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  1. 1. Trial of Labor After Previous Cesarean Delivery “TOLAC” The term trial of labor refers to a trial of labor in women who have had a previous cesarean delivery, regardless of the outcome. TOLAC MAY LEAD TO SUCCESFUL VBAC September 2010
  2. 2. ACOG # 115 2010 <ul><li>Validate/Reference well performed studies & present a range of data (+/-) emphasizing that it may be reasonable to expand the CANDIDATE POOL. </li></ul><ul><li>Extreme caution should STILL be exercised when considering “ additional factors “ @ term which may influence the success or failure of VBAC </li></ul><ul><li>THE MOST CLINICALLY USEFUL INFORMATION IN THE NEW BULLETIN </li></ul><ul><li>TOLAC COUNSELING CALCULATOR </li></ul><ul><li>MORTALITY /MORBIDITY % tge TABLES </li></ul>
  3. 3.   The American College of Obstetricians and Gynecologists guidelines for identifying women who are potential candidates for TOLAC NOW include the following: <ul><li>WHO ARE NEW TOLAC CANDIDATES </li></ul><ul><li>TWO previous low transverse uterine incisions Ok </li></ul><ul><li>Twins Ok </li></ul><ul><li>ECV Ok </li></ul><ul><li>EGA > 40 weeks Ok </li></ul><ul><li>One Low vertical Ok </li></ul><ul><li>Suspected Macrosomia alone Ok </li></ul><ul><li>“ Informed induction” Ok however NO prostaglandins followed by oxytocin. ( Foley bulb followed by pitocin ) </li></ul><ul><li>Undocumented scar with out history suggesting classical c/s </li></ul><ul><li>ACOG PRACTICE BULLETIN AUGUST Number 115, 2010 </li></ul>
  4. 4. Contraindications for VBAC <ul><li>Prior classical or T-shaped uterine incision or extensive transfundal uterine surgery (eg, myomectomy) </li></ul><ul><li>Previous uterine rupture (the frequency of repeat rupture varies from 6 to 32 percent , respectively if the lower uterine segment or the upper segment was the site of the initial rupture) </li></ul><ul><li>No Cytotec </li></ul><ul><li>Medical or obstetrical complications that preclude vaginal birth (eg, placenta previa) </li></ul><ul><li>Inability to immediately perform emergency cesarean delivery due to factors related to the facility, surgeon, anesthesia, or nursing staff </li></ul><ul><li>Two or more prior uterine scars and no prior vaginal deliveries . 2010 REMOVED two previous c/s and remained silent regarding previous vaginal delivery </li></ul><ul><li>ACOG VBAC Bulletin # 54 JULY 2004 / 2010 #115 </li></ul>
  5. 5. Uterine Rupture By Incision Location <ul><li>The rate of rupture reported by incision location is: </li></ul><ul><li>Classical (4 to 9 %) </li></ul><ul><li>T-shaped (4 to 9 %) </li></ul><ul><li>Low vertical (1 to 7 %) </li></ul><ul><li>1 Low transverse ( 0.7 to 0.9 %) </li></ul><ul><li>2 Low transverse ( 0.9-1.8 % ) </li></ul>
  6. 6. 2 previous C /S C andidates but C ounsel C arefully <ul><li>Two large studies referenced by ACOG, with sufficient size to control for confounding variables, reported on the risks for women with two previous cesarean deliveries undergoing TOLAC. </li></ul><ul><li>One study found no increased risk of uterine rupture (0.9% versus 0.7%) in women with one versus multiple prior cesarean deliveries , whereas the other noted a risk of Uterine Rupture that increased from 0.9% to 1.8% ( 2X ) in women with one versus two prior cesarean deliveries </li></ul><ul><li>Both studies reported some increased risk in morbidity among women with more than one prior cesarean delivery although the absolute magnitude of the difference in these risks was relatively small (eg, 2.1% versus 3.2%) composite major morbidity in one study </li></ul>Obstet Gynecol 2006;108:12–20. Am J Obstet Gynecol2005;192:1223–8
