A randomized trial of Foley balloon induction of labor trial in nulliparas (FIAT-N)

Accepted Manuscript A Randomized Trial of Foley Balloon Induction of Labor Trial in Nulliparas (FIAT-N) Katherine A. Connolly, MD, Katherine S. Kohari, MD, Patricia Rekawek, MD, Ms. Brooke S. Smilen, Meredith R. Miller, MPH, Erin Moshier, MS, Stephanie H. Factor, MD, MPH, Joanne L. Stone, MD, Angela T. Bianco, MD PII:

S0002-9378(16)00526-3

DOI:

10.1016/j.ajog.2016.03.034

Reference:

YMOB 11013

To appear in:

American Journal of Obstetrics and Gynecology

Received Date: 3 March 2016 Accepted Date: 17 March 2016

Please cite this article as: Connolly KA, Kohari KS, Rekawek P, Smilen BS, Miller MR, Moshier E, Factor SH, Stone JL, Bianco AT, A Randomized Trial of Foley Balloon Induction of Labor Trial in Nulliparas (FIAT-N), American Journal of Obstetrics and Gynecology (2016), doi: 10.1016/j.ajog.2016.03.034. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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TITLE: A Randomized Trial of Foley Balloon Induction of Labor Trial in Nulliparas (FIAT-N)

AUTHORS:

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Katherine A. CONNOLLY, MD1 Katherine S. KOHARI, MD2 Patricia REKAWEK, MD1

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Ms. Brooke S. SMILEN1

Erin MOSHIER, MS3 Stephanie H. FACTOR, MD, MPH1,4 Joanne L. STONE, MD1

INSTITUTIONS: 1

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Angela T. BIANCO, MD1

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Meredith R. MILLER, MPH1

Icahn School of Medicine at Mount Sinai, Department of Obstetrics, Gynecology and

Yale School of Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences,

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2

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Reproductive Science, New York, NY

New Haven, CT 3

Icahn School of Medicine at Mount Sinai, Department of Population Health Science and Policy,

New York, NY 4

Icahn School of Medicine at Mount Sinai, Department of Medicine, New York, NY

DISCLOSURE STATEMENT: The authors report no conflict of interest.

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FUNDING: None CLINICAL TRIAL REGISTRATION: This trial is registered at clinicaltrials.gov (NCT02098421)

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PRESENTATIONS: This abstract was presented at the 36th Society for Maternal Fetal Medicine Annual Pregnancy Meeting on February 5, 2016 in Atlanta, Georgia (Abstract #43, # SMFM-FT-

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16-32) CORRESPONDING AUTHOR:

5 East 98th Street, 2nd Floor New York, New York 10029

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Work phone number: 212-241-5681 Cell phone number: 917-971-2843

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Fax number: 212-348-7438

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Katherine A. Connolly, MD

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E-mail: [email protected] ABSTRACT WORD COUNT: 299 MAIN TEXT WORD COUNT: 2,529

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CONDENSATION: Simultaneous use of oxytocin and Foley balloon for labor induction results in a significantly shorter interval to delivery in nulliparas.

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SHORT VERSION OF TITLE: Foley Balloon Induction of Labor in Nulliparas

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ABSTRACT BACKGROUND: With an increasing rate of induction of labor, it is important to choose induction methods that are safe and efficient in achieving a vaginal delivery. The optimal

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method for inducing nulliparous women with an unfavorable cervix is not known.

OBJECTIVE: To determine if induction of labor with simultaneous use of oxytocin and Foley balloon versus sequential use of Foley balloon followed by oxytocin decreases the time to

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delivery in nulliparous women.

