units, and the duration of operative time and hospital stay significantly increased with increasing number of cesarean deliveries.

Accreta was defined as the “placenta being adherent to the uterine wall without easy separation [and] included placenta accreta, increta, and percreta.”

Below are some slides from the VBAC Class I developed and teach illustrating the  rates of placenta accreta, previa, previa with accreta, and hysterectomy by number of cesareans (Silver 2006).   The number below the cesarean number indicate how many women were included in that category.

Remember as you look these over, the risk of uterine rupture in a spontaneous labor after one prior low horizontal (“bikini-cut”) cesarean is 0.4% (Landon 2004).  Risk of uterine rupture during one’s second cesarean is 0.9% (Landon 2006).

Shows the rates of placenta accreta in up to six cesareans (Silver 2006).

 Shows the rate of placenta previa by cesarean number (Silver 2006).

Accreta, previa, and cesarean hysterectomies

I was especially interested to see the relationship between previa and accreta.  Silver (2006) found that if you have previa, you are very likely to have accreta and that risk increases with each cesarean.  For example, if a woman has one cesarean and is diagnosed with previa in her next pregnancy, her risk of having accreta is 11%.  That risk jumps to 40% in the third pregnancy, 61% in the fourth pregnancy and 67% for the fifth and sixth pregnancy.

Shows the rate of placenta previa with accreta per Silver 2006.

Complications associated with accreta

Accreta is nothing to mess around with as it has a very high rate of maternal mortality (up to 7%) and morbidity including hemorrhage and hysterectomy.  Fang (2006) asserted, “abnormal adherent placentation [is] the primary indication leading to emergent peripartum hysterectomy…. As the number of prior cesarean deliveries rises, the risk of cesarean hysterectomy increases dramatically.”   In other words, all these primary cesareans and repeat cesareans are causing placentas to abnormally implant in subsequent pregnancies.  As a result, many women who have placenta accreta end up having hysterectomies as that is the best way to control the hemorrhaging that results from accreta.

Rate of hysterectomy by cesarean number (Silver 2006).

Women who had accreta also experienced the following complications:

  • 15.4% (1 in 6.5): surgical injury to bladder
  • 2.1%  (1 in 48): surgical injury to the ureters which are the tubes that connect the kidneys to the bladder and is the “most serious complication of gynecologic surgery
  • 2.1%  (1 in 48 ): blockage of an artery in the lungs (pulmonary embolism)
  • 14% (1 in 7):  mom was put on a mechanical ventilator because she couldn’t breathe effectively
  • 26.6% (1 in 3.8): mom requires advanced monitoring and care so she is admitted to the intensive care unit
  • 5.6% (1 in 17.8): mom requires another operation
  • 3.5% (1 in 28.6): endometritis, “an inflammation or irritation of the lining of the uterus”

Because the risks of cesarean are so great, Silver (2006) concluded with the following statement,

Because serious maternal morbidity increases progressively with increasing number of cesarean deliveries, the number of intended pregnancies should be considered during counseling regarding elective repeat cesarean operation versus a trial of labor and when debating the merits of elective primary cesarean delivery.

Alternatives to cesarean hysterectomy

Non-hysterectomy options were discussed in a February 2006 Healthline article by Alison Stuebe, Department of Maternal-Fetal Medicine, Brigham and Women’s Hospital, Boston, MA:

In the majority of cases, hysterectomy is the most effective way to manage the potentially fatal consequences of placenta accreta. Unfortunately, however, most cases of placenta accreta are not discovered until the last minute. And, because a hysterectomy results in infertility, some women may want to consider more conservative options.

Conservative or alternate techniques for treating placenta accreta include:

  • curettage (scraping) of the uterus;
  • surgical repair of the part of the uterus where the placenta was attached;
  • clamping the blood vessels that nourish the pelvis (to control the bleeding); and
  • using x-ray guidance to inject gelatin sponge particles or spring coils into the blood vessels that nourish the uterus (this procedure usually is not feasible in emergency situations.) This procedure requires help from interventional radiologists, doctors who specialize in advanced treatments for bleeding.

