ICAN of Somerset County, NJ

Safety Comparison of VBAC vs Elective Repeat C-Section

The big question on everyone's mind when deciding whether to choose a VBAC or repeat c-section is:

"What are the risks of a VBAC vs the risks of a repeat c-section?"

Too often, women are sold on repeat c-sections by their doctors who stress the risks of VBAC but gloss over the risks of repeat c-sections

So....  let's put some statistical wording to this...

 

The study by Landon, et al Source 1 (listed below with raw numbers and percentages) shows various risks for VBAC and ERCS.  I am choosing the Landon study to cite since it involved a huge number of women and can give strong statistical significance:

 

Risks of choosing a a TOL (trial of labor) vs an ERCS (elective repeat c-section):

•    More likely to suffer a uterine rupture – the rupture rate in the TOL group (see comments below on the make up of the TOL group)*** was 0.7%; there were no ruptures in the ERCS group, however, women who presented in early labor and did not have a documented intention to labor were excluded so it is possible that women went into labor before their scheduled c-section and ruptured but were excluded from this study’s data

• 1.4 times more like to have a uterine dehisence (typically a benign, thin area in the uterus)

• 1.7 times more likely to need a tranfusion

• 1.6 times more likely to develop endometriosis

• 1.3 times more like to have another adverse event such as (broad ligament hematoma, cystotomy, bowel injury, ureteral injury)

• 1.6 times more likely for the baby to die (doesn't sound like that big of a difference right?  Remember that babies only die in about 2-10% of uterine ruptures according to many studies AND babies do die after c-sections.  In fact, a recent study showed that babies were more likely to die after elective c-sections than planned vaginal births that were not necessarily VBACs)  The absolute risk of neontal death is 0.08% with a TOL vs 0.05% in an ERCS; stated otherwise, the risk of neonatal death is 1 in 1250 babies with a TOL vs 1 in 2000 with an ERCS .
  

Risks of choosing an ERCS over a TOL:

• 1.5 times more likely to need a hysterectomy

• 2.5 times more likely to have a thromboembolic disease (deep venous thrombosis or pulmonary embolism)

• 2 times more likely for mother to die (The absolute risk of death was 0.04% with an ERCS cs 0.02% with a TOL; stated otherwise, 1 in 2500 mothers will die due to an ERCS vs 1 in 5000 mothers will die with a TOL)

• 
  

Risks of a successful VBAC delivery (remember that TOL can end in repeat c-sections) vs an ERCS:

• 1.2 times more likel to need a transfustion

Risks of an ERCS vs a succcessful VBAC:

• 3 times more likely for mother to need a hysterectomy

• 5 times more likely to have a thromboembolic disease (deep venous thrombosis or pulmonary embolism)

• 1.5 times more likely to develop endometriosis

• 4 times more likely for mother to die

***Keep in mind that the TOL (trial of labor group included 17,898 women total):

Those 17,898 included women who had more than 1 previous cesarean and a variety of incision types which could put them at greater risk for uterine rupture/adverse events than most women who attempt VBAC with just 1 prior c-section and a low transverse scar:

Breakdown of the number of previous cesareans:

                 •    16,915 (94.5%) had 1 prior cesarean
                 •    871 (4.9%) had 2 cesareans
                 •    84 (0.5) had 3 cesareans
                 •    20 (0.1%) with 4 cesareans

               8 women had an unknown prior # of c-sections

       

            Breakdown of Incision type:

    •   80.9% (14,483) had a low transverse incision (this is known to be the safest incision type to VBAC with)
    •    0.6% (102) had low vertical incision (2 ruptures  or 2.0%)
    •   17.9% (3206) had unknown type of incision (15 ruptures  or 0.5%)
    •    0.6% (105) had Classical, inverted T or J (2 ruptures  or 1.9%)
    •    0.01% (2) had unclassified (0 ruptures)

Other risk factors that may increase the risk of uterine rupture:

• About 25% of the women in the TOL group had their labors induced (with prostoglandins or pitocin) and/or augmented with pitocin which also increases risk of uterine rupture

• About 25% of the women in the TOL group were less than 2 years from their previous c-section.
  

These risks are a good overall indication of the risk of repeat c-section vs the risk of VBAC; however, your individual risk may be lower depending on your individual situation (management or lack of management of your labor to avoid pitocin and induction agents), length of time between deliveries, whether you've had a vaginal birth, number of previous c-sections, etc)

 

SOURCE 1:

MATERNAL AND PERINATAL OUTCOMES ASSOCIATED WITH A TRIAL OF LABOR AFTER PRIOR CESAREAN DELIVERY
(Landon study, 2004 NEJM)

METHODS:

    * Results obtain from 19 academic medical centers
    * 45,988 women with cesarean history and single gestations included:
       * 17,898 (39%) underwent TOL
        * 15,801 (34%) had elective cesareans
    * 9,013 (20%) had indications for repeat cesarean
    * 3,276 (7%) presented in early labor; intentions unknown

TOL group (n=17,898):

    * 16,915 (95%) had 1 prior cesarean
    * 975 (5%) had more than 1 cesarean:
          o 871 (89%) had 2 cesareans
          o 84 (9%) had 3 cesareans
          o 20 (2%) with 4 cesareans

Maternal Complications

    TRIAL OF LABOR GROUP (n=17,898)
        Complications
            Uterine rupture = 124 (0.7%)
            Uterine dehisence = 119 (0.7%)
            Hysterectomy = 41 (0.2%)
            Thromboembolic disease (deep venous thrombosis or pulmonary embolism) = 7 (.04%)
            Transfusion = 304 (1.7%)
            Endometriosis = 517 (2.9%)
            Maternal Death = 3 (0.02)
            Other maternal adverse events (broad ligament hematoma, cystotomy, bowel injury, ureteral                     injury) = 64 (0.4)
            One or more of the above events = 978 (5.5%)

   

ELECTIVE REPEAT CESAREAN DELIVERY GROUP (n=15,801)
        Complications   
            Uterine rupture = 0
            Uterine dehisence = 76 (0.5%)
            Hysterectomy = 47 (0.3%)
            Thromboembolic disease (deep venous thrombosis or pulmonary embolism) = 10 (0.1%)
            Transfusion = 158 (1.0%)
            Endometriosis = 285 (1.8%)
            Maternal Death = 7 (0.04%)
            Other maternal adverse events (broad ligament hematoma, cystotomy, bowel injury, ureteral                     injury) = 52 (0.3%)
            One or more of the above events = 563 (3.6%)

Maternal Outcomes According to Outcome of Trial of Labor (n=17,898)

    Failed Vaginal delivery (n=4,759)
        Complications
            Uterine rupture = 110 (2.3%)
            Uterine dehisence = 100 (2.1%)
            Hysterectomy = 22 (0.5%)
            Thromboembolic disease (deep venous thrombosis or pulmonary embolism) = 4 (0.1%)
            Transfusion = 152 (3.2%)
            Endometriosis = 365 (7.7%)
            Maternal Death = 2 (0.04%)
            Other maternal adverse events (broad ligament hematoma, cystotomy, bowel injury, ureteral                     injury) = 63 (1.3%)
            One or more of the above events = 669 (14.1%)

   

