Journal of Midwifery & Women’s Health

www.jmwh.org

Original Review

A Review of Evidence-Based Practices for Management of the Second Stage of Labor

CEU

Mary Lou Kopas, CNM, MN

Management of the second stage of labor often follows tradition-based routines rather than evidence-based practices. This review of second-stage labor care practices discusses risk factors for perineal trauma and prolonged second stage and scrutinizes a variety of care practices including positions, styles of pushing, use of epidural analgesia, and perineal support techniques. Current evidence for management of the second stage of labor supports the practices of delayed pushing, spontaneous (nondirected) pushing, and maternal choice of positions. Perineal compresses, perineal massage with a lubricant, and controlling the rate of fetal extension during crowning may prevent severe perineal trauma at birth. Supine positioning is not recommended. Upright positions and directed pushing can shorten the time from onset of second stage to birth and may be indicated in certain situations, although directed pushing has some associated risks. If the fetus is in the occiput posterior position, immediate pushing is not recommended, and manual rotation can be effective in correcting the malposition. Women should be informed of the potential effects of epidural analgesia on labor progress. Consultation and intervention to expedite birth may be indicated when birth is not imminent after 2 hours of active pushing, or 4 hours complete dilatation, for nulliparous women; or one hour of pushing, or 2 hours complete dilatation, for multiparous women. Each woman should be individually assessed and apprised of the potential risks to her and her fetus of a prolonged second stage of labor, and some women may choose to continue pushing beyond these time limits. c 2014 by the American College of Nurse-Midwives. J Midwifery Womens Health 2014;59:264–276  Keywords: birth, childbirth, review, second stage labor

INTRODUCTION

The second stage of labor is often the most stressful part of the childbearing process for the woman and fetus, and consequently for the provider. Differences of opinion between providers, in combination with a dearth of high-quality evidence, make practice decisions in the second stage particularly challenging. Indeed, the benefits and risks of various interventions to assist women during pushing have been debated for centuries.1–3 This review of the evidence for management of the second stage of labor—including maternal positions, delayed pushing, directed or coached pushing, time limits, and techniques for preventing perineal trauma—is intended to help midwives and other maternity care providers weigh the risks and benefits of these interventions in order to counsel women and provide them with optimal care. MATERNAL POSITIONS Historical Perspectives

A large majority of women (68%) currently give birth either flat on their backs (supine) or in a semisitting (23%) position. Less commonly used birth positions include upright (sitting, standing, or squatting) (4%), side-lying (3%), and hands– knees (1%).4 Historical evidence indicates that women all over the world traditionally gave birth in upright positions, such as standing, squatting, or sitting.2 The lithotomy position for birth began with the advent of forceps in the 18th century and became increasingly common with the popularization of male physician-attended birth.2, 5 By the early 20th century, Address correspondence to Mary Lou Kopas, CNM, MN, Northwest Hospital Midwives Clinic, 10330 Meridian Ave N, Seattle, WA 98133. E-mail: [email protected]

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the lithotomy position was widely used in the United States secondary to the shift from home to hospital birth, the use of twilight sleep, and high rates of forceps use.5 Although assisted vaginal births are now much less common,6 women who have given birth in the last several years report frequent use of supine positioning for labor and birth.4 However, the evidence indicates it is not an ideal position for childbirth. Outcomes Related to Maternal Position

Although high-quality data are lacking, the evidence indicates several potential benefits to upright and lateral positions compared to supine. A retrospective analysis from Australia evaluated the effects of 6 different birth positions (N = 2891) on perineal outcomes including episiotomy, lacerations that required suturing, and intact perineum. The authors found that the lateral birth position had the highest rate of intact perineum (66.6% intact, 28.3% lacerations requiring suturing), whereas squatting was associated with the highest rate of lacerations (41.9% intact perineum, 53.2% lacerations requiring suturing).7 A Cochrane review of 20 randomized controlled trials (RCTs) involving 7280 women compared outcomes of different birth positions for women without epidural analgesia and found that most studies had poor methodological quality and inconsistent interventions.8 A meta-analysis comparing any upright or lateral position to supine or lithotomy position found that nonsupine positions were associated with fewer assisted births (relative risk [RR], 0.78; 95% confidence interval [CI], 0.68-0.90), fewer episiotomies (RR, 0.79; 95% CI, 0.70-0.90), and fewer fetal heart rate (FHR) abnormalities (RR, 0.46; 95% CI, 0.22-0.93), but more second-degree lacerations (RR,1.35; 95% CI,1.201.51) and higher rates of estimated blood loss of more than 500 cc (RR, 1.65; 95% CI, 1.32-2.06).8 They also noted a

c 2014 by the American College of Nurse-Midwives 

✦ Women should choose from a variety of positions in which to push and give birth, but supine and lithotomy positions

should not be used. ✦ Delayed pushing for women with epidural analgesia, especially when the fetal station is high or fetal position is not anterior,

increases the chance of having a spontaneous vaginal birth. ✦ Directing women when and how to push should be considered an intervention to be used only when indicated because

spontaneous pushing is usually safer for the mother and fetus. ✦ Incidence and severity of perineal trauma may be reduced by the use of warm perineal compresses, gentle massage, and

slow crowning of the fetal head either by asking the woman not to push or by use of provider’s hands to slow the extension and birth of the fetal head. ✦ It is unclear whether time limits to duration of second stage of labor improve outcomes, but it is reasonable to consider operative birth when birth is not imminent after a nulliparous woman has been pushing longer than 2 hours or has complete dilatation for more than 4 hours, or after a multiparous woman has been pushing longer than one hour or has complete dilatation for more than 2 hours.

nonsignificant trend toward shorter second-stage labor in upright positions.8 Another Cochrane review of upright versus recumbent birth positions of women with epidural analgesia involving 5 trials and 879 women found no statistically significant outcomes and many methodological inconsistencies.9 Difficulties with some of the RCTs of second stage positions include nonblinding of both providers and participants, women not remaining in assigned positions, and subjectivity of estimated blood loss estimates.8, 9 None of the published studies attempted to differentiate the effects of pushing positions versus positions for birth, which may have different consequences. In summary, there is good evidence that supine positioning should be avoided in second-stage labor. When compared to upright or side-lying positions, supine positions are associated with more FHR abnormalities and fewer spontaneous vaginal births.8 Squatting or sitting may be of benefit when the second stage is prolonged or expeditious birth is indicated, while side-lying or hands–knees positions may help prevent lacerations. It may be that upright is best for pushing, but that lateral or hands–knees are preferable for birthing. DELAYED PUSHING