Reported success rates of these procedures vary widely. In one recent study, 31 cases of placenta accreta were managed without hysterectomy; there were no reports of infertility or maternal death.

Using ultrasound and MRI to diagnose accreta

All the statistics I have shared above are from hospital based studies where women have access to operating rooms, surgeons, and blood products.  I suspect that the likelihood of a mother dying from hemorrhage due to placenta accreta is significantly higher in an OOH (out-of-hospital) birth.  This is why I think it is completely reasonable to have an ultrasound or MRI to try to diagnose accreta when planning a OOH birth.

Although second and third trimester bleeding can be a symptom for previa, I was surprised to read on the University of Maryland Medical Center’s website, “About 7% to 30% of women with placenta previa do not experience vaginal bleeding as a symptom before delivery.”   Thus one cannot rely on bleeding during pregnancy as a reliable symptom for previa which is why ruling it out via ultrasound appears to be a effective plan. (No citation was given, so if anyone has information to affirm or refute this stat, please leave a comment.)

There appears to be some controversy about the ability to accurately diagnose accreta during pregnancy.  According to a 2011 Medscape article byDr. Robert Resnik, “the diagnosis [of placenta accreta] can be made with accuracy, by very specific ultrasound findings, about 80% of the time, and can be confirmed with MRI findings.”

However, in a 2010 article published in the Journal Watch Women’s Health, Andrew M. Kaunitz, MD states, “If ultrasound findings [while looking for accreta] are not definitive, MRI evaluation is appropriate.  Unfortunately, the diagnostic precision of these two imaging modalities for placenta accreta can be suboptimal.”

I also highly recommend you read Dwyer (2008) which provides an excellent overview and compared the accuracy of the two methods:

Sonography correctly identified the presence of placenta accreta in 14 of 15 patients (93% sensitivity) and the absence of placenta accreta in 12 of 17 patients (71% specificity). Magnetic resonance imaging correctly identified the presence of placenta accreta in 12 of 15 patients (80% sensitivity) and the absence of placenta accreta in 11 of 17 patients (65% specificity). In 7 of 32 cases, sonography and MRI had discordant diagnoses: sonography was correct in 5 cases, and MRI was correct in 2.

Because of this high rate of maternal mortality and morbidity, some doctors suggest if accreta is diagnosed via ultrasound and/or magnetic resonance imaging (MRI) during pregnancy, a cesarean hysterectomy should to performed as early as 34 – 35 weeks.  (Read Does Antenatal Diagnosis of Placenta Accreta Improve Maternal Outcomes?, The maternal outcome in placenta accreta: the significance of antenatal diagnosis and non-separation of placenta at delivery and Placenta accreta: A dreaded and increasing complication for more information on early delivery via cesarean section.)

What difference does it make if you know you have accreta before delivery?

Because accreta has a high maternal mortality and morbidity rate, a hospital plans for a birth with accreta (usually a cesarean if diagnosed before labor) very differently than a birth (cesarean or vaginal) without known accreta.

One night during my endless random reading, I stumbled across the Royal College of Obstetricians and Gynaecologists’ (the UK’s ACOG) clinical guidelines for placenta praevia, placenta praevia accreta and vasa praevia.  (Note that the Brits do spell previa/praevia differently than Americans.)  This document included a detailed description of how they recommend a hospital plan for a cesarean birth due to placenta accreta:

The six elements considered to be reflective of good care were:
1. consultant obstetrician planned and directly supervising delivery
2. consultant anaesthetist planned and directly supervising anaesthetic at delivery
3. blood and blood products available
4. multidisciplinary involvement in pre-op planning
5. discussion and consent includes possible interventions (such as hysterectomy, leaving the placenta in place, cell salvage and intervention radiology)
6. local availability of a level 2 critical care bed.