  7. 7. 2 PREVIOUS C/S ACOG 2010 <ul><li>The chance of achieving VBAC appears to be similar for women with one or more than one cesarean delivery. </li></ul><ul><li>Given the overall data, it is reasonable to consider women with two previous low transverse cesarean deliveries to be candidates for TOLAC </li></ul><ul><li>Do Not forget to Counsel based on the combination of other factors that affect the probability of achieving a successful VBAC . </li></ul>
  8. 8. Maternal Factors Associated VBAC SUCCESS <ul><li>Young maternal age </li></ul><ul><li>Increased height </li></ul><ul><li>Body mass index <30 kg/m2 </li></ul><ul><li>Non-Hispanic white ethnicity </li></ul><ul><li>Favorable cervix &/Or Spontaneous Labor </li></ul><ul><li>Gestational age <40 weeks . </li></ul><ul><li>Birthweight <4000 g </li></ul><ul><li>The rate of success increases as the number of prior VBAC successes increases </li></ul>
  9. 9. Maternal Factors Associated VBAC FAILURE <ul><li>Recurrent indication for initial cesarean delivery </li></ul><ul><li>Increased maternal age </li></ul><ul><li>Non-white ethnicity </li></ul><ul><li>Gestational age greater than 40 weeks </li></ul><ul><li>Maternal obesity </li></ul><ul><li>Preeclampsia </li></ul><ul><li>Short interpregnancy interval </li></ul><ul><li>Increased neonatal birth weight </li></ul>
  10. 10. TOLAC/VBAC SUCCESS COUNSELING CALCULATOR 2010 ACOG <ul><li>A model was developed specifically for women undergoing TOLAC at term with one prior low transverse cesarean delivery incision, singleton pregnancy, and cephalic fetal presentation. </li></ul><ul><li>This model may have utility for patient education and counseling for those considering TOLAC at term </li></ul><ul><li>http://www.bsc.gwu.edu/mfmu/vagbirth.html </li></ul>
  11. 11. VAGINAL BIRTH AFTER CESAREAN Height & weight optional; enter them to automatically calculate BMI Maternal age Height (range 54-80 in.)   Weight (range 80-310 lb.)   Body mass index (BMI, range 15-75) African-American? Hispanic? Any previous vaginal delivery? Any vaginal delivery since last cesarean? Indication for prior cesarean of arrest of dilation or descent?
  12. 12. SAMPLE PATIENT <ul><li>5 FOOT 3 INCHES </li></ul><ul><li>225 LBS </li></ul><ul><li>HISPANIC </li></ul><ul><li>NO PREVIOUS VAGINAL DELIVERY </li></ul><ul><li>PREVIOUS C/S FOR CPD </li></ul><ul><li>Predicted chance of vaginal birth after cesarean:   24.5% 95% CI: [ 21.3% , 28.1% ] </li></ul>
  13. 13. CONSIDER THE RESULTS Consider additional Information <ul><li>It is designed for educational use and is based on a population of women who received care at the hospitals within the MFMU Network. Responsibility for its correct application is accepted by the end user. </li></ul><ul><li>&quot;Development of a nomogram for prediction of vaginal birth after cesarean delivery,&quot; Obstetrics and Gynecology, volume 109, pages 806-12, 2007. </li></ul>
  14. 14. ACOG/TOLAC CALCULATOR ACOG 2010 <ul><li>Although there is no universally agreed on discriminatory point, evidence suggests that women with at least </li></ul><ul><li>60–70% chance of VBAC </li></ul><ul><li>Have equal or less maternal morbidity when they undergo TOLAC than women undergoing elective repeat cesarean delivery </li></ul>