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STUDY DESIGN: We conducted a randomized controlled trial of nulliparous women presenting for induction at a single institution from December 2013-March 2015. After decision for induction was made by their primary provider, women with gestational age ≥ 24 weeks with a non-anomalous, singleton fetus in vertex presentation with intact membranes were offered participation. Exclusion criteria included history of prior uterine surgery, unexplained vaginal

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bleeding, latex allergy, or contraindication to vaginal delivery. Participants were randomized to either simultaneous (oxytocin and Foley balloon) or sequential (oxytocin after expulsion of Foley balloon) induction group. The primary outcome was time from induction to delivery. Secondary

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outcomes included mode of delivery, estimated blood loss (EBL), postpartum hemorrhage

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(PPH), chorioamnionitis and composite neonatal outcome. Maternal and neonatal outcomes were collected via chart review. Analyses were done on an intention to treat basis. RESULTS: A total of 166 patients were enrolled; 82 in the simultaneous and 84 in the sequential group. There were no differences in baseline characteristics in the two groups. Patients who received simultaneous oxytocin with insertion of a Foley balloon delivered significantly earlier (15.92h vs. 18.87h, p=0.004) than those in the sequential group. There was no difference in rate of cesarean section, EBL, PPH, chorioamnionitis or composite neonatal outcome.

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CONCLUSION: Simultaneous use of oxytocin and Foley balloon for induction of labor results in a significantly shorter interval to delivery in nulliparas.

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KEYWORDS: Foley balloon, Induction of labor, oxytocin

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INTRODUCTION Induction of labor is becoming an increasingly common practice in obstetrics, now making up approximately 20% of all births[1]. Induction of labor in the setting of an unfavorable

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cervix may lead to longer lengths of stay, increased hospital costs, and/or increased maternal or neonatal morbidities[2, 3]. In order to mitigate these risks, it is important to choose induction methods that are safe and efficient in achieving a vaginal delivery.

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Cervical ripening prior to induction with oxytocin in women with an unfavorable Bishop score increases the likelihood of a vaginal delivery[4, 5]. There are a variety of mechanical and

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pharmacologic methods that have been studied for this purpose. Prostaglandins may be administered vaginally to mimic the natural processes that occur in the cervical tissue during labor. Mechanical ripening agents may also be used to stimulate endogenous prostaglandin production by stretching myometrial cells[6]. Studies comparing these two methods have

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demonstrated similar efficacy and safety, however a lower rate of uterine tachysystole with fetal heart rate changes is seen with mechanical methods[7]. Due to a low risk of adverse outcomes, mechanical dilation with a Foley balloon has come into favor and its safety and efficacy have

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been established[5, 8].

Because cervical ripening with Foley balloon generally does not result in sustained

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contractions, further induction with oxytocin may be considered. There is paucity of literature guiding the timing of initiation of oxytocin. One randomized study compared simultaneous use of oxytocin and Foley balloon to sequential use of Foley balloon followed by oxytocin once the balloon was extruded[9]. There was no difference in the proportion of deliveries that occurred in <24 hours. This study was not powered to detect a difference based on parity or in time to delivery.

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The most effective induction method in terms of decreasing time to delivery in nulliparous women with an unfavorable cervix remains unknown. Maximizing likelihood of successful vaginal delivery in this population is important and potentially has long-term impact

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on maternal morbidity. The aim of this study was to determine whether simultaneous use of Foley balloon inflated to 60cc and oxytocin decreases time to delivery in nulliparous women compared to the sequential use of Foley balloon followed by oxytocin.

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MATERIALS AND METHODS

A randomized clinical trial of nulliparous women presenting for induction of labor at

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Mount Sinai Hospital in New York City from December 2013-March 2015 was conducted to determine whether simultaneous versus sequential use of Foley balloon with oxytocin decreases induction time to delivery.

Nulliparous women ≥24 weeks gestational age (GA) with a live, non-anomalous

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singleton fetus in vertex presentation, with an initial cervical dilation <3 cm and who were admitted for induction of labor for indications determined by their primary provider and in whom cervical ripening with Foley balloon was planned were eligible for enrollment. Patients with

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prior uterine surgery, unexplained vaginal bleeding, latex allergy or any contraindication to

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vaginal delivery were ineligible.