   Successful Vaginal Delivery (n=13,139)
        Complications
            Uterine rupture = 14 (0.1%)
            Uterine dehisence = 19 (0.1%)
            Hysterectomy = 19 (0.1%)
            Thromboembolic disease (deep venous thrombosis or pulmonary embolism) = 3 (0.02%)
            Transfusion = 152 (1.2%)
            Endometriosis = 152 (1.2%)
            Maternal Death = 1 (0.01)
            Other maternal adverse events (broad ligament hematoma, cystotomy, bowel injury, ureteral                     injury) = 1 (0.01)
            One or more of the above events = 309 (2.4%)

Perinatal Outcomes for Term Infants

    TRIAL OF LABOR GROUP (n=17,898)
        Antepartum stillbirth
            37-38 week = 18 (0.40%)
            > or = 39 weeks = 16 (0.20%)
        Intrapartum stillbirth
            37-38 week = 1 (0.02%)
            > or = 39 weeks = 1 (0.01%)
        Hypoxic-ischemic encephalopathy = 12 (0.08%)
        Neonatal death = 13 (0.08%)
        One or more of the above = 59 (0.38%)

    ELECTIVE REPEAT CESAREAN DELIVERY GROUP (n=15,801)
        Antepartum stillbirth
            37-38 week = 8 (0.10%)
            > or = 39 weeks = 5 (0.10%)
        Intrapartum stillbirth
            37-38 week = 0
            > or = 39 weeks = 0
        Hypoxic-ischemic encephalopathy = 0
        Neonatal death = 7 (0.05%)
        One or more of the above = 20 (0.13%)

STUDY REFERENCE:
NEJM
Volume 351:2581-2589  December 16, 2004  Number 25

Maternal and Perinatal Outcomes Associated with a Trial of Labor after Prior Cesarean Delivery

Mark B. Landon, M.D., John C. Hauth, M.D., Kenneth J. Leveno, M.D., Catherine Y. Spong, M.D.,
Sharon Leindecker, M.S., Michael W. Varner, M.D., Atef H. Moawad, M.D., Steve N. Caritis, M.D.,
Margaret Harper, M.D., Ronald J. Wapner, M.D., Yoram Sorokin, M.D., Menachem Miodovnik, M.D.,
Marshall Carpenter, M.D., Alan M. Peaceman, M.D., Mary Jo O'Sullivan, M.D., Baha Sibai, M.D.,
Oded Langer, M.D., John M. Thorp, M.D., Susan M. Ramin, M.D., Brian M. Mercer, M.D.,
Steven G. Gabbe, M.D., for the National Institute of Child Health and Human Development
Maternal–Fetal Medicine Units Network

Below are some other good sources for comparing the risks of VBAC with the risks of ERCS:

 

SOURCE 2:

Here is a chart from a Candian source comparing the risks of a planned vaginal birth vs a planned c-section:

 

SOURCE 3:

Blog post on the risks of c-section vs risk of VBAC:

Source 4:

The consequences of a planned vaginal birth vs planned c-section from the Lamaze Institute:

 

 

What happens if I have a uterine rupture?

Following are summaries of studied that looked at the uterine rupture cases and what happened to mother and baby.

Study 1
UTERINE RUPTURE AFTER PREVIOUS CESAREAN DELIVERY: MATERNAL AND FETAL CONSEQUENCES

Anna S. Leung, MD, Eleanor K Leung, MD, and Richard H. Paul, MD
American Journal of Obstetrics and Gynecology
October 1993: 945-950

Study population: largely indigent Hispanic women
Study location: Los Angeles County - Southern CA Women's Hospital

uterine rupture (UR) = symptomatic uterine scar separation
asymptomic uterine dehiscences were excluded

Total births from 1/1983-6/1992: 159,456
    - 16,467 (10.1%) with pevious c-section
        - 11,179 (61%) had a trial of labor
            - 9763 (82%) had VBACs

106 total cases or UR; however complete records were only available for 99 cases so that is what is presented here.

3 groups:
    Total fetal extrusion into abdominal cavity
    Partial fetal extrusion into abdominal cavity
    No fetal extrusion into abdominal cavity

Total fetal extrusion into abdominal cavity (n=28)
    # of previous c-sections
        1 = 13 (46%)
        2 = 12 (43%)
        3 = 3 (11%)
        4 = 0

    previous scar
        classical/vertical = 6 (21%)
        transverse = 16 (58%)
        unknown = 6 (21%)

    arrived @ hospital with fetal distress = 5 (17.9%)
    c-section delivery = 28 (100%)
    labor induced with oxytocin = 5
    labor augmented with oxytocin = 16
    epidural = 12 (43%)
    pain = 6 (21%)
    vaginal bleeding = 10 (36%)

    Maternal death = 0
    Blood transfusion = 8 (29%)
    Hysterectomy = 4 (14%)
    Perinatal death = 4 (14%)
    Perinatal asphyxia = 1 (4%)
    Respiratory distress = 5 (25%)

Partial fetal extrusion into abdominal cavity (n=13)
    # of previous c-sections
        1 = 8 (62%)
        2 = 5 (38%)
        3 = 0
        4 = 0

    previous scar
        classical/vertical = 2 (15%)
        transverse = 8 (62%)
        unknown = 3 (23%)

    arrived @ hospital with fetal distress = 0
    c-section delivery = 13 (100%)
    labor induced with oxytocin = 4
    labor augmented with oxytocin = 6
    epidural = 10 (77%)
    pain = 1 (8%)
    vaginal bleeding = 0

    Maternal death = 0
    Blood transfusion = 4 (31%)
    Hysterectomy = 4 (31%)
    Perinatal death = 0
    Perinatal asphyxia = 2 (15%)
    Respiratory distress = 0

No fetal extrusion into abdominal cavity (n=58)
    # of previous c-sections
        1 = 40 (69%)
        2 = 15 (26%)
        3 = 2 (3%)
        4 = 1 (2%)

    previous scar
        classical/vertical = 3 (5%)
        transverse = 40 (69%)
        unknown = 15 (26%)

    arrived @ hospital with fetal distress = 8 (14%)
    c-section delivery = 43 (75%)
    labor induced with oxytocin = 9
    labor augmented with oxytocin = 32
    epidural = 25 (44%)
    pain = 6 (11%)
    vaginal bleeding = 1 (2%)

    Maternal death = 1 (2%)
    Blood transfusion = 17 (30%)
    Hysterectomy = 11 (19%)
    Perinatal death = 2 (2%)
    Perinatal asphyxia = 2 (5%)
    Respiratory distress = 1 (2%)

Of the 13 women who arrived at the hospital with acute fetal distress (obviously no epidural at this point):
    - 5 had classic/vertical  scars
    - 8 had unknown scars
    - 6 felt pain
    - 3 had vaginal bleeding
    - 10 were having contractions
    - 4 of the babies died (3 of the 4 women complained of pain whose babies died)
    - the rest had few (if any complications) and 6 babies had 5 minute apgars of 8 or greater

NOTE:
- 4 of the 6 neonatal deaths (3 fetuses from the total extrusion group and 1 from the no extrusion group) occurred in patients who underwent immediate c-sections for "acute fetal distress" upon admission.

-Only 2 neonatal deaths occured in women undergoing a TOL

- No patient in whom the only FHR (fetal heart rate) abnormality was a prolonged deceleration ohad a neanate with significant perinatal  morbidity when the delivery occurred within 17 minutes on the onset of prolonged deceleration.

- This study, BY ADMISSION, presents the most severe spectrum of UR b/c most patients (90%) undergoing a TOL had unknown scars (previous scar types were usually noted during the c-section)

- Overall incidence of UR was 0.87% which is consistent with other studies.