  15. 15. ACOG/TOLAC CALCULATOR ACOG 2010 <ul><li>Less than or Equal to 60% probability TOLAC RISK outweigh the potential benefit </li></ul><ul><li>Failed VBAC is associated with a greater chance of NEONATAL AND MATERNAL MORBIDITY than woman undergoing elective repeat cesarean delivery </li></ul>
  16. 16. The MFMU Cesarean Registry: Prospective study with > 14,500 vbac attempts <ul><li>The overall VBAC success rate in obese women (BMI > or = 30) was lower (68.4%) than in non obese women (79.6%) (P < .001) </li></ul><ul><li>When combined with induction and lack of previous vaginal delivery , successful VBAC occurred in only 44.2% of cases. </li></ul><ul><li>Am J Obstet Gynecol 2005 Sep;193(3 Pt 2):1016-23 </li></ul>
  17. 17. Success for VBAC by History <ul><li>PREVIOUS VAGINAL DELIVERY </li></ul><ul><li>Yes / 85% success No / 60% success </li></ul><ul><li>PREVIOUS VBAC DELIVERY </li></ul><ul><li>Yes / 85% success No / 65% success </li></ul><ul><li>CERVIX 4 CM ON ADMISSION </li></ul><ul><li>Yes / 85 % success No / 65% success </li></ul><ul><li>SPONTANEOUS LABOR 80% success </li></ul>Am J Obstet Gynecol 2005; 193:1016
  18. 18. Success for VBAC by history <ul><li>Previous non recurring indication 75-85 % </li></ul><ul><li>All pts with DYSTOCIA as indication 50-80% </li></ul><ul><li>Latent phase C/S (4cm or less) 80% </li></ul><ul><li>Active phase C/S ( 5 to 9 cm ) 70% </li></ul><ul><li>Second stage C/S (10 & pushing) 10% </li></ul><ul><li>ACOG VBAC BULLETIN # 54 2004 </li></ul>
  19. 19. Increase BMI > 39 = Increased risk <ul><li>A BMI > 39 was associated with greater composite maternal morbidity and neonatal injury compared with elective repeat cesarean delivery </li></ul><ul><li>Increasing BMI was directly associated with failed trial of labor after previous cesarean delivery </li></ul><ul><li>BMI > 39 TOLAC WAS ASSOCIATED WITH </li></ul><ul><li>5 X risk of uterine rupture (2.1% vs 0.4%), </li></ul><ul><li>5 X risk of neonatal injury (1.1% vs 0.2%) </li></ul><ul><li>2 X risk of Maternal Morbidity (7.2% versus 3.8%) </li></ul>Obstet Gynecol. 2006 Jul;108(1):125-33 MFMU
  20. 20. VBAC Safety and Success AT OR Beyond 40 weeks of gestation <ul><li>There is a 4% increased risk for a failed VBAC @ 35 % @ 41 weeks vs 31 % @ 40 weeks </li></ul><ul><li>~ 65 % successful VBAC @ 41 weeks </li></ul><ul><li>The risk of overall maternal morbidity IS not clinically or statistically significant when comparing after 41 vs 40 weeks (2.7% @ 41 weeks compared with 2.1% @ 40 0/7 weeks). </li></ul>Obstet Gynecol. 2005 Oct;106(4):700-6
  21. 21. 40 WEEKS OR GREATER <ul><li>“ Although chances of success may be lower( 4%) in more advanced gestations, gestational age of greater than 40 weeks alone should not preclude TOLAC.” Use calculator to help you decide </li></ul><ul><li>Be cautious and include OTHER PERTINENT risk factors for VBAC failure or increased risk for uterine rupture with TOLAC in this situation such as </li></ul><ul><li>Interdelivery interval, EFW ( > 3600 grams) , & Bishop score, Previous C/S indication, </li></ul><ul><li>ACOG 2010 #115 </li></ul>
  22. 22. 4000 GRAMS MACROSOMIA <ul><li>Some limited evidence also suggests that the uterine rupture rate is increased (relative risk 2.3, P<.001) for women undergoing TOLAC without a prior vaginal delivery and neonatal birth weights greater than 4,000 g. </li></ul><ul><li>It remains appropriate for health care providers and patients to consider past and predicted birth weights (ie sono for efw if suspicious) when making decisions regarding TOLAC, but suspected macrosomia alone should not preclude the possibility of TOLAC . </li></ul>
