Trial of Labor after Cesarean (TOLAC)

In 2016, the US cesarean delivery rate was 31.9%. With ever increasing volumes of cesarean delivery, TOLAC has become a popular option for patients desiring vaginal delivery. On today’s episode, we examine TOLAC and share some counseling pointers in thinking about your patient. ACOG PB 205 is the requisite reading for the topic.

While there are no RCTs comparing TOLAC to planned cesarean, the relative benefits are easy to see: there is less recovery time, the patient avoids major surgery, and the potential sequelae of complications from major surgery — worsened bleeding, more opportunity for infection, more risk of complications requiring additional procedures. However, TOLAC is not without risk. We primarily counsel with respect to uterine rupture. Evaluations of “rupture” though have varied in the literature; it’s important to keep a discerning eye, as what is classified as rupture in some series is very different than what is in others. ACOG suggests the rate of uterine rupture in a patient with one low transverse cesarean delivery is around 0.5 - 0.9 %. Otherwise, maternal risks are fairly equal. Neonatal risks are also considered fairly equal, though with some increased risk associated with TOLAC.

ACOG PB 205

ACOG PB 205

We can think about patients who should be counseled against TOLAC:

  • Those at high risk of uterine rupture: ie. those with classic uterine incision, T-incision, prior uterine rupture, or extensive prior uterine fundal surgery like a myomectomy.

  • Women who are not otherwise candidates to have vaginal deliveries: ie. previa.

  • Women who desire homebirth: While ACOG does not definitely say that you cannot TOLAC in this instance, if you don’t access to emergency cesarean delivery, it is recommended that these patients have a discussion regarding the hospitals resources and possibly referral to a hospital that does have access to emergency cesarean delivery.

We can also consider patients for whom there may be a question of whether TOLAC is appropriate:

  • Low vertical incision? 

    1. Few studies, but those that have looked at them have shown similar rates of vaginal deliveries as low transverse. Can consider TOLAC!

  • Twins? 

    1. Studies show similar rates of successful VBAC in twins as in singleton gestations 

  • Obesity 

    1. Unfortunately, higher BMI seems to have an inverse relationship with success of VBAC. 85% of normal weight women achieve VBAC while only 65% of morbidly obese women do. However, morbidly obese women also can have more complications with an elective repeat cesarean, so counseling should be individualized

  • Induction and augmentation of labor 

    1. Mechanical dilation can be used - ie. cervical foley 

    2. Misoprostol has been shown to have increased risk of uterine rupture, so should not be used in term patients who have had c/s or other major uterine surgery for induction 

    3. However, in women undergoing second trimester labor inductions (ie. for missed abortion, induction of labor for stillbirths), use of prostaglandins have shown similar results in women who have had scars on their uterus and those without; so these women can still have prostaglandins, especially because no fetal considerations 

  • What if they’ve had a uterine rupture? 

    • If the site of rupture or dehiscence is in the lower part of the uterus, their risk of uterine rupture in labor is 6%. If it is in the upper segment of the uterus, the rate of dehiscence in labor is up to 32%. While there is no high quality data to guide this, recommendations are generally for subsequent pregnancies to be delivered by cesarean between 36-37 weeks.

Counseling should be individualized, and the MFMU has excellent calculators to help guide you and your patients to a decision about TOLAC:

(not in labor) https://mfmunetwork.bsc.gwu.edu/PublicBSC/MFMU/VGBirthCalc/vagbirth.html

(at admission) https://mfmunetwork.bsc.gwu.edu/PublicBSC/MFMU/VGBirthCalc/vagbrth2.html

Considerations for Planned Singleton Breech Vaginal Delivery

Today’s episode dives more into the realm of expert opinion rather than hard science, and we hope some of our listeners will share their own experiences and criteria for offering planned breech labor!

ACOG CO 745, in addition to PB 161 on external cephalic version, deal with this topic, but there is much variation in the literature available. In particular, international guidelines on this topic are rather variable. The ObG Project has a great summary and links to these varying resources that is worth checking out.

There are particular risks to breech labor, and experienced provider hands are necessary, which is why almost 90% of planned term breech birth in the USA is performed by cesarean section. The 2000 Term Breech Trial, a multicenter randomized trial, noted perinatal morbidity and mortality was overall reduced with planned cesarean delivery than with planned vaginal delivery of term breech (1.6% vs 5.0%), with no differences in reported maternal morbidity or mortality. Follow up studies to the Term Breech Trial, however, have noted no differences in maternal or neonatal outcomes at 2 years.

Additional studies performed since this time have been mixed. While some prospective studies demonstrated excellent maternal and neonatal outcomes, both short- and long-term, they utilized very strict criteria and protocols for the selection of candidates offered a trial of breech labor. Cohort studies of breech birth in general populations demonstrates at least short-term risk of neonatal morbidity, including birth injury, nerve injury, and need for assisted ventilation. This risk is present with any trial of breech labor, including if intrapartum cesarean is performed, versus planned cesarean delivery.