Eligible women were identified by the labor and delivery staff and approached regarding

their interest in hearing about this study. Patients who were interested were then approached by study personnel and counseled on the risks and benefits of participation. Patients were informed that their participation was voluntary and that choosing not to participate in the study would not affect their care.

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After signing informed consent, participants were randomized using previously prepared envelopes. The randomization envelopes were prepared prior to the start of the study using a random number generator from OpenEpi, Version 3. Cards allocating patients to either

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“oxytocin” or “no oxytocin” groups were placed in 170 sealed, opaque, numbered envelopes. After signing informed consent, participants were then given the next envelope.

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After enrollment, each patient had a transcervical Foley balloon placed in a standard, sterile fashion. A 16F 30cc balloon was used in each case and inflated to 60cc with normal

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saline. Proper placement of the Foley balloon was confirmed by digital or ultrasound exam in all patients. The end of the Foley catheter was taped under tension to the patient’s inner thigh. For those patients assigned to the simultaneous group, oxytocin was started within 1 hour of insertion of the Foley balloon and titrated according to the Icahn School of Medicine at Mount

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Sinai institutional protocol. Oxytocin infusion is started at 2 milliunits/minute. This dose is doubled every 30 minutes to a maximum dose of 16 milliunits/minute (2-4-8-16) and then may be increased by 2 milliunits/minute every 30 minutes to a maximum dose of 30

receiving oxytocin.

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milliunits/minute. Fetal heart rate and contraction patterns are monitored continuously in patients

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For patients assigned to the sequential group, oxytocin was started within 1 hour of

spontaneous expulsion of the balloon using the above institutional protocol. If spontaneous expulsion did not occur, the Foley balloon was removed after 12 hours of cervical ripening. For all patients, the remainder of the patient’s labor was managed by the primary provider in accordance with standard obstetric practice.

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Sample size was determined based on time from induction to delivery. A calculation with an 80% power (alpha 0.05) was performed, which determined that 55 patients in each arm were needed to detect a 20% difference in time to delivery. Additional patients were recruited to

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account for study dropout, incomplete charts or inadvertent study crossover. Secondary

outcomes included cesarean delivery rate, rates of chorioamnionitis, estimated blood loss, rates of postpartum hemorrhage and a composite neonatal outcome.

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Both Intention-to-treat (ITT) and Per Protocol (PP) analyses were performed; however since they were in agreement, only results from the ITT analysis are presented. The mean and

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standard deviation or median and range are presented for quantitative variables, and frequency and percentage for qualitative variables, with comparisons between randomization groups made using the Student's t-test or Wilcoxon rank sum test and Chi-square test, respectively. All hypothesis testing was two-sided and conducted at the 5% level of significance. Analyses were

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performed using SAS version 9.4.

This study was approved by the Institutional Review Board of the Mount Sinai Hospital

RESULTS

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(GCO# 13-1279) and is registered at clinicaltrials.gov (NCT02098421).

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Of 190 women approached about the study, 166 women were enrolled; 82 in the simultaneous and 84 in the sequential group (Figure 1). The data was analyzed on an intention to treat basis. There were 5 patients who were randomized in this study, though did not meet the inclusion criteria: 1 patient had premature rupture of membranes at the time of admission, 1 patient had a fetus with known fetal cardiac anomaly, 1 patient was >3cm dilated at time of Foley balloon insertion, 1 patient was pregnant with twins, 1 patient had a prior uterine scar from myomectomy. Two patients received the wrong intervention: 1 patient who was randomized to

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the simultaneous group actually had oxytocin started after expulsion of the Foley balloon and 1 patient who was randomized to the sequential group actually had oxytocin started at the time of Foley balloon insertion. All 7 of these patients were included in the data analysis. An “as treated”

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analysis was also performed and the results were not statistically different.

Baseline demographic factors, medical or obstetric conditions and gestational age were similar in both groups (Table 1). Additionally, there were no differences in admission Bishop

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Score.