- UR occurred before an observed TOL in 13 out of the 99 cases.  Of those 13, 9 had previous classical/vertical scars or had 3 or more c-sections.  In reality, those 9 women probably would have had elective repeat c-sections if that information was known and they didn't go into labor too early.  So only 3 cases of UR could not have been prevent with elective c-sections close to term. 

- Performing elective c-sections in patients with prior unkonw uterine scars to prevent UR is NOT supported.

- When UR happened, the chance of the baby's death was 6%

STUDY 2
MATERNAL AND PERINATAL OUTCOMES ASSOCIATED WITH A TRIAL OF LABOR AFTER PRIOR CESAREAN DELIVERY

114 uterine ruptures in 17,898 VBAC attempts


METHODS:

    * Results obtain from 19 academic medical centers
    * 45,988 women with cesarean history and single gestations included:
       * 17,898 (39%) underwent TOL
        * 15,801 (34%) had elective cesareans
    * 9,013 (20%) had indications for repeat cesarean
    * 3,276 (7%) presented in early labor; intentions unknown

TOL group:

    * 16,915 (95%) had 1 prior cesarean
    * 975 (5%) had more than 1 cesarean:
          o 871 (89%) had 2 cesareans
          o 84 (9%) had 3 cesareans
          o 20 (2%) with 4 cesareans


Perinatal outcomes after uterine rupture in term pregnancies (n=114)
    Intrapartum stillbirth = 0
    Hypoxic-ischemic encephalopathy - 7 (6.2%)
    Admission to neonatal intensive care unit = 46 (40.4)
    5 minute apgar score < or = 5 = 16 (14.0)
    Imbilical-artery blood pH < or = 7.0 = 23 (33.3)
    Neonatal deaths = 2 (1.8%)

STUDY REFERENCE:
NEJM
Volume 351:2581-2589  December 16, 2004  Number 25

Maternal and Perinatal Outcomes Associated with a Trial of Labor after Prior Cesarean Delivery

Mark B. Landon, M.D., John C. Hauth, M.D., Kenneth J. Leveno, M.D., Catherine Y. Spong, M.D.,
Sharon Leindecker, M.S., Michael W. Varner, M.D., Atef H. Moawad, M.D., Steve N. Caritis, M.D.,
Margaret Harper, M.D., Ronald J. Wapner, M.D., Yoram Sorokin, M.D., Menachem Miodovnik, M.D.,
Marshall Carpenter, M.D., Alan M. Peaceman, M.D., Mary Jo O'Sullivan, M.D., Baha Sibai, M.D.,
Oded Langer, M.D., John M. Thorp, M.D., Susan M. Ramin, M.D., Brian M. Mercer, M.D.,
Steven G. Gabbe, M.D., for the National Institute of Child Health and Human Development
Maternal–Fetal Medicine Units Network

Study 3

UTERINE RUPTURE DURING TRIAL OF LABOR AFTER PREVIOUS CESAREAN SECTION

by Richard M. Farmer, MD, PhD, Thomas Kirschbaum, MD, Daniel Potter, Thomas H. Strong, MD and Arnold L. Medearis, MD


Am J Obstet Gynecol, October 1991 (996 - 1001)


Location: Los Angeles COunty - University of California WOmne's Hospital
Study period: Jan 1983 - Dec 1989

Records of 137 patients with scar separation were reviews
Patients who underwent a trial of labor after cesarean either had a low-transverse, low vertical or unknown uterine incision
        exclusion criteria from 1983 -1985 were: unknown uterine scar, previous classical                         incision, or transverse lie that failed version
        Patients with multiple gestation or breech presentation were NOT excluded

-Fetal heart rate was monitored witha fetal scal electrode or ecxternal Doppler technique
-Uterine activity as monitored with an intrauterine pressure catheeter when cervical dilation alllowed or with an external tocodynamometer
-Oxytocin (pitocin) and epidural anesthesia were administered for oebstretric indications
-A uterine exploration was performed after each successful vaginal delivery to establish scar status

Total deliveries = 119,395
    total deliveries with history of cesarean = 11,041 (9.3%)
        Patients who underwent a trial of labor = 7598 (69%)
            patients who delivered vaginally = 6021 (79%)

OUTCOMES BASED ON DELIVERY
    All patients with a history of cesarean (n=11,041)
        uterine rupture rate = 70 (0.6% )
        uterine dehisence = 67 (0.6%)

    Patients who underwent a trial of labor (n = 7,598)
         uterine rupture rate = 61 (0.8% )
         uterine dehisence = 54 (0.7%)

                 Patients who had a successful trial of labor (n=6,021)
                        uterine rupture rate = 7 (0.1% )
                        uterine dehisence = 28 (0.5%)

                Patients who had a failed trial of labor (n=1,577)
                        uterine rupture rate = 54 (3.4% )
                        uterine dehisence = 26 (1.7%)

    Patients who had an elective repeat c-section (n=3,443)
        uterine rupture rate = 9 (0.3% )
        uterine dehisence = 13 (0.4%)

INDICATIONS OF UTERINE SCAR SEPARATION (n=137)
    Uterine rupture during failed trial of labor (n=54)
        Fetal distress =  46 (85.2%)
        arrest disorders = 7 (13.0%)
    Uterine dehisence during failed trial of labor (n=26)
        fetal distress = 7 (26.9%)
        arrest disorders = 19 (69.2%)
       

MATERNAL AND PERINATAL OUTCOMES ASSOCIATED WITH UTERINE RUPTURE IN PATIENTS WHO UNDERWENT A TRIAL OF LABOR(n=61)
        maternal death = 1 (1.6%)
        transfusion = 13 (21.3%)
        urologic injury = 15 (24.6%)
        hysterectomy = 14  (23.0%)
        perinatal death = 1  (1.6%)
        NICU admission = 10 (16.4%)


NOTES:

Trial of labor group included women who had more than 1 previous c-section.  Avg # c-sections = 1.4 (4 women had more than 2 previous c-sections)

Oxytocin used during trial of labor in 73.8% of patients with a uterine rupture and in 74.1% of patients with a uterine dehisence

Only 1 baby died in this study following a uterine rupture with a trial of labor which was 1.6% chance of a perinatal death.

Epidurals were used in 27.9% of patients with UR and 35.2% of patients with UD

Avg labor for patients with UR was 14.8 +/- 10.6 hours
Avg labor for patients with UD was 15.0 +/- 8.2 hours

Women with either a rupture or dehisence were advised not get pregnant again.  13 did subsequently deliver children. 2 of had inadvertant trial of labor with succesful vaginal delivery
        Dehisence group (n=7)
            cesarean delivery = 6 (5/6 had intact scars)
            vaginal deivery: 1 (dehisence was detected through manual exploration of uterus)
        Rupture group (n=6)
            cesarean delivery = 5 (4/5 had intact scars)
            vaginal deivery: 1 (no rupture or dehisence was detected through manual exploration                 of uterus)

Abdominal pain and bleeding on occurred 3.4% and 7.6%, respectively, in labors with scar separation

Use of oxytocin in patients who underwent a trial of labor but did not have a scar separation is not uknown

MORE SOURCES ON UTERINE RUPTURE:

Overview of Uterine Rupture looking at numerous studies and pulling information out

Uterine Rupture Studies

Facts about uterine rupture

Is it risky to VBAC with less than 2 years between births?