Below is a sample protocol based on some of these studies with stricter inclusion criteria. We recognize there is likely some significant debate to be had on these criteria, and in particular clinical scenarios, so be sure to discuss with experienced obstetricians in your area as well as check your hospital’s own breech birth protocol.

(c) CREOGs over Coffee, 2019. Adapted from Hofmeyr/UpToDate, 2019.

Finally, intrapartum management should proceed according to usual obstetric practice. However with breech presentations, providers should closely consider a number of factors outlined below. Notably, these factors are largely based on expert opinion and guidelines from international societies.

  • Avoidance of early amniotomy, and preference for spontaneous rupture of membranes.

  • The progress of labor in the active phase, and progress of descent during active pushing. 

    • Cesarean delivery should be recommended with a protracted labor course, particularly in the active phase, as this may be indicative of fetopelvic disproportion. 

    • Use of oxytocin in the active phase of labor is discouraged.

    • With the achievement of full cervical dilation, the breech should reach the pelvic floor.

    • Passive descent should not be permitted for more than 90 minutes after achieving full cervical dilation.

    • With onset of active pushing, delivery by cesarean should be considered if the infant has not delivered within 30-60 minutes.

Preterm Labor and PPROM

Today we talk about the routine management of PPROM and PTL. We’ve prepared a little chart that we hope is handy for both teaching and learning! Be sure to also check out ACOB PB 171 and PB 188. For some primary literature, check out the BEAM trial on magnesium sulfate, the most recent Cochrane review on steroid administration, the ALPS trial for Antenatal Late Preterm Steroid administration, and the RCT demonstrating benefit to latency antibiotics in PPROM.

(c) CREOGS over Coffee, 2019

We also use the podcast to highlight a number of controversies, differing practice patterns, or areas of new and active research in these clinical topics (with help from our friends at the ObG Project!)

  • Delivery timing: A 2017 Cochrane review suggested better neonatal outcomes with expectant management of PPROM to 37 weeks, convincing enough to have the Royal College of Obstetrics and Gynecology to change their clinical practice guideline to allow expectant management to 37’0.

  • Administration of Corticosteroids: The ObG Project gives a great summary on when to administer betamethasone. In summary:

    • Between 24-34 weeks in all cases of PPROM and in PTL if delivery is expected within 7 days.

    • A single rescue course should be administered if it has been > 14 days since the last course, and delivery is again expected within the subsequent 7 days.

    • Between 34-36’6 weeks if PPROM or PTL occurs, no prior steroids have been administered, and delivery is expected within the subsequent 7 days.

  • Periviability: The management of periviable PPROM is managed very differently by institution, as resources and optimal management strategies remain to be identified. Protocols and policies should be arranged in accordance with the individual obstetrics and neonatology departments. Ideally, counseling for patients experiencing periviable PTL and PPROM should be performed in an interdisciplinary fashion.

  • Outpatient Management of PPROM: There have a few retrospective studies, the most recent of which came from a large series out of France and received some press attention, suggesting that outpatient management may be appropriate in select candidates. That said, this is definitely NOT the standard of care at this time; inpatient management of PPROM is still the standard set forth by ACOG in the absence of larger, prospective studies.

Cardiotocography/EFM Part II: Management

Today we are back with our midwifery colleagues Linda Steinhardt and Liz Kettyle, who shepherd us through the management of cardiotocography in labor.

We start this episode by quickly reviewing definitions, and defining categories of tracings, reviewed below:

Copyright UpToDate

Recall that category I tracings virtually exclude fetal acidemia, while category III tracings are associated with acidemia 25% of the time, but also have higher risk of cerebral palsy, neurologic injury, or fetal death. That said, the positive predictive value for bad outcomes of CTG is overall poor.

We review a number of scenarios and resuscitative measures for category II and III tracings. However, much of this episode draws on the 2013 Clark et al. article to describe the management of category II tracings. The algorithm is below:

Clark et al. (AJOG 2013)

Interpreting Cardiotocography/EFM Part I: Definitions

Today we take a break from STIs to jump back into obstetrics, and are joined by two very special guests: Liz Kettyle and Linda Steinhardt, both of whom are certified nurse midwives (CNMs) and clinical educators at the Warren Alpert Brown School of Medicine.

ACOG PB 106 (membership required) forms the basis for this episode and in a future episode, we will discuss management of cardiotocography (CTG). Also, for a recent article surrounding the naming of CTG vs. EFM vs. all the other names for this technology, check out a recent AJOG article on its now 50-year history.

We also are using some special sound effects for these episodes! As you listen to the various sounds for different types of decelerations, keep in mind that the higher-pitched sound represents a contraction pattern, and the lower-pitched sound represents the fetal heart rate response.