Patients in the simultaneous group delivered significantly earlier, by almost 3 hours

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compared to patients in the sequential group (15.92h vs. 18.87h, p=0.004) (Table 2). Patients in the simultaneous group delivered faster at all points in time during the induction (Figure 2). When patients with cesarean delivery were removed, there remained a significant difference in hours to delivery between the groups in patients who delivered vaginally (14.75h vs. 17.61h,

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p=0.02).

There was no difference in the rate of cesarean delivery between the groups (46% vs. 38%, p=0.28) (Table 3). There was, however, an increased rate of cesarean sections performed

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due non-reassuring fetal heart rate tracing in the simultaneous group (29% vs. 3%, p=0.004). There was no difference in the either the maximum rate of oxytocin used or the incidence of

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tachysystole between the two groups. The most common indication for cesarean delivery was failed induction of labor, which was similar between the groups. Patients who were delivered via cesarean section were more likely to be over age 35

(65% vs. 37%, p=0.005) (Table 4). There was no significant difference in mode of delivery based on obesity.

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There were no differences in obstetric and neonatal outcomes between the two groups (Table 5). There was no difference in the rate of chorioamnionitis (P=0.16) or postpartum hemorrhage (P=1.00) between the two groups. There were no cases of rupture of the Foley

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balloon during or after insertion. Additionally, there was no difference in composite neonatal outcome, defined as having ≥1 of the following: 5 minute Apgar <5, umbilical artery pH <7.1, NICU admission, necrotizing enterocolitis, or neonatal death (P=0.26).

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COMMENT

The simultaneous use of Foley balloon and oxytocin in nulliparous women led to a

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decrease in time of induction by 2.95 hours compared to sequential use of Foley balloon then oxytocin. This difference remained significant for those patients who delivered vaginally. There was no difference in overall percentage of women who required cesarean sections in these two groups; however non-reassuring fetal heart rate tracing as the indication for cesarean section was

neonatal outcomes.

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more common in the simultaneous group. There were no other differences in maternal or

To our knowledge, this is the first study powered to detect a difference in time to delivery

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for nulliparous patients undergoing induction of labor using a Foley balloon and either simultaneous or sequential oxytocin. Time from induction to delivery may significantly impact

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total hospital length of stay, allocation of hospital resources including labor and delivery staff, patient satisfaction scores and overall cost[2]. This information is of potentially even greater importance to providers caring for nulliparous patients with an unfavorable cervix, who are known to have longer durations of labor[4, 10]. Our finding of a decrease in time to delivery with simultaneous use of oxytocin may also have clinical implications such as decreased time of immobility from epidural or prolonged supine positioning and thereby a potential reduction in

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thromboembolic events, decreased intake of intravenous fluids, and decreased hospital length of stay. Our finding of shortened time to delivery in nulliparous patients who received

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simultaneous Foley balloon and oxytocin challenges the findings of Pettker et al., who found no difference in length of labor in women who received Foley balloon and oxytocin simultaneously versus sequentially[9]. Their population included both multiparous and nulliparous women and

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their power calculation was done for the group overall. It is known that labor curves vary

between nulliparous and multiparous women[11], hence it is important to stratify these two

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populations to determine the optimal method of labor induction in each. For this reason, the aim of our study was to specifically compare labor induction methods in nulliparous women. There are also differences in induction procedure and management between our study and the prior, which may explain the differing conclusions. Specifically, the oxytocin protocol used

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at our institution differs from the one used by Pettker et. al, and may influence time to delivery. Another important variable, which has been analyzed in previous studies, is the degree to which the Foley balloon is inflated[12, 13]. Inflation with 60cc has been shown to decrease time to

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delivery; therefore in our institution we routinely inflate Foley balloons to 60cc. This is in contrast to the 30cc used by Pettker et. al, which may account for our findings of a decreased