Is the risk of UR greater with less than 2 years between births?

STUDY 1

In the July 2006 study by Landon:

UR are not separated out by length of time between deliveries.

However, there were 9 UR in 975 vbaMc attempts.  244 of those women (27.4%) were less than 2 years from their last c-s.  *IF* those 9 UR happened ONLY in women with less than 2 years between births, that would be a UR rate of 3.7%.

There were 115 UR in 16,915 vba1c attempts.  4,043  of those women (25.1%) were less than 2 years from their last c-s.  *IF* those 115 UR happened ONLY in women with less than 2 years between births, that would be a UR rate of 2.8%

Considering 25% of the women in this study were induced and/or augmented, it is NOT likely that the UR only happened in women less than 2 years from their last birth. 

STUDY 2

Single- versus double-layer uterine incision closure and uterine rupture.
Authors: Gyamfi C, Juhasz G, Gyamfi P, Blumenfeld Y, Stone JL. The Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Columbia University, New York, NY, USA. drcynthiagyamfi@yahoo.com
Journal of Maternal-Fetal and Neonatal medicine, Oct 2006; 19(10): 639-643

This study did not find that time interval played a role in uterine rupture.  They did, however, show a much great risk of uterine rupture in single vs double layer suturing of the uterus.  The biggest problem with this study was the routine use of misoprostal (cytoctec) for the induction of labor.

STUDY 3:

Interdelivery Interval and uterine rupture

Emmanuel Bujold, MDa, Camille Bujold, OTa, Emily F. Hamilton, MDb, François Harel, MSca, Robert J. Gauthier, MDa
November 2002, American Journal of Obstetrics and Gynecology

Volumen 187, No 5

1527 women in study
11/1988 through 11/2000
no previous vaginal delivery
low transverse incision
21 UR (1.4%)

Less than 12 months between deliveries (n=21)  1.4%
    Induction of labor 29% (n=5)
    Use of oxytocin 52% (n=11)
    Epidural  (71%) n=15
    VBAC success 62% (n=13)
    UR = 4.8%  (n= 1)

13-24 months between deliveries (n=372)  24.4%
    Induction of labor 23% (n=87)
    Use of oxytocin 63% (n=233)
    Epidural  (76%) n=281
    VBAC success 74% (n=275)
    UR = 2.7%  (n= 10)

25-36 months between deliveries (n=436)  28.6%
    Induction of labor 30% (n=129)
    Use of oxytocin 61% (n=265)
    Epidural  (74%) n=324
    VBAC success 71% (n=310)
    UR = 0.9%  (n=4)

Great than 36 months between deliveries (n=698)  45.7%
    Induction of labor 28% (n=197)
    Use of oxytocin 61% (n=425)
    Epidural  (71%) n=496
    VBAC success 70% (n=488)
    UR = 0.9% (n=6)

NOTES:
Says an interval between pg of less than 24 months is associated with a 2 – 3 fold increase in the risk of uterine rupture.  However, this is a statistical odds ratio.
Study also looked at single vs double layer suturing and found the risk of uterine rupture with  less than 2 years between birth was decreased when you had a double layer suture.

The data for this article is also analyzed here looking at the effect of single vs double layer suturing.  He found a rupture rate of 3.1% for single layer uterine sutures.  However, one must keep in mind the suturing technique and suturing material: this study used almost exclusively chromic catgut suturing material which is not as strong as vicryl which is more commonly used today!  Therefore, take this info with a grain a salt!.  There were a number of letters to the editor that critiqued the single vs double layer sutures study and only one other study came close to corroborating theoe results (and the single layer suture group was incredible small AND they routinely used misoprostal (cytotec) to induce

STUDY 4:

Interdelivery Interval and Risk of Symptomatic Uterine Rupture
THOMAS D. SHIPP, MD, CAROLYN M. ZELOP, MD, JOHN T. REPKE, MD,
AMY COHEN, AND ELLICE LIEBERMAN, MD, DrPH
Copyright © 2001 by The American College of Obstetricians and
Gynecologists. Published by Elsevier Science Inc.
VOL. 97, NO. 2, FEBRUARY 2001

Retrospective study from July 1984 to June 1996

2409 women attempted vbac after 1 c-s with low   transverse incision
There were 29 UR (1.2%)

For intervals of up to 18 months, the UR rate was 2.25% (7 of 311)
    17.0% of these women were induced
    38.6% had oxytocin to augment their labor

For intervals of 19 months or longer, the UR rate was 1.05% (2 of 2098)
    18.5% of these women were induced
    39.0% had oxytocin to augment their labor

Of the women who ruptured:
44.8% were induced
34.5% of the were augmented

NOTES:

Very small sample size of 18 months or less between deliveries
Type of suturing?  Probably chromic (due to dates of the study)
Single or double layer suturing?
Data from one hospital?
What type of induction agent was used??

STUDY 5:

Wilson H. Huang, MD, Dana K. Nakashima, MD, Pamela J. Rumney, RNC,

Kirk A. Keegan, Jr, MD, and Kenneth Chan, MD

OBSTETRICS & GYNECOLOGY
VOL. 99, NO. 1, JANUARY 2002

Retrospective study from 1/1/1997 through 12/31/2000

24,162 deliveries
1516 attempted vbac
1185 had complete record available to be included in this study

Less than 19 months group (n=81)
    8.6% induction rate
    58.0% oxytocin use
    79.0% vbac success (64 of 81)
    0% uterine rupture

More than 19 months group (n=1104)
    19.6% induction rate
    62.0% oxytocin use
    85.5% vbac success (943 of 1104)
    0.3% uterine rupture (3 of 1104)

NOTES:

Very small sample size of 18 months or less between deliveries
Type of suturing? 
Single or double layer suturing?
Data from one hospital
What type of induction agent was used??

Single vs Double layer suturing - the bottom line

So I posted summaries of several studies looking at single and double layer suturing techniques on a low transverse c-section incision.  What does it mean?

The 2 articles that showed an increase in rupture rates used chromic catgut suturing material with a locking or continuous technique.

The articles that showed no difference in uterine rupture rates whether there was  single or double layer varied in technique.  However, overall, it appears that the best way to suture a uterus is using 0-Vicryl (polyglactin) with a non-running/noncontinuous/interrupted technique.  Single or double layering probably doesn't matter.

Single vs Double Layer Suturing in a Cesarean and it's Effect on VBACS - the positive research articles

Okay, now that we know why some obs and midwives want to deny women the right to vbac based on suturing, let's look at some articles that don't report a difference in the rate of UR in single vs double layer (oh, by the way - there are a LOT more of them!)

Unfortunately I do not have full studies for all of them (I noted whether I had the full study or just the abstract at the beginning of each summary).  As I find more studies, I will add them in.

Remember that it appears that suturing type and technique as well as surgeon skill have a lot to do with UR risks!  The research suggests that non-locking polyglactin (0-Vicrul) sutures are the best.

STUDY 1 - I reviewed the FULL STUDY
Uterine rupture, perioperative and perinatal morbidity after single-layer and double-layer closure at cesarean delivery
American Journal of Obstetrics and Gynecology Volume 189, Issue 4, Pages 925-929 (October 2003)

authors: Celeste Durnwald, MD, Brian Mercer, MD
Cleveland, Ohio

Objective
This study was undertaken to evaluate the risks and benefits of single-layer uterine closure at cesarean delivery on the index and subsequent pregnancy.