Delayed pushing, which is also called laboring down or passive descent, is the practice whereby a woman who is completely dilated, but without the urge to push, is allowed to rest and await the urge to push before actively bearing down with contractions.10 Delayed pushing is theorized to promote passive fetal descent and rotation, decrease maternal fatigue, and increase the rate of spontaneous vaginal birth.2 Most midwives (85%) report that delayed pushing is their typical practice for women with epidural analgesia.11 The evidence in support of delayed pushing with epidural analgesia is fairly robust. Several RCTs and 3 meta-analyses, most involving nulliparous women, have compared immediate versus delayed pushing in women with epidural analgesia. Table 1 summarizes the main findings of these studies, all of which involved women at term who had a singleton fetus in vertex presentation and who did not have significant medical complications. The women were randomly assigned to either delayed or immediate pushing once completely Journal of Midwifery & Women’s Health r www.jmwh.org

dilated.12–19 Most of these studies found that delayed pushing resulted in a longer second stage, defined as time from complete dilatation to birth,12–19 but less time spent actively pushing in the group of women who experienced delayed pushing.12–15, 18, 19 The 2 large meta-analyses reported an approximate 10% increase in the number of spontaneous vaginal births (RR, 1.09; 95% CI, 1.03-1.1519 and RR, 1.08; 95% CI, 1.01-1.1518 ) in women who delayed pushing. Additional significant outcome differences included an increase in the rate of unassisted vaginal births,12, 18, 19 decreased perineal trauma,14 fewer FHR decelerations,14 and higher one-minute Apgar scores15 in the group of women assigned to delayed pushing. The Pushing Early or Pushing Late with Epidurals (PEOPLE) study found an increased incidence of maternal fever (temperature ⬎ 38◦ C) in the delayed pushing group but no difference in the incidence of postpartum fever or antibiotic treatment in the mothers—and no differences in antibiotic therapy, blood cultures, or a combined index of morbidity in the newborns.12 Interestingly, the PEOPLE study found the benefit of delayed pushing in terms of reduction in difficult births (defined as cesareans, or instrumentally assisted vaginal births) was greatest if the fetus had been occiput posterior (OP) or occiput transverse (OT) (RR, 0.69; 95% CI, 0.54-0.90 vs RR, 0.90; 95% CI, 0.60-1.19 for occiput anterior [OA] position) or if the station had been above +1 at time of randomization (RR, 0.77; 95% CI, 0.64-0.93 vs RR, 0.82; 95% CI, 0.44-1.51 for station ⬎ +1).12 Most studies found that delayed pushing resulted in little or no difference in adverse maternal and neonatal outcomes. Only one study was found comparing delayed versus immediate pushing in women without epidural analgesia.20 They reported a higher rate of spontaneous vaginal birth (88.9% vs 69.4%; P ⬍ .05), decreased duration of second-stage labor (mean 70.3 [37] min vs 129 [76] min), and decreased duration of pushing in the delayed pushing group (47.3 [31] min vs 123 [74] min), with no differences in maternal or neonatal morbidity.20 However this study was small (N = 62) and did not involve randomization of the intervention but rather allowed the participants to choose between rest or immediate pushing.20 265

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2005

Simpson and James14

2002

Hansen et al13

2000

Fraser et al12

Source

Intervention

Findings Associated with Delayed Pushing Versus Immediate Pushing

Decreased rate of difficult birthsc (RR, 0.79; 95% CI, 0.66-0.95), greater effect for position transverse or posterior position at randomization (RR, 0.69; 95% CI, 0.54-0.90)

medical indication to shorten second stage developed. Control group encouraged to push when

spontaneously pushing, or

medical complications

No difference in Apgar scores, cord pH, or perineal lacerations Decreased duration of pushing: 59 [25] vs 101 [56] minb Fewer instances of fetal oxygen desaturation (⬍ 30%) Fewer variable and prolonged FHR decelerations Fewer perineal lacerations

open glottis pushing ⬍ 6-8 seconds per push vs immediate closed glottis pushing to count of 10 seconds

of labor at term

Increased duration of second stagea : 139 [39] vs 101 [56] minb

h, or urge to push, then instructed in

Rest in left lateral position for up to 2

Lower fatigue scores for nulliparous women

Continued

Fewer variable FHR decelerations per min (nulliparous and parous)

underwent elective induction

RCT, 45 nulliparous women; all

contraction.

Parous: 13 [14] vs 24 [23] minb

Decreased duration of pushing:

directed to Valsalva push with each

introitus when labia spread vs

complete dilatation

Parous: 63 [32] vs 24 [23] minb Nulliparous: 58 [44] vs 77 [41] minb

(parous), or until head seen at

epidural analgesia before

Nulliparous: 171 [57] vs 76 [41 min]b

Increased duration of second stagea :

including Neonatal Morbidity Index scores

No difference in any other maternal or neonatal morbidity measures,

Increased risk of abnormal cord pH (RR, 2.45; 95% CI, 1.35-4.43)

no difference in antibiotic treatment of postpartum fever

immediate pushing. Both groups

120 min (nulliparous) or 60 min

Encouraged to rest and not push for

multiparous women receiving

RCT, 252 nulliparous and

Increased rate of spont vaginal birth (RR, 1.09; 95% CI, 1.0-1.18)

(inspected every 15 min), or if

inadequate pain relief, already

Increased risk of intrapartum T ⬎ 38◦ C (RR, 1.88; 95% CI, 1.31-2.71), but

Decreased duration of pushing: median = 68 vs 110 min

fetal head visualized at perineum

Switzerland; excluded

completely dilated.

Increased duration of second stagea : median duration = 187 vs 123 min

Median delay before onset of pushing: 115 vs 5 min (control group)

for up to 2 h unless irresistible urge,

Instructed to avoid voluntary pushing

12 centers in Canada, US, and

RCT, 1862 nulliparous women at

Participants

Table 1. Summary of RCTs and Meta-Analyses Comparing Delayed Versus Immediate Pushing with Epidural Analgesia

Journal of Midwifery & Women’s Health r www.jmwh.org

267

15

16

19

No difference in maternal fatigue scores or other morbidity measures

complete dilatation

No difference in fatigue scores, lacerations, or number of FHR decelerations

involving 3115 women

assessed as high quality)

meta-analysis of 12 RCTs (9

Systematic review and

involving 2827 women Immediate vs delayed pushing

pushing

Passive descent vs early or immediate

immediate pushing

Meta-analysis of 7 RCTs

analgesia provided in first stage vs

involving 2953 women

Other measures unable to be combined

Decreased duration of pushing (WMD, −22 min; 95% CI, −31 to −13 min)

min[hwy34].)

Increased duration of second stage (WMD, 56.92 min; 95% CI, 42.19-71.64

95% CI, 0.81-0.98)

Decreased risk of instrument-assisted births for nulliparous women (RR, 0.89;

Increased chance of spontaneous vaginal birth (RR, 1.09; 95% CI, 1.03-1.15)

Shorter duration of pushing (MD −0.19 h; 95% CI, −0.27 to −0.12 h)

Decreased risk of instrument-assisted birth (RR, 0.77; 95% CI, 0.71-0.85)

Increased chance of spontaneous birth (RR, 1.08; 95% CI, 1.01-1.15)

Many outcomes could not be combined

No difference in any maternal or fetal outcome measures

No difference in duration of pushing

Increased duration of second stage (WMD, 58.2 min; 95% CI, 21.51-94.84)

0.55-0.87)

Reduction in rotational or midpelvic instrumental births (RR, 0.69; 95% CI,

instructed to push immediately Delayed pushing with effective

Decreased duration of pushing: 39 ± 6.9 vs 79 ± 7.9 minb

uncontrollable urge to push vs

No statistically significant difference in duration of second stagea

Slightly higher one-min Apgar scores: 7.0 [0.5] vs 7.5 [1.3]b

instructed to push within 15 min of Rest for 90 min or until felt

Decreased duration of pushing: 68 [46] vs 95 [57] minb

Increased duration of second stagea : 163 [64] vs 107 [53] minb

Findings Associated with Delayed Pushing Versus Immediate Pushing

to push or birth imminent vs

Rest up to 2 h or until irresistible urge

Intervention

meta-analysis of 9 RCTs

Systematic review and

single site in US

RCT, 44 nulliparous women;

single site in US

RCT, 77 nulliparpous women;

Participants

Abbreviations: CI, 95% confidence interval; FHR, fetal heart rate; h, hours; min, minutes; MD, mean difference; RCTs, randomized controlled trials; RR, relative risk; spont, spontaneous; T, temperature in degrees Celsius; WMD, weighted mean difference. a Duration of second stage defined as time from complete dilatation to birth. b Mean and one standard deviation above and below the mean. c Difficult births defined as those involving second-stage cesarean, use of vacuum or forceps, including rotational forceps, or manual rotation of fetal head by ⬎ 45◦ C.