  23. 23. TWINS <ul><li>Women with twin gestations had a similar chance of achieving VBAC as women with singleton gestations and did not incur any greater risk of uterine rupture or maternal or perinatal morbidity. </li></ul><ul><li>Women with one previous cesarean delivery with a low transverse incision, who are otherwise appropriate candidates for twin vaginal delivery, may be considered candidates for TOLAC. </li></ul>
  24. 24. INDUCTION/AUGMENTATION <ul><li>Induced labor is less likely to result in VBAC than spontaneous labor, ESPECIALLY with an unfavorable cervix. </li></ul><ul><li>Therefore, selecting women most likely to give birth vaginally while avoiding sequential use of prostaglandins and oxytocin appears to have the lowest risks of uterine rupture. </li></ul><ul><li>The varying outcomes of available studies and small absolute magnitude of the risk reported in those studies support that oxytocin augmentation may be used in patients undergoing TOLAC. 1% risk of rupture with oxytocin augmentation </li></ul><ul><li>Induction utilizing mechanical dilation ( Foley Bulb distended to 40 ml more effective or @ least as effective as Cytotec in RCT) may be an option for TOLAC candidates with an unfavorable cervix . </li></ul>
  25. 25. COUNSELING RISK OF UTERINE RUPTURE <ul><li>Spontaneous labor 0.9% 1 c/s vs 1.8% for 2 </li></ul><ul><li>Induced TOLAC 1% - 2.4% </li></ul><ul><li>Pitocin Augmented 1% </li></ul>Am J Obstet Gynecol 1999;181:882 N Engl J Med 2004;351:2581–9 N Engl J Med. 2001 Jul 5;345(1):3-8. ACOG Number 115, August 2010
  26. 26. IS THERE A role of UTERINE CLOSURE in the risk of uterine rupture NOT CONSISTENTLY DEMONSTARTED AS A RISK FACTOR AND NOT INCLUDED BY ACOG AS A RISK FACTOR <ul><li>Prior single-layer closure may be associated with a two fold or higher risk of uterine rupture compared with double-layer closure. Single-layer closure should be avoided in women who could contemplate future vaginal birth after cesarean delivery. </li></ul>Bujold E Obstet Gynecol. 2010 Jul;116(1):43-50 Bujold E Am J Obstet Gynecol. 2002;186(6):1326-30
  27. 27. Controversy Regarding Closure of the Uterus <ul><li>Only one Author ( Bujold E) has demonstrated an increased risk of uterine rupture with single vs two layer closure in two separate retrospective studies. </li></ul><ul><li>No proven physiologic/biologic models. Inclusion of endometrium in animal studies may be associated with adenomyosis and interfere with scar formation ; However Never been demonstrated to effect scar integrity. </li></ul><ul><li>Hypoxia and/Or vascular occlusion may result in poor tissue healing? Locking vs Running uterine closure? Or Multiple hemostatic figure of 8 sutures? Never been demonstrated to effect scar integrity . </li></ul>
  28. 28. Short Interdelivery Interval Time elapsed from previous delivery date to current TOLAC <ul><li>Multiple studies have demonstrated that an Interdelivery interval < or = to 18 months may be associated with a two fold or higher risk of uterine rupture during TOLAC. Furthermore it appears that a shorter Interdelivery interval is associated with a greater than two fold risk of rupture. </li></ul>Obstet Gynecol. 2010 May;115(5):1003-6 Obstet Gynecol. 2007 Nov;110(5):1075-82. Am J Obstet Gynecol. 2002 ;187(5):1199-202 Obstet Gynecol. 2001 Feb;97(2):175-7 Am J Obstet Gynecol 2000;183:1180–1183