Study design
A retrospective study of women delivered of their first live-born infants by primary low transverse cesarean delivery (1989-2001) and their subsequent pregnancy at our institution was performed.

Criteria for inclusion
    - women whose first baby was born by c-section and had a low transverse incision

Criteria for exclusion
    - upper uterine segment extension or T-incision
    - prior uterine mymetrial sugery
    - women who delivered either pregnancy before 24 weeks gestation

Study size: N = 768
    Single layer = 267    
    Double layer = 501
      

DEFINITIONS
    Uterine rupture: a full-thickness defect through myometrium and peritoneum
    Single layer suture: 1 continuous running suture applied to the lower uterine segment with additional                 interrupted hemostratic sutures placed as needed
    Double layer suture: second continuous imbricating layer applied over the first layer
    Uterine Window: asymptomatic uterine defect with intact overlying peritoneum

Uterine closure: 99.2% were done with polyglactin 910 suture (0-Vicryl)

Blood loss
    Single layer = 646 mL
    Double layer = 690mL
    p<.01

Trial of labor
    single layer:  182/267 (68.2%)
    double layer:  340/501 (67.9%)

VBAC success (out of the Trial of Labor group)
    single layer:  124/182 (68.1%)
    double layer:  220/340 (64.7%)

Operative time
    Single layer = 46 min
    Double layer = 52 min
    P<.001

Endometriosis
    Single layer = 13.5%
    Double layer = 25.5%
    P<.001

Postoperative stay
    Single layer = 3.5 days
    Double layer = 4.1 days
    P<.001

Induction*
    single layer: 38/182 (20.9%)
    double layer: 55/340 (16.2%)

* None of the 4 UR in the study were associated with prostaglandin use

Oxytocin (pitocin) use:
    single layer: 111/182 (61.0%)
    double layer: 186/340 (54.7%)

Uterine rupture    
    Single layer = 0 total (0%)
    Double layer = 4 total (0.8% of all women in the study with a double layer;  1.2% of those who went         through a Trial of Labor)
    P=.30

Uterine windows (at subsequent cesarean delivery)
    Single layer = 3.5%
    Double layer 0.7%
    P=.046

Conclusion
Single-layer uterine closure is associated with decreased infectious morbidity in the index surgery, but not uterine rupture or other adverse outcomes in the subsequent gestation.

From the Department of Obstetrics and Gynecology, MetroHealth Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA

NOTES
    - There were NO UR in the single layer group in this study! 4 UR in the double layer group
    - Neither group had placenta accreta nor maternal death
    - No cesarean hysterectomies were required
    - Study was done at the same hospital instead of gathering data from more than 1 hospital
    - Significant reduction in endometriosis and postioperative stay
    - Findings were consistent with the Chapman et al study (1997) and the Tucker et al study (1993)
    - None of the 4 UR in the study were associated with prostaglandin use
    - Major difference between this study and the  Bujold et al study (2002) was the type and         technique for uterine suture (The Bujold study detected a 4 fold increase in the rate of UR in         single layer sutures).  This study used polyglactin 910 (0-Vicryl) in a continuous unlocked             closure.  Bujold et al  used a chromic catgut suture in a continuous locked stitch.
                - chromic catgut is degraded by proteolytic enzymes and loses half of its tensile strength                     within 7-10 days; Polyglactin (0-Vicryl) is degraded by hydolysis and maintains all of its tensile                 strength for at least 7 -10 days.

- It is plausible that a running locked closure leads to vascular occlusion and poorer wound healing
    - Mean interdelivery interval with the UR was 2.6 years (only 1 UR case had less than 2 years between     deliveries)
    - No uterine windows/dehiscences were detected in women who had successful vbacs but only 31%         had their uteruses palpated and they may not have been detected anyway
    - To adequately evaluate a 2 fold increased risk of UR after single-layer closure from a 1.2% wiht             double layer closure with 80% power, they would have needed 3848 women

STUDY 2 - I reviewed the full study

Impact of single layer or double layer closure on uterine rupture in subsequent labour
Shahid Irshad Rao, Bushra Faiz, Saqib Ramzan,
Nishtar  Hospital and Medical College, Multan
http://www.pmrc.org.pk/uterine.htm

Pakistan J. Med. Res

Vol 42 No.1, 2003

Objectives: The purpose of this study was to assess the impact of single layer or double layer closure on uterine rupture at subsequent delivery.

METHODS: 
    Total number of women in the study undergoing trial of labor (TOL): N= 1041

Criteria for inclusion
-    one previous transverse lower segment caesarean section and going for trial of labour
-    had operative details of previous caesarean delivery.
-    spontaneous onset of labour and none had induced labour.

Type of closure    
        Single closure     457/1041  (43.9)
        Double closure     584/1041   (56.1)

VBAC:  802/1041 (77.04%)
Repeat c-section after TOL:  225 (21.6%)

Outcome of Labor
    Single layer closure (n=457)
        - Vbac:  336/457 (73.5%)
            - uterine rupture: 6/457 (1.3%)  NOTE: chromic catgut suture was used  in 4 cases ;  polyglycolic acid (Vicryl-type) suture was used in 2 cases
        - c-section: 115/457 (25.2%)
            - uterine dehiscence: 9/115 (7.8%)
       

    Double layer closure (n=584)
        - Vbac:  466/584 (79.8%)
            uterine rupture: 8/584 (1.4%)
        - c-section: 110/584 (18.8%)
            uterine dehiscence: 10/110 (9.1%)

Uterine Rupture: 14/1041 (1.34%) 
     single layer: 6/647 (1.3%)
     double layer: 8/584 (1.4%)

Conclusion: Single layer uterine closure with polyglycolic acid suture gives as strength to uterine scar as double uterine closure. In addition there is short operative time and less postoperative morbidity observed in single layer closure.

NOTES
-    no induction/augmentation
-    UR rates are still higher than recent averages.
- chromic catgut used in most UR cases (which is the suturing they used in the negative articles!!)
-suturing in double layer UR cases not stated.

STUDY 3 - I reviewed the FULL STUDY

One- versus two- layer closure of a low transverse cesarean: the next pregnancy
Authors: SJ Chapman, J Owen, and JC Hauth

Obstetrics & Gynecology 1997;89:16-18
© 1997 by The American College of Obstetricians and Gynecologists


Study size: N=164
    Single layer suture = 83
    Double layer suture = 81

ERCS group = 19/164 (12%)
TOL group = 145/164  (88%)

UTERINE CLOSURE in TOL group
    single layer: 70/145 (48.3%)
    double layer: 75/145 (51.8%)

OXYTOCIN (PITOCIN) USE
    85/145 women undergoing TOL (study does not specify percentages in each group)

UTERINE DEHISCENCE
    single layer:  1/70 (1.4%)
    double layer: 0/75 (0%)

VBAC success
    single layer group: 56/70 (80%)
    double layer group: 64/75 (85.3%)

Uterine Rupture: 0% overall
      single layer: 0/70
      double layer: 0/75

Perinatal death
      single layer: 2 (one stillbirth and 1 from extreme prematurity)
        double layer: 3 (2 still births and 1 from extreme prematurity

Length of labor, mode of delivery, duration of hospital stay, gestation at delivery, and the incidences of uterine scar dehiscence, chorioamnionitis, postpartum metritis, hemorrhage, transfusion, and abnormal placentation did not differ significantly between the groups. Selected neonatal outcomes, including Apgar scores, cord pH, birth weight, and perinatal death, were similar between groups as well.