2012

Tuuli et al

2008

Brancato et al18

2004

Roberts et al17

2010

Kelly et al

2010

Gillesby et al

Source

Table 1. Summary of RCTs and Meta-Analyses Comparing Delayed Versus Immediate Pushing with Epidural Analgesia

How Long to Delay Pushing?

The question of how long women should be allowed to delay pushing has not been answered. No studies compared outcomes with different time limits. Studies to date used limits of one, 1.5, or 2 hours—or until the head was visible at the introitus, the woman had a strong urge to push, or expedited birth was indicated.12–19 Published practice guidelines from the United States and Canada recommend delaying pushing up to one or 2 hours depending on parity and epidural analgesia use.21, 22 The Royal College of Midwives guidelines recommend awaiting the urge to push without stating a time limit.23 The 2012 International Federation of Gynecology and Obstetrics guideline for management of the second stage of labor24 states: Women should not be forced or encouraged to push until they feel an urge to push. . . . In the absence of the urge to push and in the presence of a normal FHR, care providers should wait before encouraging active pushing in primiparous women and women who have had an epidural for up to but not longer than 4 hours [and for] multiparous women [without epidural] for up to but not longer than 1 hour.24(p. 112) It seems reasonable to delay pushing for up to 2 hours after complete dilatation, unless the woman has an urge to push or the fetal head is at the introitus, particularly for women who are using epidural analgesia. Given that prolonged second stage is associated with adverse maternal outcomes such as increased rates of infection, severe lacerations, and postpartum hemorrhage,25, 26 and given the lack of research on longer periods of delay, pushing should be encouraged after one to 2 hours of delayed pushing in the continued absence of fetal descent and the urge to push. Because delayed pushing does increase the duration of second-stage labor, and available studies excluded women with significant medical complications, logic would likewise recommend immediate pushing in situations when expeditious birth is indicated. DIRECTED VERSUS SPONTANEOUS PUSHING

In 1957, the British obstetrician Constance Beynon opined, “Many doctors and midwives still seem to consider it their function to aid and abet and even coerce the mother into forcing the foetus as fast as she can through her birth canal.”3 This style of second stage management, often referred to as directed, coached, closed glottis, Valsalva, or purple pushing, typically involves instructing the laboring woman to take a deep breath, hold it, and bear down hard for a count of 10 seconds, often with a chorus of coaches yelling “Push, push, push!” This prescriptive style of pushing is a persistent cultural phenomenon across the United States, despite decades of discussion in the literature and a lack of evidence to support it.10 In contrast, the physiologic style of second-stage management utilizes spontaneous pushing wherein the provider refrains from giving instruction and instead encourages a woman to push with her body’s instincts when the urge occurs.10, 27, 28 When laboring women are observed without intervention or interruption, spontaneous pushing efforts often start off intermittent and tentative and 268

then gradually build to be more forceful and focused, with several brief pushes (⬍ 6 s) per contraction.29 In a recent survey of certified nurse-midwives (CNMs) and certified midwives (CMs), 82% to 85% report that they allow women to begin pushing only when they feel the urge. A majority of CNMs/CMs (67%) also said that they usually support spontaneous bearing down efforts without giving direction to unmedicated women.11 However, only 35% do so for women with epidural analgesia; and a small but significant portion (16%) reported that they often or almost always direct women without epidural analgesia to make long, sustained pushes with each contraction.11 Research evidence does not support the use of directed pushing. One RCT of 320 unmedicated nulliparous women found that coached closed glottis pushing led to a slightly shorter second stage when compared to a group of women using open glottis or spontaneous pushing (mean duration 46 [41.5] min vs 59 [49] min), but no difference in the incidence of prolonged second-stage labor (defined as duration longer than 2 or 3 h).30 They further found no difference in a variety of outcome measures, including spontaneous vaginal, cesarean, or assisted births; perineal lacerations; Apgar scores; cord pH; or neonatal intensive care unit (NICU) admissions.30 A subset (n = 128) of these women had postpartum pelvic floor function and urodynamic testing performed; researchers found that women who had been randomized to coached (directed) pushing had significantly decreased bladder capacity, decreased first urge to void volume, and more pelvic floor descent at 3 months postpartum.31 Another RCT involved 100 nulliparous women in Turkey, all without access to epidural analgesia, who were randomized to either directed Valsalva pushing or spontaneous pushing.32 Both groups were given information about the assigned pushing style during latent first-stage labor, and both groups began to push when “completely dilated, with intense uterine contractions, and fetal head in OA position and at least +1 station.”32 This study found the directed pushing group, when compared to the spontaneous pushing group, had a longer duration of second-stage labor (mean 50.1 min vs 40.8 min respectively; P ⬍ .05) and a longer duration of active pushing (14.8 vs 9.6 min respectively; P ⬍ .01).32 In addition, the women in the directed pushing group reported less satisfaction with their pushing experience.32 One systematic review of studies comparing directed Valsalva to spontaneous pushing concluded that directed pushing can slightly shorten second-stage labor (mean difference 18 min; 95% CI, 0.46-36.73 min) but may negatively impact urodynamic functioning; whereas no significant difference in other maternal or any neonatal measures was found.33 Another systematic review reported that directed Valsalva pushing may or may not shorten second-stage labor but can lead to significantly higher frequency and severity of perineal lacerations, with no difference in fetal outcomes.34 However, this review included several older studies with poor experimental design.34, 35 Although it may deviate from usual care in many settings, directing a laboring woman when and how to push is an intervention; and as such it should be utilized only in instances when the benefits are judged to outweigh the risks.11, 36 In the absence of clear benefit, and with the distinct Volume 59, No. 3, May/June 2014

possibility of harm, routine directed Valsalva pushing should be avoided. Nonetheless, instructing a woman when to push and encouraging her to push as hard as she can (without prolonged Valsalva) may be of use in certain situations when expeditious birth is indicated and the woman is not yet pushing spontaneously. OCCIPUT POSTERIOR FETUS IN SECOND STAGE

The fetal malposition OP can be challenging to manage during the second stage of labor. Persistent OP can result in a longer second stage and is associated with an increased risk for surgical or instrumental birth.37, 38 Therefore, it is important to accurately diagnose the fetal position and utilize interventions that encourage rotation to OA position. Although it may humble the skilled maternity care provider, evidence indicates that an abdominal ultrasound examination, even when performed by a novice, is more accurate than digital vaginal examination or Leopold’s abdominal examination for determining fetal position.39 A large observational study (N = 1562) using ultrasound examinations found that fetal position commonly changes throughout labor; and most fetuses in OP position eventually rotate spontaneously to OA prior to birth (80% of those OP at 8 cm dilatation were OA by birth) without intervention.37 Although there was no difference in incidence of OP early in labor between women who received epidural analgesia and those who did not, there were significantly more fetuses in OP position close to birth in the women who had epidural analgesia (12.9% vs 3.3%, respectively; P = .002).37 Evidence from the PEOPLE study suggests that delayed pushing when the fetus is OP may increase the chance for a spontaneous vaginal birth without the need for rotational or instrumental intervention.12 Manual rotation of the fetal head from OP to OA has been shown to be a successful intervention that can reduce the incidence of cesarean and vacuum-assisted births.40 Although positioning and movement may help, no RCTs to date have found these interventions to have a significant effect on fetal position. For an excellent review of evidence related to OP position, the reader is referred to a recent review by Simkin.41 DURATION OF SECOND STAGE