Taking this extensive preparation into account, I suspect that women fare better when accreta is diagnosed before delivery.

Evidence to suggest previa less likely to “move” in VBAC/VBAMC moms

RCOG’s clinical guidelines also included evidence that of women who were diagnosed with previa early in their pregnancy, women with a prior cesarean where less likely than an unscarred mom to have their placenta “move” enough to permit a vaginal delivery at term (50% vs. 11%).  Since the study in question included over 700 women with previa, this is a large enough study to give us good evidence.

Women with a previous caesarean section require a higher index of suspicion as there are two problems to exclude: placenta praevia and placenta accreta.  If the placenta lies anteriorly and reaches the cervical os at 20 weeks, a follow-up scan can help identify if it is implanted into the caesarean section scar.

Placental ‘apparent’ migration, owing to the development of the lower uterine segment, occurs during the second and third trimesters,52–54 but is less likely to occur if the placenta is posterior55 or if there has been a previous caesarean section.35  In one study, only five of 55 women with a placenta reaching or overlapping the cervical os at 18–23 weeks of gestation (diagnosed by TVS) had placenta praevia at birth and in all cases the edge of the placenta had overlapped 15 mm over the os at 20 weeks of gestation.56  A previous caesarean section influences this: a large retrospective review of 714 women with placenta praevia found that even with a partial ‘praevia’ at 20–23 weeks (i.e. the edge of the placenta reached the internal cervical os), the chance of persistence of the placenta praevia requiring abdominal delivery was 50% in women with a previous caesarean section compared with 11% in those with no uterine scar.53

Conversely, although significant migration to allow vaginal delivery is unlikely if the placenta substantially overlaps the internal os (by over 23 mm at 11–14 weeks of gestation in one study,54 by over 25 mm at 20–23 weeks of gestation in another52 and by over 20 mm at 26 weeks of gestation in a third study57), such migration is still possible and therefore follow-up scanning should be arranged.

I looked up source 53 and it’s Dashe (2002) which shared:  “The outcome of the study was persistent placenta previa resulting in cesarean delivery.  This diagnosis was based on clinical assessment and ultrasound at time of delivery.”  You can read Dashe in its entirety by clicking on this link and then looking for the “Article as PDF” link on the right hand side.

Considering your future fertility

Many women who don’t plan on having more children do not think these complications are applicable.  But I know many women, and I’m sure you do too, who were not planning on more children, but got pregnant nonetheless.  This is consistent with the CDC’s findings that 49% of pregnancies are unintentional.  Unless you or your partner get sterilized or practice abstinence (what fun!), the chance of you getting pregnant, and experiencing these downstream risks, are there.  It’s important when evaluating your current birth options to consider how that decision will impact the risks of your future pregnancies as well as your future delivery options.

Last updated 9/13/12.

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Uterine rupture risk drops significantly after first VBAC

As we know, the risks of cesareans increase with each surgery which is why family size should be considered when evaluating your post-cesarean birth options. Couple that fact with the results of Mercer (2008) which found that successful VBAC also provides a level of protection to future deliveries.

Mercer found that not only do the risks of uterine rupture, uterine dehiscence and other peripartum complications decrease after the first VBAC, but “VBAC success increased with increasing number of prior VBACs” to rates over 90% for women with two or more prior VBACs.  They also found that while two or more VBACs did not decrease the risk of rupture further (so a scarred mom’s risk of rupture never goes down to the risk of an unscarred mom), it’s important to note that the risk of rupture did not increase with subsequent VBACs as women are sometimes told in an effort to obtain their consent for a repeat cesarean.

Read the abstract below, link to the study abstract, or read the full text.

This is one of many studies that the journal Obstetrics & Gynecology provides to the public, full-text, for free without registration.