CONCLUSIONS: These findings suggest that the type of low transverse cesarean closure does not significantly affect the outcome of the next pregnancy.

NOTES:

• 1-0 chromic catgut used to suture all women
• There were NO uterine ruptures in either group
• study included twin gestations in TOL group (3 in single layer group and 3 in double layer group)
• small sample size limits statistical power

STUDY 4 - I reviewed the abstract only

[Does the suture material and technique have an effect on healing of the uterotomy in cesarean section?]
[Article in Croatian]

Sestanović Z, Mimica M, Vulić M, Roje D, Tomić S.
Klinika za zenske bolesti i porode KB Split.

OBJECTIVE: To present the influence of different suturing techniques and different materials (catgut plain, Dexon and Vicryl) on healing of lower transverse uterotomy (in further text uterotomy) in Cesarean section (CS).

Uterotomies were sutured by four ways:
    Single layer sutures:
        Group A: one row interrupted (non-locking)
        Group B: one row continuous (locking)
    Double layer sutures
        Group C: two rows interrupted
        Group D: two rows interrupted and continuous

7830 women reviewed in study; 1946 (24.8%) had repeat deliveries and were included in the results (n=1946)

ERCS = 887 (45.0%)
Vbacs = 1059 (55.0%)

There were 15 (0.8%) uterine-rupture dehisences (URD) out of 1946 deliveries
    Catgut group (n=302)
        11 (3.6%) URD
            9 (7.2%) in Group D (n=125)
            2 (1.7%) in Group C (n= 20)
            0 in Group A (n=57)

    Dexon Group (n= 226)
        No URD diagnosed

    Vicryl Group (n=1486)
        4 (0.28%) URD{
           - 1 (0.16%) in Group A (n=615)
            - 1 (0.3%) in Group B (n=333)
            - 1 (0.52%) in Group C (n=190)
            - 1 (0.35%) in Group D (n280)       
   
Uterine Rupture overall:
      single layer: 2/948 (0.2%) --> both were Vicryl sutures
      double layer: 13/615 (2.1%)  --> 11 of these used catgut sutures   

CONCLUSIONS: The best uterine scar is the one after using one layer interrupted Vicryl and Dexon suture. The worst healing results were obtained after two-row interrupted and continuous sutures using catgut.

NOTES
    - induction/augmentation unknown

PMID: 15038214 [PubMed - indexed for MEDLINE]

STUDY 5 - I reviewed the full study

Trial of Labor after a one- or two- layer closure of a low transverse uterine incision

authors:  J. Martin Tucker, MD, John C. Hauth, MD, Pam Hodgkins, RN, John Owen, MD, and Carey L. WInkler, MD
Birmingham, AL

Am J of Obstet Gynecol, Feb 1993: 545-546

OBJECTIVE:  A retrospective review to evaluate the safey of a trial of labor after a one-layer closure of a low transverse uterine incicion

Inclusion
    - only women who underwent a low transverse cesarean section without vertical extension

UTERINE CLOSURE
    single layer: 149 women
        defined as one continous layer of locking No. 1 chomic catgut suture
    double layer: 143 women
        defined as 2 continous layers with the first one locked

Uterine Rupture
    single layer: 0/149
    double layer: 0/143

Uterine scar separation (asymptomatic)*
    single layer: 3/149 (2.1%)
    double layer: 5/143 (3.5%)

* this may have been higher due to lack of documentation in operative and delivery summaries

CONCLUSION:  These data support the premise that a trial of labor should not be altered by whether the patient had a prior one- or two- layer closure of the low transverse cesarean scar.

NOTES
    - Very small sample size (n= 292 women)
    - No uterine ruptures in either single or double layer group
    - No information given on other UR risk such as induction, augmentation, time interval between deliveries and maternal age.
    - This appears to be the first study to look at the effect of single vs double layer suturing.
    - Study only included women in 1 hospital.

Single vs Double Layer Suturing in a Cesarean and it's Effect on VBACS - the negative research articles

There has been a lot of talk lately about suturing on a cesarean.  Many providers are refusing to allow vbacs with a single layer suture (as opposed to a double layer suture).  Is there really a higher risk with a single layer??  Or is it yet another way for obs to deny women the right to birth the way they choose?

I've been looking into studies which address this issue.  I'm working on getting the full studies.  In some cases, I just have abstracts to report on. There are 2 studies that show a huge increase in the rate of uterine rupture in single layer sutures.

Let's look at the first one:

STUDY 1 - I reviewed the complete study

Single- versus double-layer uterine incision closure and uterine rupture.

Authors: Gyamfi C, Juhasz G, Gyamfi P, Blumenfeld Y, Stone JL. The Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Columbia University, New York, NY, USA. drcynthiagyamfi@yahoo.com

Journal of Maternal-Fetal and Neonatal medicine, Oct 2006; 19(10): 639-643

OBJECTIVE: To evaluate whether closure of the uterine incision with one or two layers changes uterine rupture or vaginal birth after cesarean section (VBAC) success rates. (Transverse uterine incision)

METHODS: Reviewed VBAC attempts from 1/1/1996 to 12/31/2000 at the Mount Sinai School of Medicine in NYC.

Criteria for inclusion:
    Single, previous low transverse cesarean section

Criteria for exclusion:
    - multiple gestation
    - more than 1 c-section
    - previous scar other than low transverse
     - gestational age at delivery < 36 weeks
     - previous operative report unavailable

Definitions
    Uterine Rupture (UR): complete separation of the previous uterine scar with extrustion of fetal parts     into the peritoneal cavity

    Single layer closure: one continuous, locked layer of the lower segment incision

    Double layer closure: initial layer was closed in a running locked fashion; second layer was a     continuous, imbricating layer

Study size:  N = 948 women
    Single layer = 35
    Double layer = 913

Uterine Rupture (rate) =  1.6% overall
   Single layer = 3/35 (8.6%)
    Double layer = 12/948 (1.3%)
    p=0.015

Vbac success
    Single layer = 74.3%
    Double layer – 77% p= 0.685

Time interval between delivery (Months)
    Single layer = 26.4 +- 14.7 months
    Double layer = 38.6 +- 22.2 months

Induction*
    Single layer = 26.4%
    Double layer = 38.6%

* Inductions were usually done with prostaglandins.  Up until 1999, misoprostol (aka Cytotec) was regularly used for inductions in previous scarred uteri

NOTES
-    During study period, overwhelming majority of obs closed the incisions with No1. chromic.  All the UR cases involved No. 1 chromic in either a single or double layer.
- The number of women included in the single layer suture group (35) is WAY too small to be statistically significant
-    Double layer group had a longer time interval between pregnancies
-    Bujold and coworkers obtained similar results in a 2002 study published in Am J Obstet Gynecol.  However they used similar techniques:  both used chromic catgut to close the uterine incision which other studies have shown is not as good of a suturing material
-    Durnwald and Mercer found no increase in UR when 1 or 2 layers were used and their study used 0-Vicryl suture material (polyglactin 910) which is known to keep it’s tensile strength longer.
-    One quarter to one half of the women were induced.  Cytotec was used as an induction aid for 3 out of 4 years of this study.  Cytotec  should not be used as an induction aid for any women (due to increased chance of uterine hyperstimulation), especially not women with a scarred uterus!  The study does not specifically state whether cytotec (or another cervical ripening agent or pitocin) was used in the cases of UR
-    Rates in this study were much higher than commonly quoted UR rates (0.4 -0.7%).  That ALONE should raise a red flag with this study!
-    Landon, et al (2004) quoted lower UR rates in women with classical, inverted T and J incisions Landon study 2004 summary

STUDY 2 - I reviewed the full study (Additional information can found on ICAN's white papers: http://www.ican-online.org/resources/white_papers/wp_suture.pdf

The impact of a single-layer or double-layer closure on uterine rupture☆
Emmanuel Bujold, MDa, Camille Bujold, OTa, Emily F. Hamilton, MDb, François Harel, MSca, Robert J. Gauthier, MDa

American Journal of Obstetrics and Gynecology Volume 186, Issue 6, Pages 1326-1330 (June 2002)

Received 28 September 2001; accepted 20 December 2001

Objective: Our purpose was to measure the impact of a single-layer or double-layer closure on uterine rupture at subsequent delivery.