Table 2 displays the results of observational studies reporting mean second-stage length and the incidence of prolonged second stage, which is variously defined in the literature.42–50 The length of second stage varies considerably and is affected by parity and epidural analgesia use, as well as other population characteristics and care practices (eg, how often cervical dilatation is assessed and how soon surgical intervention is performed).51–54 The average duration of both the first and second stages of labor have trended up in recent decades, and it is postulated that increased rates of epidural analgesia use and other maternal demographics are at least partly responsible.38, 51, 55 The American College of Obstetrics and Gynecology (ACOG) recommends considering the diagnosis of prolonged second stage in nulliparous woman after 3 hours with regional anesthesia or 2 hours without, and for multiparous women after 2 hours with regional anesthesia or one hour without.51 Risk facJournal of Midwifery & Women’s Health r www.jmwh.org

tors for prolonged second stage include longer first stage of labor,49 nulliparity,25, 26, 45, 48 epidural analgesia use,25, 26, 43–45 body mass index ⬍ 30 kg/m2 ,48 macrosomia,43, 48 increased maternal age or age ⬍ 35 years,43, 48, 49 and OP position.37, 38, 44 For both nulliparous and multiparous women, the second stage of labor is longer and incidence of prolonged second stage is higher for women who use epidural analgesia when compared to women without epidural analgesia.44, 47, 48, 51 Epidural analgesia use has also been found to increase the incidence of assisted vaginal birth.51, 52 Maternal Morbidity and Prolonged Second Stage

Prolonged second stage is, not surprisingly, associated with higher rates of assisted vaginal and cesarean birth,25, 26, 41, 44 and the likelihood of spontaneous vaginal birth has been shown to decrease with each additional hour of duration after the cervix is completely dilated.26, 43 There is a strong association between prolonged second stage and increased maternal morbidity, with the mode of birth being a significant contributing factor. Large retrospective and prospective observational studies report increased rates of chorioamnionitis,25 third- and fourth-degree lacerations,25, 26 uterine atony,25 postpartum hemorrhage,26 intrapartum fever,26 and hysterectomy47 following prolonged second stage or pushing for more than 3 or 4 hours. One of these studies selected duration of pushing rather than time since complete dilatation, collecting data from the PEOPLE study,26 but all others used time since complete dilatation without distinguishing any resting time from time spent pushing. For most of these maternal morbidities, the risk tends to increase with increasing duration of second stage. For example, a retrospective analysis of 4126 nulliparous labors reported third- or fourth-degree laceration rates of 5.1%, 8.4%, 13.8%, 33.6%, 23.5%, and 28.56% for second-stage durations of less than one hour, one to 2 hours, 2 to 3 hours, 3 to 4 hours, 4 to 5 hours, and 5 hours or more, respectively.25 Another study of more than 63,000 births in Nova Scotia reported odds ratios for any maternal morbidity (including infection, hemorrhage, wound complications, or obstetric trauma) of 1.82, 2.51, 2.94, and 3.29 for second stages lasting 2 to 3 hours, 3 to 4 hours, 4 to 5 hours, and 5 hours or more, respectively, when compared to less than or equal to 2 hours.45 Unfortunately, because all studies to date have been retrospective analyses, a causal relationship between prolonged second stage and morbidity is not clear. Most of these outcomes are strongly associated with the mode of birth. That is, spontaneous vaginal birth after a prolonged second stage results in much less morbidity than instrumental or surgical birth after prolonged second stage.25, 26, 43 For example, Rouse et al found that the association between the length of second stage and the incidences of endometritis and blood transfusions were no longer significant after they adjusted for mode of birth.25 Further, an appreciable percentage of women will give birth vaginally even after 3 or 4 hours. In the Rouse et al analysis of 4126 women, 55% of nulliparous women whose second stage lasted 3 hours or more gave birth vaginally,25 and Cheng et al reported that the probability of spontaneous vaginal birth was 15% to 20% for nulliparous women whose second stage lasted more than 4 hours.43 269

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Volume 59, No. 3, May/June 2014

Nulliparous

N = 4126

Duration,

24b (120c ) 6b (66c ) 18b (96c ) 6b (66c )

Nulliparous without epidural P1 with epidural P1 without epidural P2+ with epidural P2+ without epidural

neonatal morbidity at University of California San Francisco 1976-2008

35,681 term, singleton, vertex labors resulting in vaginal birth without

Single site in TX; 84% Hispanic, 61% with epidural

12,523

Single site in TX; ⬎ 80% Hispanic

N = 21,991

Single site in Rome, Italy; all with epidural or CSE

N = 545

parity (nulliparous, parity 1, and parity 2 or more)

18.9 3.0

47 (190 ) 14b (79c ) Multiparous no epidural

16.2 38b (217c )

c

11

Multiparous epidural

b

112b (302c )

36a (18-72)

8

3.2

24

3

Nulliparous without epidural

Nulliparous with epidural

Nulliparous

Nulliparous

70a (26)

36b (168c )

Nulliparous with epidural

N = 58,598

Nulliparous

66b (216c )

Multiparous

Sites throughout Nova Scotia

5 18

35

35

33a (39)

Nulliparous

19 sites across US; sample weighted to achieve representative age, race, and

h ()

103a (80)

19a (21c )

45a (43)

54a (39)

79a (53)

Mean (SD), min

N = 129,517

Multiple sites in US; 94% with epidural

Multiparous no epidural

Multiparous epidural

N = 5119

Single site, UCSF; 44% with epidural

Multiparous

Nulliparous

Single site in Germany, 30% epidural rate, excluded cesarean births

N = 1200

Single site; 56% with epidural

Nulliparous

Multiparous no epidural

stage (87% had no conduction anesthesia)

N = 15,759

Multiparous epidural

Nulliparous without epidural

Nulliparous with epidural

Parity

anesthesia (epidural, 95%, or saddle block, 5%) begun in first or second

Single site; no oxytocin, vaginal births with and without conduction

N = 6991

N and Population Characteristics

h

10.4

6.6

31.1

4

7

15

9

1.4

9.5

11

18

()

h

16.2

2

3.5

3.9

8

()

Abbreviations: CI, confidence interval; CSE, combined spinal epidural; SD, standard deviation; TX, Texas; Mean (SD), min P1, parity 1 (one previous birth); P2+, parity ≥ 2 (at least 2 previous births); UCSF, University of California San Francisco. a Mean duration. b Median duration. c 95th percentile.

2014

Cheng et al50

2013

Nelson et al49

2012

Bleich et al48

2011

Frigo et al47

2010

Zhang et al46

2009

Allen et al45

2009

Rouse et al25

2007

Cheng et al44

2005

Schiessl et al38

2004

Cheng et al43

1989

Kilpatrick and Laros42

Source

Table 2. Observational and Retrospective Reports of Length of Second Stage and Incidence of Prolonged Second Stage for Spontaneous Singleton Labor at Term (≥ 37 weeks’ gestation)