  29. 29. If Uterine Rupture Occurs with Immediately Available Team <ul><li>Risk of HIE 10-11% @ worse case estimate </li></ul><ul><li>(95% confidence interval, 1.8–10.6%) </li></ul><ul><li>Neonatal death ~ 5% @ worse case estimate </li></ul><ul><li>(95% CI, 0–4.2% ) </li></ul><ul><li>Maternal risk of ~ 10 % for Transfusion </li></ul><ul><li>5% risk for TAH ; </li></ul><ul><li>30 % for TAH with Catastrophic Rupture </li></ul><ul><li>ACOG Number 115, August 2010 </li></ul><ul><li>N Engl J Med 2001;345:3-8 </li></ul>
  30. 30. Maternal Risks ERCD (%) TOLAC (%) One CD Two CDs Endometritis 1.5–2.1 2.9 3.1 Operative injury 0.42–.6 0.4 0.4 Blood transfusion 1–1.4 0.7–1.7 3.2 Hysterectomy 0–0.4 0.2–0.5 0.6 Uterine rupture 0.4–0.5 0.7–0.9 0.9–1.8 Maternal death 0.02–0.04 0.02 0 ACOG Number 115, August 2010
  31. 31. Neonatal risk <ul><li>Short term respiratory transitional needs ~ 2 x as high with ERCD vs successful VBAC </li></ul><ul><li>Hyperbilirubinemia ~ 2 x as high with ERCD vs successful VBAC </li></ul><ul><li>Neonatal morbidity is higher in the setting of a failed TOLAC than with successful VBAC </li></ul><ul><li>( therefore < 60% success not recommended for TOLAC) </li></ul><ul><li>Perinatal mortality is higher ( includes stillbirth) with TOLAC vs ERCD ; however the absolute risk is ~ 1/10 of 1% </li></ul><ul><li>ACOG Number 115, August 2010 </li></ul><ul><li>N Engl J Med 2004;351:2581–9 </li></ul>
  32. 32. Neonatal Risks ERCD (%) TOLAC (%) IUFD 37–38 weeks 0.08 0.38 IUFD 39 weeks or greater 0.01 0.16 HIE 0–013 0.08 Neonatal death 0.05 0.08 NS Perinatal death 0.01 0.13 HYPOXIA Neonatal admission 6.0 6.6 NS Respiratory morbidity 1–5 0.1–1.8 Transient tachypnea 6.2 3.5 Hyperbilirubinemia 5.8 2.2
  33. 33. DOCUMENTATION MANDATORY <ul><li>Documentation of counseling and the management plan should be included in the medical record. </li></ul><ul><li>Potential benefits and risks ( % ) of both TOLAC and elective repeat cesarean delivery should be discussed and documented. </li></ul><ul><li>The VBAC SUCCESS CALCULATOR AND MATERNAL /NEONATAL RISK TABLES provided by ACOG facilitate a STANDARDIZED discussion that is patient specific and ENDORSED by ACOG. </li></ul><ul><li>“ After counseling, the ultimate decision to undergo TOLAC or a repeat cesarean delivery should be made by the patient in consultation with her healthcare provider”. </li></ul>
  34. 34. Dr Montgomery Recommends <ul><li>DOCUMENT COUNSELING WIH QUOTED RISK/BENEFIT % tges </li></ul><ul><li>TOLAC CALCULATOR : No < 60 /60-69 Offer/ 70 or > Recommend </li></ul><ul><li>Additionally consider interdelivery interval during antenatal calculation </li></ul><ul><li>DO RECOMMEND For a patient who has requested TOLAC a scheduled repeat cesarean section by 41 0/7 weeks with success calculated @ 70% For a patient who has requested TOLAC a scheduled repeat cesarean section by 40 0/7 weeks with success calculated @ < 70% </li></ul><ul><li>REMEMBER EFW & modified Bishop Score as you approach 38 weeks </li></ul><ul><li>Thoroughly counsel about induction or augmentation taking into account additional factors associated with failure and/or increased risk. </li></ul><ul><li>DO RECOMMEND SCHEDULED REPEAT CESAREAN SECTION @ 39 WEEKS FOR PATIENTS WHO DECLINE TOLAC; Due to the documented increased risk of IUFD after 39 weeks. </li></ul><ul><li>DO NOT recommend TOLAC for patients with a history of failure of descent (previously dilated to 10 cm) >/= to 85 % will have a failed VBAC Schedule C/S @ 39 0/7 weeks for these patients. </li></ul><ul><li>DO NOT recommend TOLAC For patients with a BMI of 39 or greater. Schedule C/S @ 39 0/7 weeks for these patients. </li></ul>