Study Design: This is an observational cohort study of all women undergoing a trial of labor from 1988 to 2000 in a tertiary care center, after a single low transverse cesarean delivery. Factors most highly associated with uterine rupture were identified by using univariate regression analysis. Multivariate logistic regression analysis was used to adjust for selected confounding variables.

Results:

N=1980
The odds ratio for uterine rupture in women with a single-layer closure was 3.95 (95% CI, 1.35-11.49).

Uterine Closure:
     Single layer = 489
            defined as: entire thickenss of the uterine wall from decidua to visceral periteneum closed with a           single continuopus interlocking suture

    Double layer = 1491
                defined as: continuous interlocking suture through the myometrium and decidua followed by a              continuous imbricating second layer and finally, closure of the viseral peritoneum.

Suturing material:  chromic catgut was used in 97.9% of all women in this study.  Polygalatin 910 (Vicryl) was used in 2.1%

Uterine rupture definition: defect that involved entire thickness of the uterine wall, including overlying periteneum with extrusion  of intrauterine contents into the perineal cavity that required operative intervention.  Cases of uterine scar dehiscence were excluded.

Uterine rupture (total rate = 1.2%)
    single layer = 15/489 (3.1%)
    Double layer = 7/1491 (0.5% )

All patients with a uterine rupture had their prior uterine incision closed by using a chromic catgut in an imbricating Lembert or Connell's suture.

Factors for risk of uterine rupture (n= 23 total ruptures in the study)
    15 ruptures were in single layer sutures
    11 ruptures occured in women <24 months from their c-sections
    20 ruptures occured in women who had epidurals
    13 ruptures occured in women who had c-sections for ftp
    8 ruptures occured in women who were induced*
    15 ruptures occured in women who were given oxytocin

* the authors states that prostaglandins were seldom used for induction at their hospital.  Intercervical extra-amniotic Foley catheters were used for cervical ripening when needed.  Between 1988 and 2000, only 6 patiends with a previous c-section received intravaginal Prostaglandin E2 for cervical ripening (it did not state whether any of these women ruptured though)

Uterine dehiscence:
     Single layer: 9/123 cesareans (7.3%)
     Double layer: 10/324 cesareans (3.1%)

VBAC success:
    76.3% of women in the study

They controlled (statistically) for the possible affects of pitocin, epidural use, age and other potentially confounding variables. The conclusion drawn was that there was a significantly higher risk of uterine rupture in women who’d had a single-layer closure of the uterus in a prior cesarean.

Conclusion: A single-layer closure of the previous lower segment incision was the most influential factor and was associated with a 4-fold increase in the risk of uterine rupture compared with a double-layer closure. (Am J Obstet Gynecol 2002;186:1326-30.)

NOTES:
    - chromic catgut suturing was used in all cases of uterine rupture
    - continuous/running locked stitches were used
    - a delivery of less than 24 months from c-section was also a large factor in uterine rupture in this         study
    - Oxytocin/pitocin was used in most of the UR cases (14/23)
    - There were 162 women excluded due to imcomplete records.  They had NO URs and 2 cases of             asymptomatic uterine scar dehiscence
     - Study only done at 1 hospital rather than collecting data from several hospitals.

There were several Letters to the Editor of the American Journal of Obstetrics and Gynecology regarding this study.  Here are some of the comments:

reference: Am J Obstet Gynecol (2003) Vol 188 (1)

"I believe that the reason for their better outcome in the two-layer closure group has little to do with the number of layers in the closure, but rather that the second layer was closed with a nonlocking stitch. Almost as an afterthought in their discussion, the authors indicate that the second imbricating layer may cause “less vascular occlusion.” The running locking stitch, like figure-of-eight stitches, causes vascular occlusion within the area surrounded by suture. These stitches were designed for hemostasis. I believe that it is entirely possible that they lead to weaker uterine scars because of vascular occlusion leading to poor healing.

...that the strongest and most satisfactory uterine closure at the time of cesarean delivery resulted from simple interrupted surgical gut sutures. One of the reasons put forth by the author for his findings was less vascular occlusion caused by the simple interrupted sutures as opposed to the running locking sutures.
I believe that the uterus can be closed in a single layer, but this should be either simple interrupted sutures or a running nonlocking stitch.
Dwight P. Cruikshank MD"

Authors reply to that Letter to the Editor

"The suture material in use was almost always chomic catgu.  We had no examples of single-layer closure with interrupted sutures, nor were we able to find a study that examined rates of uterine dehiscence or uterine rupture with this type of closure.

To date, we have found no studies comparing the effect of continuous nonlocking vs continuous locking sutures on the lower uterine segment.

According to our results and htese hysterographic studies, we are led to believe that a continuous locking suture for the closure of the ueterus in a single layer is not the ideal closure for patients planning a future pregnancy and should be reserved for womne who are having a tubal ligation done with the cesarean section.

Emmanuel Bujold, MD, Emily F Hamilton, MD and Robert J. Gauthier, MD"

Safety of VBAC: results and interpretations of a recent study PART II

Let’s look at those results a little further!

Results of the study (post: Safety of VBAC results and interpretation of a recent study PART I)were also published in the New England Journal of Medicine on December 16, 2004 (Volume 351 No 25)

MATERNAL AND PERINATAL OUTCOMES ASSOCIATED WITH A TRIAL OF LABOR AFTER PRIOR CESAREAN DELIVERY

Instead of separating out VBAC after 1 c-section and after multiple c-sections, this study looked at the overall risk of uterine rupture in vbac attempts. 

Vaginal delivery was attempted by 17,898 women while 15,801 underwent elective repeated cesarean deliveries without labor.  Symptomatic uterine rupture occurred in 124 women who underwent a trial of labor (0.7%).

Hypoxic-ischemic encephalopathy occurred in no infants whose mothers underwent ERCS and in 12 infants born at term whose mothers underwent TOL.  7 of these hypoxic-ischemic encephalopathy followed uterine rupture (absolute risk: 0.46 per 1000 women undergoing trial of labor) including 2 neonatal deaths. 