Neonatal Morbidity and Prolonged Second Stage

Although maternal morbidity is clearly increased with prolonged second stage, the evidence of adverse neonatal outcomes with prolonged second stage has not been determined, especially for nulliparous labors. Rouse et al found no association between the length of second stage and the incidence of umbilical cord pH less than 7.0, 5-minute Apgar score lower than 4, intubation, sepsis, or brachial plexus injury. They did find an association between longer duration of the second stage of labor and an increased risk for NICU admission and a composite of any neonatal outcome (primarily due to NICU admission). However, these associations were no longer significant when the comparisons were adjusted for mode of birth.25 Le Ray et al evaluated the outcomes of labor in 1862 nulliparous women who had epidural analgesia and found that, after adjusting for confounding variables such as gestational age, birth weight, and mode of birth, no adverse neonatal outcomes were associated with the duration of pushing.26 Likewise, among 15,759 nulliparous births reported from the University of California San Francisco Medical Center, there was no difference in neonatal outcomes for women whose second stages were longer than 3 hours or longer than 4 hours when compared to women whose second stages were shorter.43 Conversely, 2 published studies have found increased neonatal risks associated with prolonged second stage. A large population-based study of women with a singleton fetus in vertex position who gave birth at term (N = 63,404) in Nova Scotia by Allen et al found that the incidence of 5-minute Apgar scores lower than 7 was higher in newborns of nulliparous women who had a second stage longer than 2 hours (adjusted odds ratio [aOR],1.33; 95% CI, 1.07-1.64) and for newborns of multiparous women who had a second stage longer than one hour (aOR, 1.75; 95% CI, 1.23-2.51) without adjusting for mode of birth.45 The incidence of birth depression, defined as need for mask or intubation for at least 3 minutes, 5-minute Apgar score of 3 or lower, or seizures caused by hypoxic-ischemic encephalopathy, were higher for multiparous women with labors longer than 2 hours (aOR, 1.76; 95% CI, 1.15-2.71). The incidence of minor trauma (aOR, 1.64; 95% CI, 1.26-2.14) and NICU admission (OR, 1.35; 95% CI, 1.17-1.56) were also higher for multiparous women whose second stage was longer than one-hour duration.45 Although this study did not adjust for mode of birth when evaluating neonatal outcomes, they did report that mode of birth was a significant effect modifier for some of these outcomes.45 Another study of only multiparous women adjusted for several confounding variables, including mode of birth, and found higher rates of 5-minute Apgar scores lower than 7 (aOR, 3.63; 95% CI, 1.77-7.43), meconium-stained fluid (aOR, 1.44; 95% CI, 1.07-1.94), NICU admission (aOR, 2.08; 95% CI, 1.15-3.77), and extended neonatal admission (aOR, 1.67; 95% CI, 1.11-2.51) for second stage duration longer than 3 hours compared to second-stage duration less than 2 hours.44 Of note, this database was much smaller (N = 5,158)44 than a similar study from the same site of only nulliparous women (N = 15,759) that found no difference in neonatal outcomes.43 These studies hint at a stronger association between neonatal morbidity and prolonged second stage among mulJournal of Midwifery & Women’s Health r www.jmwh.org

tiparous than nulliparous women. It may be that some pathology can cause both abnormally long labors and abnormal newborn outcomes in the multiparous population. It is also possible that providers are more tolerant of a longer second stage with nonreassuring FHR patterns and are less likely to perform timely interventions for women who have previously given birth vaginally. Shoulder Dystocia and Prolonged Second Stage

A higher incidence of shoulder dystocia has also been associated with prolonged second stage. A study of more than 13,000 women found that prolonged second stage, by the 2003 ACOG definition,51 was associated with an increased incidence of shoulder dystocia (OR, 2.4; 95% CI, 1.7-3.4), although there was no significant association for brachial plexus palsy.53 However, Rouse et al did find a significant association between each added hour of primiparous second stage and brachial plexus injury when adjusted for mode of birth (aOR, 1.78; 95% CI, 1.08-2.78).25 Another single site study of 7,800 women found a statistically significant increase in the frequency of shoulder dystocia only when comparing secondstage durations longer than 4 hours to those less than 2 hours for multiparous women (13.6% vs 0.0%; P ⬍ .001), although no association was found for nulliparous women.54 Time Limits: How Long Is Too Long?

There is disagreement in the literature about setting a time limit to define an abnormal or prolonged second stage.25, 26, 45, 48, 49, 55 Although there is clear evidence of increasing maternal morbidity and some evidence of neonatal morbidity with longer second stages, studies published to date do not tell us whether arbitrary time limits would lead to better outcomes. Therefore, most authors recommend individualized care and counseling.25, 38, 43, 55 A large RCT, with intention-to-treat analysis comparing instrumental vaginal or cesarean birth after a certain time limit to continued expectant management, is needed.55 Until such data are available, and given the evidence that we have, it seems prudent to limit active pushing for multiparous as well as nulliparous women in the context of a lack of progress in descent or nonreassuring fetal heart rate. Professional Association Guidelines

Several authorities recommend time limits for second stage or at least a definition of its prolongation. Table 3 summarizes these recommendations, which range from one to 4 hours depending on parity, epidural analgesia use, duration of active pushing, and progress toward birth.55–57 Some authors differentiate between the passive (or resting) phase and the active (or pushing) phase of the second stage, noting that the duration of pushing is more significantly related to maternal and fetal well-being than the duration of second stage as per its traditional definition of time from complete dilatation to birth.21, 23, 24, 58 Interestingly, ACOG and the Society for Maternal Fetal Medicine recently released a consensus statement on the safe prevention of primary cesarean, which states in part that the maximum time in second stage beyond which 271

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Volume 59, No. 3, May/June 2014

lasted:

birth is imminent

Extending these limits may be appropriate if progress continues and vaginal

maternal and fetal well-being

There should be no arbitrary time limit for the second stage in the presence of

Limit for

analgesia

3 hours without epidural

analgesia

4 hours with epidural

2 hours

second stage (pushing)

3 hours of the start of active

2 hours

anesthesia

≥ 2 hours without regional

anesthesia

⬎ 3 hours with regional

analgesia

⬎ 3 hours without epidural

analgesia

≥ 4 hours with epidural

At least 3 hours of pushing

Nulliparous Women

Limit for

analgesia

2 hours without epidural

analgesia

3 hours with epidural

1 hour

second stage (pushing)

2 hours of the start of active

1 hour

anesthesia

≥ 1 hour without regional

anesthesia

⬎ 2 hours with regional

analgesia

⬎ 2 hours without epidural

analgesia

≥ 3 hours with epidural

At least 2 hours of pushing

Multiparous Women

Abbreviations: ACOG, American College of Obstetricians and Gynecologists; FIGO, International Federation of Gynecology and Obstetrics; NICE, National Institute of Clinical Excellence (United Kingdom); RCM, Royal College of Midwives (United Kingdom) SMFM, Society for Maternal-Fetal Medicine. a Unless specifically stated, time limits refer to time elapsed since complete dilatation noted, without reference to time spent pushing.

(Ottawa Hospital)

2006

Sprague et al21

2007

RCM23

2007

Diagnosis of delay in the active second stage should be made when it has

For most women, birth should be expected to take place within:

NICE58

2012

Should not actively push more than:

Consider diagnosis of a prolonged second stage when:

mandate intervention by operative birth.