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time to delivery of nulliparas. Our study supports the previously published data and we recommend inflation of Foley balloon to 60cc for labor induction in nulliparous women. Pettker et al. additionally found an increased need for analgesia in patients

simultaneously receiving oxytocin and Foley balloon, which was not seen in our population [9]. There was a high overall rate of epidural analgesia, with 98% of all participants requesting this

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for labor analgesia. This finding may be more of a reflection of the patient population or local practices at our institution. Secondary analysis found no difference in the rate of cesarean delivery between Foley

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balloon inductions with simultaneous versus sequential oxytocin administration. Of note, the proportion of cesarean sections performed due to non-reassuring fetal heart rate tracing was larger in the simultaneous group. The indication for cesarean delivery was obtained from review

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of the delivery summary in the electronic medical record. Importantly, the overall cesarean

section rates were not different. Future studies incorporating interpretation of heart rate tracing

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abnormalities are needed in order to further explore this finding. It is important to note that the increase in non-reassuring fetal heart rate pattern was not due to increased rates of tachysystole or increased quantity of oxytocin infused, as these were similar between the two groups. Although this finding was statistically significant, the overall number of cases was small. The

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increased incidence of cesarean deliveries performed due to non-reassuring fetal heart rate tracing is of concern and future studies with larger numbers are needed to determine if this finding is a valid concern.

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Although this study was not powered to detect differences in secondary outcomes, there were no differences in overall neonatal and maternal outcomes between the two groups. The

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overall rate of chorioamnionitis was low and similar to those quoted in previous similar studies[9, 14]. Although prolonged exposure to oxytocin is a known risk factor for peripartum hemorrhage[15, 16], the rate of hemorrhage was similar in both groups. There are several limitations to this study. First, patients and providers were not blinded

to the intervention group. Blinding was not possible, as the providers placed orders for oxytocin and the nurses titrated the medication and increased surveillance for patient’s receiving oxytocin

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according to our institutional protocol. The decision to perform a cesarean section in the context of a non-reassuring fetal heart rate tracing or failed induction may have been influenced by the provider’s knowledge of the length of oxytocin exposure, thereby lowering their threshold to

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move to cesarean delivery.

Another potential limitation of this study is the generalizability of our results. Our

oxytocin protocol for induction of labor may vary from those at other institutions, which may

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limit the application of our results at other facilities. Additionally, our cesarean section rate was higher than seen in prior studies[14, 17, 18]. This may be due to the baseline patient

affect the rate of cesarean delivery.

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characteristics at our tertiary-care center in a metropolitan setting, which may independently

Due to the increasing number of inductions of labor, choosing an effective, efficient and safe method of inducing labor is of utmost importance to healthcare providers. The data from

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this randomized trial suggests that simultaneous use of Foley balloon and oxytocin results in a shorter induction-to-delivery time, without increased risk of adverse maternal or neonatal complications. This decreased induction time has potentially substantial impact on healthcare

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providers, patients themselves, as well as hospitals. In the future, these two methods of labor induction should be studied in populations not addressed in this study, such as multiparas or in

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patients with prior cesarean section or with multiple gestation. Our study provides compelling evidence that the use of oxytocin at the time of insertion of Foley balloon should be considered by providers in nulliparous women undergoing induction of labor.