Mercer, B. M., Gilbert, S., Landon, M. B., & Spong, C. Y. (2008). Labor Outcomes With Increasing Number of Prior Vaginal Births After Cesarean Delivery. Obstetrics & Gynecology , 11, 285-91. Retrieved from http://journals.lww.com/greenjournal/Fulltext/2008/02000/Labor_Outcomes_With_Increasing_Number_of_Prior.6.aspx

ABSTRACT

OBJECTIVE: To estimate the success rates and risks of an attemptedvaginal birth after cesarean delivery (VBAC) according to thenumber of prior successful VBACs.

METHODS: From a prospective multicenter registry collectedat 19 clinical centers from 1999 to 2002, we selected womenwith one or more prior low transverse cesarean deliveries whoattempted a VBAC in the current pregnancy. Outcomes were comparedaccording to the number of prior VBAC attempts subsequent tothe last cesarean delivery.

RESULTS: Among 13,532 women meeting eligibility criteria, VBACsuccess increased with increasing number of prior VBACs: 63.3%,87.6%, 90.9%, 90.6%, and 91.6% for those with 0, 1, 2, 3, and4 or more prior VBACs, respectively (P uterine rupture decreased after the first successful VBAC anddid not increase thereafter: 0.87%, 0.45%, 0.38%, 0.54%, 0.52%(P=.03). The risk of uterine dehiscence and other peripartumcomplications also declined statistically after the first successfulVBAC. No increase in neonatal morbidities was seen with increasingVBAC number thereafter.

CONCLUSION: Women with prior successful VBAC attempts are atlow risk for maternal and neonatal complications during subsequentVBAC attempts. An increasing number of prior VBACs is associatedwith a greater probability of VBAC success, as well as a lowerrisk of uterine rupture and perinatal complications in the currentpregnancy.

LEVEL OF EVIDENCE: II

Cesarean Risks: Overview

We all know the primary risk of VBAC – uterine rupture.  And when your typical VBACing mom meets with an OB, she must sign a “VBAC consent form” acknowledging that she understands this risk.  However, I find it ironic that women signing up for a repeat cesarean are not required by their OB to sign a “Repeat Cesarean Section consent form” as a matter of course during prenatal exams since there are risks associated with cesarean section.   But since this does not happen, and most OBs breeze over the risks if they even bother to mention them, expectant moms are lead to believe that VBACs are risky and cesareans are not.

What most moms signing up for cesareans don’t know, is that this decision not only introduces risks that can impact them or their baby immediately, but this decision also impacts their future fertility as well as future cesarean deliveries and babies.  And some of these complications increase with each surgery.  As they say, “Clearly, all the risks of primary cesarean delivery are only increased for repeat cesareans, and increase even more with third, fourth, and higher-order cesarean deliveries.”

This is a great article detailing the risks of cesareans, but I’ll just list the risks below.  If you wish to read more in detail, you can go here: Risks Associated With Cesarean Delivery

Short-term Risks of Cesarean Delivery

  • Maternal Death (yeap, that is the first one they list)
  • Thromboembolism – which is define as “blockage of a blood vessel by a clot that can travel in the bloodstream to the heart, lungs or brain and cause serious damage.”  If the clot goes to your brain, that’s a stroke.  It goes to your heart, that is a heart attack.  If the clot goes to your lungs, that’s a pulmonary embolism.  None of these things are good.
  • Hemorrhage – “The risk of hemorrhage requiring blood transfusion increases substantially with increasing number of prior cesarean deliveries.”
  • Infection – “most common complications of cesarean delivery” affecting 85% of women who labored prior and 4-5% of women with intact membranes.  “Wound infections may occur in 2.5% to 16% of cesareans.”
  • Incidental Surgical Injuries – typically the bladder, bowel or ureters which, if not corrected soon, can cause other complications such as sepsis (major, serious infection), renal (kidney) failure, or fistula formation. 
  • Extended hospitalization– some people view their stay at the hospital as a vacation, me, I like my vacations pain free and with better food, but to each their own!
  • Emergency Hysterectomy – This unfortunately happened to this woman.  “. . . those who did have a hysterectomy were 13 times more likely to have been delivered by cesarean section.”
  • Pain – This little word is so powerful.  Pain is such an easy thing to overlook or to say, yeah, that’s obvious, but when you are trying to care for a newborn, or a newborn and an older child, the risk of pain is huge.  And pain for some women can go on for months.  It took me 18 months for my scar to not be oddly numb, yet sensitive. From the article, emphasis mine:
    • “A study of 242 primiparous women reported that all those who underwent cesarean deliveries (both planned and unplanned) required narcotic pain medications compared with 11% of those who delivered vaginally.Having to relieve pain with narcotic pain medications can have a significant impact on initial bonding between the mother and the newborn and on breastfeeding success rates, as well as maternal functioning postpartum; in addition, the risk for postpartum depression may be greater.”
  • Poor Birth Experience – “more likely to report dissatisfaction with their birth experience compared with those who delivered vaginally . . . less early contact with their newborns . . . significantly longer time before their first contact with their baby . . . more likely to cite a poorer score for their initial contact with their baby.”