If progress is being made, the duration of the second stage alone does not

Second-stage arrest defined as no progress (descent or rotation) for:

being documented.

use of epidural analgesia or with fetal malposition) as long as progress is

Longer durations may be appropriate on an individualized basis (eg, with the

conditions permit, allow for:

Before diagnosing arrest of labor in the second stage, if the maternal and fetal

identified.

beyond which all women should undergo operative birth has not been

A specific absolute maximum length of time spent in the second stage of labor

Definition/Recommendation

FIGO24

2003

ACOG51

2012

Spong et al57

2014

ACOG, SMFM, et al56

Source

Table 3. Recommendations Concerning Time Limits for Second Stage or Pushing Phase of Labora

all women should undergo operative birth has not been determined. They further recommend that the arrest of second stage not be diagnosed until after at least 3 hours of pushing for nulliparous women and until after at least 2 hours of pushing for multiparous women, and that longer durations may be appropriate if progress is being documented.56 Clinical Recommendations

In summary, and after comparing the variety of guidelines published to date, it appears that clinicians in the United States need to be more patient in awaiting the onset of spontaneous pushing but quicker to intervene after 2 hours of strong pushing efforts without progress or birth. Although there are clear risks to the laboring woman, and possibly to the newborn, with a second stage duration longer than 2 or 3 hours (depending on the presence or absence of epidural analgesia and duration of delayed pushing), it is not clear that arbitrary time limits would improve outcomes. It is also not known if the duration of active pushing is more significant than the time elapsed since the dilatation is complete. It seems reasonable to recommend reevaluation and possibly consultation if birth is not imminent when a nulliparous woman has been pushing longer than 2 hours, or is complete for more than 4 hours, and when a multiparous woman has been pushing longer than one hour or is complete for more than 2 hours. HAND TECHNIQUES AND PERINEAL TRAUMA

Various interventions have been proposed to reduce the incidence of perineal trauma, including warm compresses, massage, gentle restraint to slow the egress of the fetal head, maintaining fetal head flexion, no pushing when the perineum is most tense, birth of the head between contractions, and guarding or protecting the perineum with hands.59, 60 Historically, birth attendants were much better at preserving perineal integrity than we are today.61 For instance, DeWees, writing in 1889, reported 51 lacerations among 1,000 births, only 5 of which penetrated to the anal sphincter.62 Delee, in his 1904 textbook, “by proper conduct of labor, most lacerations and nearly all serious ones can be avoided.”63 More recent reports of maternal outcomes in women who have given birth in the United States found that intact perineum rates range from 7% to 69% (ie, laceration rates from 31%93%).59, 61 The incidence of severe lacerations involving the anal sphincter ranges from 0.4% to 15%.64, 65 Overall, the patients of midwives have lower laceration rates than those of physicians,7, 59 and rates are lower for women who give birth at home than for women who give birth in a hospital.59 CNMs/CMs reported intact perineum rates in 2011 of 61.9%, 47.5%, and 46.0% for small-, medium-, and large-sized practices, respectively.66 Laceration rates vary widely among individual providers. Indeed, the individual provider has been found to be a more significant determinant of perineal trauma than fetal size.61 Other risk factors found to be associated with higher incidence and severity of lacerations include nulliparity, larger birth weight, prolonged second stage,64, 65 and very short second-stage duration.64 A number of studies have evaluated interventions to reduce perineal trauma, but the evidence is mixed. The British Journal of Midwifery & Women’s Health r www.jmwh.org

Hands Off or Poised RCT compared the hands-on technique, which involves the provider guarding the perineum and holding flexion of the fetal head, against the hands-off or handspoised style, which involves not touching the fetus or perineum but being ready to apply pressure to slow egress of the fetal head in order to prevent rapid expulsion.67 They found no difference in perineal lacerations, but the women in the hands-on group reported slightly less pain postpartum.67 Another RCT of 1211 women in New Mexico compared 3 techniques: perineal massage with lubricant (“gentle, slow massage, with 2 fingers . . . moving from side to side just inside the patient’s vagina [with] mild, downward pressure toward the rectum . . . applied with steady, lateral strokes, which lasted one second in each direction”), warm cloth compresses (“clean wash cloths made warm by immersion in tap water and squeezed to release excess water . . . held continuously to the mother’s perineum and external genitalia . . . during and between pushes”), or hands off (“no touching of the woman’s perineum during the second stage until crowning of the infant’s head”).68 They found no difference in minor or major perineal trauma.68 A longitudinal study in Norway found a significant reduction in anal sphincter tears (OR, 0.43; 95% CI, 0.38-0.48) 3 years after a well-coordinated educational intervention was implemented at several sites.69 Providers were trained in a hands-on technique that involves one hand pressing down on the fetal head to control and slow the rate of crowning while supporting the perineum with the other hand. Once crowning occurred, the woman was instructed to breathe rapidly, while the attendant pushed the perineal ring under the fetal chin to allow birth of the head.69 A Cochrane review and meta-analysis of 8 RCTs involving more than 11,000 women compared hands on versus hands off, massage versus hands off, and warm compress versus no compress and found no significant difference in incidence of intact perineums with the use of any of these techniques.60 However, both warm compresses and perineal massage reduced the incidence of third- and fourth-degree lacerations compared to hands off or usual care (for warm compresses: RR, 0.48; 95% CI, 0.28-0.84; for massage: RR, 0.52; 95% CI, 0.29-0.94).60 Not surprisingly, hands off (or hands poised) compared to hands on resulted in fewer episiotomies (RR, 0.69; 95% CI, 0.50-0.96), but laceration rates were similar.60 The authors noted small sample sizes and considerable variation of variables among existing studies.60 Spontaneous pushing and side-lying and hands–knees positions are also associated with reduced perineal trauma.7, 68 None of the techniques studied seem to account for the wide variation in rates between sites and providers. It may be that individual practices leading to extremely low laceration rates are part of the art of midwifery that cannot easily be prescribed, and thus their outcomes cannot easily be detected in a RCT design. Although spontaneous laceration rates have risen in recent years,65, 70 it is clear that a large portion of routine perineal trauma, and the associated pain and loss of function,60, 70 may be preventable. Providers are encouraged to be aware of their personal laceration rates and to review rates and hand techniques with colleagues. Until better evidence is available, it appears that best practices are to offer warm compresses or gentle perineal massage with a lubricant 273

per the woman’s comfort and then encourage a slow, gentle crowning of the fetal head over the perineum by instructing the women to blow or make small pushes, or by gently pushing down on the fetal head to control the rate of crowning and prevent a too rapid birth.

Care during the second stage of labor should always be guided by the provider’s professional judgment as informed by the available evidence, with consideration of the individual woman’s preferences and risk factors as well as a thorough and ongoing assessment of her labor pattern and the well-being of her and her fetus.

SUMMARY AND RECOMMENDATIONS

The second stage of labor can be the most stressful phase of labor, but it is also the momentous culmination of the childbearing process when a laboring woman, guided by her providers, actively brings forth a new life. Expectations for care practices used in the second stage of labor should ideally be discussed with women in the prenatal period. Topics of discussion include antenatal perineal massage, the benefits and risks of choosing epidural analgesia (including the possibility of prolonged second stage and persistent OP position), use of delayed pushing if epidural analgesia is chosen, maternal positions, and spontaneous pushing. Interventions in the second stage can potentially disrupt the physiologic process of labor and should be used judiciously. Providers can reduce stress and anxiety by helping laboring women feel safe and supported and by attending to the lighting, sounds, and focus of personnel in the birth room. Women should be encouraged to choose among a variety of positions for pushing, but supine positions should be avoided. Side-lying and hands–knees may the best positions for birth in order to minimize perineal trauma. Whenever possible, laboring women should be allowed the space and time to figure out how to push instinctively. When the fetus is in the OP position, early intervention by manual rotation should be attempted, after first performing a bedside ultrasound examination to confirm the assessment. In deciding when and how to intervene, it is important to consider the duration of pushing, parity, epidural analgesia effects, adequacy of pushing effort, maternal and fetal status, progress in fetal rotation and descent, and women’s preferences. Interventions to expedite birth, with specific instructions and upright positioning, should be undertaken only when indicated, such as when a woman is completely dilated for 2 hours without a spontaneous urge to push, actively pushing for one to 2 hours without descent (after an appropriate time of delayed pushing), or nonreassuring fetal or maternal status when birth is not imminent. For the midwife, consultation with an obstetrician may be appropriate after 2 hours of active pushing without progress for nulliparous women (or 4 hours after complete dilatation with regional analgesia) and after one hour without progress for multiparous women (or 3 hours after complete dilatation with regional analgesia). Even when the second stage of labor is prolonged, an appreciable portion of women can birth vaginally after longer second-stage durations, although there are increased risks for the mother and possibly for her newborn. Each woman should be counseled concerning her options, risks, and chance of vaginal birth, and some will make an informed choice to continue pushing. Warm compresses, perineal massage, and slow crowning of the fetal head may help prevent severe lacerations, and it is possible that reviewing or observing the practice of colleagues with extremely low laceration rates would improve perineal outcomes for some providers. 274

AUTHOR

Mary Lou Kopas, CNM, MN, is in full-scope midwifery practice at the University of Washington Northwest Hospital Midwives Clinic in Seattle, Washington, where she precepts midwifery students from the University of Washington and Seattle University. CONFLICTS OF INTEREST

The author has no conflicts of interest to disclose.