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ACKNOWLEDGMENTS: None

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Martin, J.A., et al., Births: final data for 2013. Natl Vital Stat Rep, 2015. 64(1): p. 1-65. von Gruenigen, V.E., et al., The financial performance of labor and delivery units. Am J Obstet Gynecol, 2013. 209(1): p. 17-9. Spong, C.Y., et al., Preventing the first cesarean delivery: summary of a joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, and American College of Obstetricians and Gynecologists Workshop. Obstet Gynecol, 2012. 120(5): p. 1181-93. Vrouenraets, F.P., et al., Bishop score and risk of cesarean delivery after induction of labor in nulliparous women. Obstet Gynecol, 2005. 105(4): p. 690-7. Obstetrics, A.C.o.P.B.-.-. ACOG Practice Bulletin No. 107: Induction of labor. Obstet Gynecol, 2009. 114(2 Pt 1): p. 386-97. Sciscione, A.C., Methods of cervical ripening and labor induction: mechanical. Clin Obstet Gynecol, 2014. 57(2): p. 369-76. Jozwiak, M., et al., Mechanical methods for induction of labour. Cochrane Database Syst Rev, 2012. 3: p. CD001233. McMaster, K., L. Sanchez-Ramos, and A.M. Kaunitz, Evaluation of a Transcervical Foley Catheter as a Source of Infection: A Systematic Review and Meta-analysis. Obstet Gynecol, 2015. 126(3): p. 539-51. Pettker, C.M., et al., Transcervical Foley catheter with and without oxytocin for cervical ripening: a randomized controlled trial. Obstet Gynecol, 2008. 111(6): p. 1320-6. Simon, C.E. and W.A. Grobman, When has an induction failed? Obstet Gynecol, 2005. 105(4): p. 705-9. Zhang, J., et al., Contemporary patterns of spontaneous labor with normal neonatal outcomes. Obstet Gynecol, 2010. 116(6): p. 1281-7. Delaney, S., et al., Labor induction with a Foley balloon inflated to 30 mL compared with 60 mL: a randomized controlled trial. Obstet Gynecol, 2010. 115(6): p. 1239-45. Levy, R., et al., A randomized trial comparing a 30-mL and an 80-mL Foley catheter balloon for preinduction cervical ripening. Am J Obstet Gynecol, 2004. 191(5): p. 1632-6. Saccone, G. and V. Berghella, Induction of labor at full term in uncomplicated singleton gestations: a systematic review and metaanalysis of randomized controlled trials. Am J Obstet Gynecol, 2015. 213(5): p. 629-36. Ekin, A., et al., Predictors of severity in primary postpartum hemorrhage. Arch Gynecol Obstet, 2015. 292(6): p. 1247-54. Dahlke, J.D., et al., Prevention and management of postpartum hemorrhage: a comparison of 4 national guidelines. Am J Obstet Gynecol, 2015. 213(1): p. 76 e1-10. Miller, N.R., et al., Elective Induction of Labor Compared With Expectant Management of Nulliparous Women at 39 Weeks of Gestation: A Randomized Controlled Trial. Obstet Gynecol, 2015. Tolcher, M.C., et al., Predicting Cesarean Delivery After Induction of Labor Among Nulliparous Women at Term. Obstet Gynecol, 2015. 126(5): p. 1059-68.

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TABLE 1. Baseline demographic data Sequential

N=82

N=84

Maternal Age (SD)

29.72 (6.47)

28.56 (7.27)

29.13 (6.89)

GA at Delivery

39.57 (1.80)

39.21 (1.84)

39.39 (1.82)

1 [0-6]

1 [0-6]

1 [0-6]

31.84 (6.57)

30.52 (5.29)

31.17 (5.97)

Pre-gestational DM

2 (2%)

0 (0%)

2 (1%)

Gestational DM

8 (10%)

6 (7%)

14 (8%)

Chronic HTN

6 (7%)

4 (5%)

10 (6%)

13 (16%)

10 (12%)

23 (14%)

19 (22.62%)

22 (27.5%)

41 (25%)

27 (32.14%)

21 (26.25%)

48 (29.27%)

4 (4.76%)

4 (5%)

8 (4.88%)

8 (9.52%)

5 (6.25%)

13 (7.93%)

Non-reassuring fetal status

1 (1.19%)

5 (6.25%)

6 (3.66%)

IUGR

2 (2.38%)

6 (7.5%)

8 (4.88%0

Elective

3 (3.57%)

4 (55)

7 (4.27%)

ICP

8 (9.52%)

1 (1.25%)

9 (5.49%)

AMA

5 (5.95%)