Long-term Risks of Cesarean Delivery

  • Readmission to the Hospital – ” . . . postpartum readmission to the hospital was significantly greater for those who delivered by cesarean delivery.”
  • Pain – ” . . . more likely to report pain to be a problem in the first 2 months after delivery.”  A survey of 1500 women who had cesareans in the past 24 months said, “incisional pain was a major problem 25% of the time, and a major or minor problem 83% of the time” and at 6 months postpartum, 7% of CS moms reported incisional pain compared with 2% of vaginal birth moms who reported perineal pain.
  • Adhesion Formation – “. . . is common and significantly contributes to the risk of complications at future deliveries . . . reported increased risk of ectopic pregnancy among women with prior cesarean deliveries.”
  • Infertility/Subfertility – “. . . more likely to be unable to conceive a pregnancy for more than 1 year”

Risks for the Newborn of Cesarean Delivery

  • Neonatal death (they listed this first)
  • Respiratory difficulties – “. . . probably result from a failure of the mechanisms to resorb fetal lung fluid that are typically triggered during vaginal birth . . .3 times more common after elective cesarean delivery than after vaginal delivery”
  • Asthma – “. . . those delivered either by planned or unplanned cesarean were approximately 30% more likely than those delivered vaginally to have been admitted to the hospital for asthma during childhood”
  • Iatrogenic Prematurity – This means that the baby was premature because the cesarean occurred before the baby was ready to be born.  This typically happens with scheduled cesareans.
  • Trauma – Meaning the baby is accidentally cut by the surgeon
  • Failure to breastfeed

Risks of Cesarean Delivery to Future Pregnancies

  • Uterine Rupture – For more stats on this go here.
    • A population-based study of more than 255,000 women in Switzerland found that the incidence of uterine rupture for a woman with no previous cesarean delivery was 0.007%. That incidence rose to 0.192% for a woman with a prior cesarean delivery who planned a repeat cesarean delivery, and rose even higher to 0.397% for women who planned a trial of labor after a prior cesarean delivery. 
  • Abnormal Placentation – This means that your placenta either implants over the opening of the cervix (placenta previa) which means you have to have another cesarean or that your placenta grows through the uterine wall (placenta accreata) which can mean the placenta needs to be manually or surgically removed and puts you at a greater risk of post-partum hemorrhage.
    • . . . women with at least 1 prior cesarean delivery had approximately 3 times the risk of having a placenta previa at the time of delivery compared with women with no prior cesarean deliveries, and this risk increased substantially with increasing numbers of prior cesarean deliveries — reaching nearly 45 times the risk for women with 4 or more prior cesarean deliveries.
  • Hysterectomy – “As the number of prior cesarean deliveries rises, the risk of cesarean hysterectomy increases dramatically.”

As I’ve said before:

VBACs have risks.

Cesareans have risks.

Please understand all the information before making a decision.

Learn more here: Elective Cesarean Surgery Versus Planned Vaginal Birth: What Are the Consequences?