ACKNOWLEDGMENTS

The author wishes to acknowledge Kelly S. McKittrick, CNM, MN, for assistance in review of the literature and Ann Darlington, CNM, MN, for reviewing and editing the article. REFERENCES 1.Dahlen HG, Homer CS, Leap N, Tracy SK. From social to surgical: Historical perspectives on perineal care during labour and birth. Women Birth. 2011;24:105–111. 2.Priddis H, Dahlen H, Schmied V. What are the facilitators, inhibitors, and implications of birth positioning? A review of the literature. Women Birth. 2012;25:100–106 3.Beynon CL. The normal second stage of labor: A plea for reform in its conduct. J Obstet Gynaecol Br Emp. 1957;64:815-820. 4.Declercq ER, Sakala C, Corry MP, Applebaum S, Herrlich A. Listening to Mothers SM III: Pregnancy and Birth. New York, NY: Childbirth Connection; 2013. 5.Dundes L. The evolution of maternal birthing position. Am J Public Health. 1987;77(5):636-641. 6.Gei AF. Prevention of the first cesarean delivery: The role of operative vaginal delivery. Semin Perinatol. 2012;36(5):365-373. 7.Shorten A, Donsante J, Shorten B. Birth position, accoucheur, and perineal outcomes: Informing women about choices for vaginal birth. Birth. 2002;29(1):18-27. 8.Gupta JK, Hofmeyr GJ, Shehmar M. Position in the second stage of labour for women without epidural anaesthesia. Cochrane Database Syst Rev. 2012;5:CD002006. 9.Kemp E, Kingswood CJ, Kibuka M, Thornton JG. Position in the second stage of labour for women with epidural anaesthesia. Cochrane Database Syst Rev. 2013;1:CD008070. 10.Hanson L. Second-stage labor care: Challenges in spontaneous bearing down. J Perinat Neonat Nurs. 2009;23(1):31-39. 11.Osborne K, Hanson L. Directive versus supportive approaches used by midwives when providing care during the second stage of labor. J Midwifery Women’s Health. 2011;57(1):3-11. 12.Fraser WD, Marcoux S, Krauss I, Douglas J, Goulet C, Boulvain M. Multicenter, randomized, controlled trial of delayed pushing for nulliparous women in the second stage of labor with continuous epidural analgesia. The PEOPLE (Pushing Early or Pushing Late with Epidural) Study Group. Am J Obstet Gynecol. 2000;182(5):1165-1172. 13.Hansen SL, Clark SL, Foster JC. Active pushing versus passive fetal descent in the second stage of labor: A randomized controlled trial. Obstet Gynecol. 2002;99(1):29-34. Volume 59, No. 3, May/June 2014

14.Simpson KR, James DC. Effects of immediate versus delayed pushing during second-stage labor on fetal well-being: A randomized clinical trial. Nurs Res. 2005;54(3):149-157. 15.Gillesby E, Burns S, Dempsey A, Kirby S, Mogensen K, Naylor K, Petrella J, Vanicelli R, Whelan B. Comparison of delayed versus immediate pushing during second stage of labor for nulliparous women with epidural anesthesia. J Obstet Gynecol Neonatal Nurs. 2010;39(6): 635-644. 16.Kelly M, Johnson E, Lee V, Massey L, Purser D, Ring K, Sanderson S, Styles J, Wood D. Delayed versus immediate pushing in second stage of labor. MCN Am J Matern Child Nurs. 2010;35(2):81-88. 17.Roberts CL, Torvaldsen S, Cameron CA, Olive E. Delayed versus early pushing in women with epidural analgesia: A systematic review and meta-analysis. BJOG. 2004;111(12):1333-1340. 18.Brancato RM, Church S, Stone PW. A meta-analysis of passive descent versus immediate pushing in nulliparous women with epidural analgesia in the second stage of labor. J Obstet Gynecol Neonatal Nurs. 2008;37(1):4-12. 19.Tuuli MG, Frey HA, Odibo AO, Macones GA, Cahill AG. Immediate compared with delayed pushing in the second stage of labor: A systematic review and meta-analysis. Obstet Gynecol. 2012;120(3):660668. 20.Lai ML, Lin KC, Li HY, Shey KS, Gau ML. Effects of delayed pushing during the second stage of labor on postpartum fatigue and birth outcomes in nulliparous women. J Nurs Res. 2009;17(1):62-72. 21.Sprague AE, Oppenheimer L, McCabe L, Brownlee J, Graham ID, Davies B, Ottawa Hospital. The Ottawa Hospital’s clinical practice guideline for the second stage of labour. J Obstet Gynaecol Can. 2006;28(9):769-779. 22.Association of Women’s Health, Obstetric and Neonatal Nurses. Nursing Care and Management of the Second Stage of Labor, 2nd ed. Washington, DC: Association of Women’s Health, Obstetric and Neonatal Nurses; 2008. 23.Royal College of Midwives. The Second Stage of Labour. Are we Pushing too Hard? London, UK: Royal College of Midwives; 2007. Retrieved from: http://www.rcmnormalbirth.org.uk/research/ literature-review/ 24.FIGO Safe Motherhood and Newborn Health (SMNH) Committee. Management of the second stage of labor. Int J Gynaecol Obstet. 2012;119(2):111-116. 25.Rouse DJ, Weiner SJ, Bloom SL, et al. Second-stage labor duration in nulliparous women: relationship to maternal and perinatal outcomes. Am J Obstet Gynecol. 2009;201(4):357-363. 26.Le Ray C, Audibert F, Goffinet F, Fraser W. When to stop pushing: Effects of duration of second-stage expulsion efforts on maternal and neonatal outcomes in nulliparous women with epidural analgesia. Am J Obstet Gynecol. 2009;201(4):361-367. 27.Roberts J, Hanson L. Best practices in second stage labor care: Maternal bearing down and positioning. J Midwifery Womens Health. 2007;52(3):238-245. 28.Cosner KR, deJong E. Physiologic second stage labor. MCN Am J Matern Child Nurs. 1993;18(1):38-43. 29.Roberts JE, Goldstein SA, Gruener JS, Maggio M, Mendez-Bauer C. A descriptive analysis of involuntary bearing-down efforts during the expulsive phase of labor. J Obstet Gynecol Neonatal Nurs. 1987;16(1):48-55. 30.Bloom SL, Casey BM, Schaffer JI, McIntire D, Leveno KJ. A randomized trial of coached versus uncoached maternal pushing during the second stage of labor. Am J Obstet Gynecol. 2006;194(1):10-13. 31.Schaffer JI, Bloom SL, Casey BM, McIntire DD, Nihira MA, Leveno KJ. A randomized trial of the effects of coached vs uncoached maternal pushing during the second stage of labor on postpartum pelvic floor structure and function. Am J Obstet Gynecol. 2005;192(5):1692-1696. 32.Yildirim G, Beji NK. Effects of pushing techniques in birth on mother and fetus: A randomized study. Birth. 2008;35(1):25-30. 33.Prins M, Boxem J, Lucas C, Hutton E. Effect of spontaneous pushing versus Valsalva pushing in the second stage of labour on mother and fetus: A systematic review of randomised trials. BJOG. 2011;118(6): 662-670. Journal of Midwifery & Women’s Health r www.jmwh.org