6 (7.5%)

11 (6.71%)

PROM

1 (1.19%)

0 (0%)

1 (0.61%)

DM

3 (3.57%)

5 (6.25%)

8 (4.88%)

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BMI

Asthma Indication for Induction

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Late Term Gestational HTN

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Oligohydramnios

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Pre-eclampsia

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Admission Bishop Scorea

Overall

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Simultaneous

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Other

3 (3.57%)

1 (1.25%)

4 (2.44%)

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Abbreviations: AMA, advanced maternal age; BMI, Body Mass Index; DM, Diabetes Mellitus; GA, gestational age; HTN, hypertension; IUGR, intrauterine growth restriction; ICP, intrahepatic cholestasis of pregnancy; PROM, premature rupture of membranes; SD, Standard deviation a median [min-max] shown

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TABLE 2. Time to delivery

Hours to vaginal delivery

Sequential

N=82

N=84

15.92 ± 0.73

18.87 ± 0.72

N=44

N=52

14.75 ± 0.73

17.61 ± 0.72

a

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Mean ± SE shown *p <0.05

P-value

0.004*

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Hours to deliverya

Simultaneous

0.02*

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TABLE 3. Delivery data Sequential

P-value

N=82 38 (46%)

N=84 32 (38%)

0.28 0.014

Indication for CD 11 (29%)

1 (3%)

Arrest of Dilation

9 (26%)

9 (30%)

Arrest of Descent

1 (3%)

2 (7%)

13 (37%)

16 (53%)

Failed Operative

1 (3%)

delivery

0 (0%)

Other 12 [4-34]

oxytocin Tachysystole

2 (7%)

0.62

7 (9%)

8 (10%)

0.8245

4.37 ± 0.29

4.25 ± 0.29

0.77

81 (98%)

1.00

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Hours Foley in place

0 (0%)

14 [2-30]

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Maximum rate of

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Failed IOL

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NRFHT

Epidural use

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Cesarean delivery

Simultaneous

80 (98%)

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Abbreviations: CD, cesarean delivery; IOL, induction of labor; NRFHT, non-reassuring fetal heart rate tracing

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TABLE 4. Mode of delivery stratified based on age and obesity No C-Section

C-Section

N=96

N=70

P-value

<35

85 (63%)

50 (37%)

>35

11 (35%)

20 (65%)

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0.005*

Age

0.06

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BMI 54 (65%)

29 (35%)

Obese

42 (51%)

41 (49%)

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Non-Obese

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*p <0.05

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TABLE 5. Maternal and neonatal outcome data Simultaneous

Sequential

N=82

N=84

10 (12%)

5 (6%)

EBLa

400 [150-2500]

400 [150-1000]

0.8263

PPH

2 (2%)

3 (4%)

1.0000

16 (20%)

11 (13%)

Scoreb

0.1607

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Composite Neonatal

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Chorioamnionitis

P-value

0.2627

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Abbreviations: EBL, estimated blood loss; PPH, postpartum hemorrhage a median [min-max] b Composite neonatal score is defined as the presence of ≥1 of the following: 5 minute Apgar <5, umbilical artery pH <7.1, NICU admission, necrotizing enterocolitis, or neonatal death

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FIGURE LEGENDS FIGURE 1: Flowchart of randomization into treatment groups

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FIGURE 2: Kaplan Meier Curve: Probability of delivery at each time point after induction of labor

Enrollment

Approached (n=190)

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Declined to participate (n=24)

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Randomized (n=166)

Allocation

SEQUENTIAL GROUP (n=84): ♦ Received allocated intervention (n=83) 1 person treated off protocol

♦

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♦

SIMULTANEOUS GROUP (n=82): ♦ Received allocated intervention (n=81) 1 person treated off protocol

Follow-Up

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Lost to follow-up (n=0)

Analyzed (n=84)

Lost to follow-up (n=0)

Analysis Analyzed (n=82)

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

Figure 2.