UTERINE RUPTURE ACCORDING TO LABOR STATUS
Spontaneous labor (n=6682): 24 ruptures (0.4%)
Augmented labor (n=6009): 52 ruptures (0.9%)
Induced labor (n=4708): 48 ruptures (1.0%)
- With any prostaglandins, with or without oxytocin (n=926): 13 ruptures (1.4%)
  - With prostaglandins alone (n=227): 0 ruptures
  - With no prostaglandins (n=1691): 15 ruptures (0.9%)
  - With oxytocin alone (n=1864): 20 ruptures (1.1%)
  - Not classified (n=496): 0 ruptures

UTERINE RUPTURE ACCORDING TO INCISION TYPE
Low transverse incision (n=14,483): 105 ruptures (0.7%)
Low vertical incision (n=102): 2 ruptures (2.0%)
Unknown type of incision (n=3206): 15 ruptures (0.5%)
Classical, inverted T or J incision (n=105): 2 ruptures (1.9%)
Unclassified (n=2)

MATERNAL DEATH
Trial of Labor (n=17,898): 3 deaths (0.02%)
Elective Repeat Cesarean Delivery (n=15,801): 7 deaths (0.04%)

TERM PREGNANCIES WITH UTERINE RUPTURE (n=114)
Neonatal deaths = 2 (1.8%)

OVERALL FINDINGS:

There were 124 ruptures out of 17,898 women undergoing VBAC with 2 neonatal deaths resulting.

The rate of uterine rupture was 0.4% in women who labored spontaneously.

The overall rate of uterine rupture was 0.7% in women who had a low tranverse incision (induced/augmented and spontaneous labors).

STUDY REFERENCE:

Volume 351:2581-2589  December 16, 2004  Number 25

Maternal and Perinatal Outcomes Associated with a Trial of Labor after Prior Cesarean Delivery

Mark B. Landon, M.D., John C. Hauth, M.D., Kenneth J. Leveno, M.D., Catherine Y. Spong, M.D., Sharon Leindecker, M.S., Michael W. Varner, M.D., Atef H. Moawad, M.D., Steve N. Caritis, M.D., Margaret Harper, M.D., Ronald J. Wapner, M.D., Yoram Sorokin, M.D., Menachem Miodovnik, M.D., Marshall Carpenter, M.D., Alan M. Peaceman, M.D., Mary Jo O'Sullivan, M.D., Baha Sibai, M.D., Oded Langer, M.D., John M. Thorp, M.D., Susan M. Ramin, M.D., Brian M. Mercer, M.D., Steven G. Gabbe, M.D., for the National Institute of Child Health and Human Development Maternal–Fetal Medicine Units Network

Safety of VBAC: results and interpretations of a recent study PART I

OBJECTIVE:
To determine whether the risk for uterine rupture is increased in women attempting vaginal birth after multiple cesarean deliveries (vbaMc) vs the risk of a vaginal birth attempt after one cesarean delivery (vba1c).

TERMINOLOGY

• VBAC = vaginal birth after cesarean
• VBA1C = vaginal birth after 1 cesarean
• VBAMC = vaginal birth after multiple (2 or more) cesareans
• Uterine Rupture  (UR) = disruption of the uterine muscle and visceral peritoneum or a uterine muscle separation.
• TOL = trial of labor
• ERCS = elective repeat cesarean section

METHODS:

• Results obtain from 19 academic medical centers
• 45,988 women with cesarean history and single gestations included:
• 17,898 (39%) underwent TOL
• 15,801 (34%) had elective cesareans
• 9,013 (20%) had indications for repeat cesarean
• 3,276 (7%) presented in early labor; intentions unknown

TOL group:

• 16,915 (95%) had 1 prior cesarean
• 975 (5%) had more than 1 cesarean:
• 871 (89%) had 2 cesareans
• 84 (9%) had 3 cesareans
• 20 (2%) with 4 cesareans

RESULTS

Uterine Rupture rate:

• 0.7% VBA1C  (115/16,915)
• 0.9% VBAMC (9/975)
• Successful VBACS
• 74% VBA1C (12,490/16,915)
• 66% VBAMC (648/975)
• Increased rate of endometriosis, hysterectomy, NICU admission and transfusion multiple cesarean group

This study was large enough to detect a 3 fold increase in rupture rates
between the 2 groups

There is no statistical difference in the rate of uterine rupture between groups

In the VBA1C group (n=16,915), with 115 uterine ruptures, there were 12 term neonatal deaths (0.08%).

In the VBAMC group (n=975) with 9 uterine ruptures, there was 1 term neonatal death. (0.1%)

In the ERCS group (n=6,035), there was 1 term neonatal death (0.02%)

It is not clear whether uterine rupture was the reason for death in the VBA1C and VBAMC group.

RISK FACTORS FOR UTERINE RUPTURE

• Oxytocin augmentation
• 25% mutiple grp
• 32% single grp
• Labor induction
• 24% multiple grp
• 26% single grp
• Less than 2 years from previous cesarean
• 27% multiple grp
• 25% single grp

WHAT SHOULD THE EFFECTS OF THIS STUDY BE?

• American College of Obstetrics and Gynecology (ACOG) should update VBAC recommendations.
• VBAMC should be allowed
• Women should be counseled about their birthing options with accurate information on risks/benefits of VBAC and ERCS

CONCLUSIONS

• VBAMC recommendation/allowance not likely to happen due to ingrained “perceived” high risk
• Poorly designed previous studies
• Malpractice suits, etc
• Study needs to separate out:
  • single and double layer suturing

STUDY REFERENCE:

Obstetrics & Gynecology 2006;108:12-20
© 2006 by The American College of Obstetricians and Gynecologists
ORIGINAL RESEARCH

Risk of Uterine Rupture With a Trial of Labor in Women With Multiple and Single Prior Cesarean Delivery

Mark B. Landon, MD1, Catherine Y. Spong, MD20, Elizabeth Thom, PhD21, John C. Hauth, MD2, Steven L. Bloom, MD3, Michael W. Varner, MD4, Atef H. Moawad, MD5, Steve N. Caritis, MD6, Margaret Harper, MD, MS7, Ronald J. Wapner, MD8, Yoram Sorokin, MD9, Menachem Miodovnik, MD10, Marshall Carpenter, MD11, Alan M. Peaceman, MD12, Mary J. O’Sullivan, MD13, Baha M. Sibai, MD14, Oded Langer, MD15, John M. Thorp, MD16, Susan M. Ramin, MD17, Brian M. Mercer, MD18, Steven G. Gabbe, MD for the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network19 *

From the Departments of Obstetrics and Gynecology at the 1Ohio State University, Columbus, Ohio; 2University of Alabama at Birmingham, Birmingham, Alabama; 3University of Texas Southwestern Medical Center, Dallas, Texas; 4University of Utah, Salt Lake City, Utah; 5University of Chicago, Chicago, Illinois; 6University of Pittsburgh, Pittsburgh, Pennsylvania; 7Wake Forest University, Winston-Salem, North Carolina; 8Thomas Jefferson University, Philadelphia, Pennsylvania; 9Wayne State University, Detroit, Michigan; 10University of Cincinnati, Cincinnati, Ohio, and Columbia University, New York, New York; 11Brown University, Providence, Rhode Island; 12Northwestern University, Chicago, Illinois; 13University of Miami, Miami, Florida; 14University of Tennessee, Memphis, Tennessee; 15University of Texas Health Science Center at San Antonio, San Antonio, Texas; 16University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; 17University of Texas Health Science Center at Houston, Houston, Texas; 18Case Western Reserve University, Cleveland, Ohio; 19Vanderbilt University, Nashville, Tennessee; and 20the National Institute of Child Health and Human Development, Bethesda, Maryland; and 21the George Washington University Biostatistics Center, Washington, DC.