34.Bosomworth A, Bettany-Saltikov J. Just take a deep breath: A review to compare the effects of spontaneous versus directed Valsalva pushing in the second stage of labour on maternal and fetal wellbeing. MIDIRS Midwifery Digest. 2006;16(2):157-165. 35.Sampselle CM, Hines S. Spontaneous pushing during birth. Relationship to perineal outcomes. J Nurse Midwifery. 1999;44(1):36-39. 36.Roberts JM, Gonz´alez CB, Sampselle C. Why do supportive birth attendants become directive of maternal bearing-down efforts in second-stage labor? J Midwifery Womens Health. 2007;52(2):134141. 37.Lieberman E, Davidson K, Lee-Parritz A, Shearer E. Changes in fetal position during labor and their association with epidural analgesia. Obstet Gynecol. 2005;105(5 Pt 1):974-982. 38.Schiessl B, Janni W, Jundt K, Rammel G, Peschers U, Kainer F. Obstetrical parameters influencing the duration of the second stage of labor. Eur J Obstet Gynecol Reprod Biol. 2005;118(1):17-20. 39.Ramphul M, Kennelly M, Murphy DJ. Establishing the accuracy and acceptability of abdominal ultrasound to define the foetal head position in the second stage of labour: A validation study. Eur J Obstet Gynecol Reprod Biol. 2012;164(1):35-39. 40.Shaffer BL, Cheng YW, Vargas JE, Laros RK Jr, Caughey AB. Manual rotation of the fetal occiput: Predictors of success and delivery. Am J Obstet Gynecol. 2006;194(5):e7-9. 41.Simkin P. The fetal occiput posterior position: state of the science and a new perspective. Birth. 2010;37(1):61-71. 42.Kilpatrick SJ, Laros RK Jr. Characteristics of normal labor. Obstet Gynecol 1989;74(1):85-87. 43.Cheng YW, Hopkins LM, Caughey AB. How long is too long: Does a prolonged second stage of labor in nulliparous women affect maternal and neonatal outcomes? Am J Obstet Gynecol. 2004;191(3): 933-938. 44.Cheng YW, Hopkins LM, Laros RK Jr, Caughey AB. Duration of the second stage of labor in multiparous women: Maternal and neonatal outcomes. Am J Obstet Gynecol. 2007;196(6):585590. 45.Allen VM, Baskett TF, O’Connell CM, McKeen D, Allen AC. Maternal and perinatal outcomes with increasing duration of the second stage of labor. Obstet Gynecol. 2009;113(6):1248-1258. 46.Zhang J, Landy HJ, Branch DW, et al. Contemporary patterns of spontaneous labor with normal neonatal outcomes. Obstet Gynecol. 2010;116(6):1281-1287. 47.Frigo MG, Larciprete G, Rossi F, et al. Rebuilding the labor curve during neuraxial analgesia. J Obstet Gynaecol Res. 2011;37(11):15321539. 48.Bleich AT, Alexander JM, McIntire DD, Leveno KJ. An analysis of second-stage labor beyond 3 hours in nulliparous women. Am J Perinatol. 2012;29(9):717-722. 49.Nelson DB, McIntire DD, Leveno KJ. Relationship of the length of the first stage of labor to the length of the second stage. Obstet Gynecol. 2013;122(1):27-32. 50.Cheng YW, Shaffer BL, Nicholson JM, Caughey AB. Second stage of labor and epidural use: A larger effect than previously suggested. Obstetrics & Gynecology. 2014;123(3):527-535. 51.American College of Obstetrics and Gynecology Committee on Practice Bulletins-Obstetrics. ACOG Practice Bulletin Number 49, December 2003: Dystocia and augmentation of labor. Obstet Gynecol. 2003;102(6):1445-1454. 52.Anim-Somuah M, Smyth RM, Jones L. Epidural versus nonepidural or no analgesia in labour. Cochrane Database Syst Rev. 2011;(12):CD000331. 53.Ouzounian JG, Korst LM, Miller DA, Lee RH. Brachial plexus palsy and shoulder dystocia: Obstetric risk factors remain elusive. Am J Perinatol. 2013;30(4):303-307. 54.Myles TD, Santolaya J. Maternal and neonatal outcomes in patients with a prolonged second stage of labor. Obstet Gynecol. 2003;102(1):52-85. 55.Caughey AB. Is there an upper time limit for the management of the second stage of labor? Am J Obstet Gynecol. 2009;201(4): 337-338.

275

56.American College of Obstetricians and Gynecologists (the College) and the Society for Maternal-Fetal Medicine, Caughey AB, Cahill AG, Guise JM, Rouse DJ. Safe prevention of the primary cesarean delivery. Am J Obstet Gynecol. 2014;210(3):179-193. 57.Spong CY, Berghella V, Wenstrom KD, Mercer BM, Saade GR. 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):1181-1193. 58.National Institute of Clinical Excellence (NICE) (2007) Intrapartum Care: Care of Healthy Women and Their Babies. London, UK: NICE 59.Albers LL. Reducing genital tract trauma at birth: Launching a clinical trial in midwifery. J Midwifery Womens Health. 2003;48(2): 105-10. 60.Aasheim V, Nilsen AB, Lukasse M, Reinar LM. Perineal techniques during the second stage of labour for reducing perineal trauma. Cochrane Database Syst Rev. 2011;(12):CD006672. 61.Eason E, Labrecque M, Wells G, Feldman P. Preventing perineal trauma during childbirth: A systematic review. Obstet Gynecol. 2000;95(3):464-471. 62.DeWees WB. Relaxation and management of the perineum during parturition. JAMA, 1889;13:804-808. 63.DeLee JB. Obstetrics for Nurses. London, England: W.B Saunders & Company; 1904. 64.Prager M, Andersson KL, Stephansson O, Marchionni M, Marions L. The incidence of obstetric anal sphincter rupture in primiparous women: A comparison between two European delivery settings. Acta Obstet Gynecol Scand. 2008;87(2):209-215.

276

65.Hastings-Tolsma M, Vincent D, Emeis C, Francisco T. Getting through birth in one piece: Protecting the perineum. MCN Am J Matern Child Nurs. 2007;32(3):158-164. 66.American College of Nurse-Midwives. ACNM Benchmarking Project: 2011 Results Summary. Silver Spring, MD: American College of Nurse-Midwives Web publication; 2013. http://www. midwife.org/ACNM/files/ccLibraryFiles/Filename/000000002976/ ACNM%20Benchmarking%20Project%202011%20Final% 20Report%20with%20Table.pdf. Accessed August 18, 2013. 67.McCandlish R, Bowler U, van Asten H, et al. A randomised controlled trial of care of the perineum during second stage of normal labour. Br J Obstet Gynaecol. 1998;105(12):1262-1272. 68.Albers LL, Sedler KD, Bedrick EJ, Teaf D, Peralta P. Midwifery care measures in the second stage of labor and reduction of genital tract trauma at birth: A randomized trial. J Midwifery Womens Health. 2005;50(5):365-372. 69.Hals E, Oian P, Pirhonen T, et al. A multicenter interventional program to reduce the incidence of anal sphincter tears. Obstet Gynecol. 2010;116(4):901-908. 70.Albers LL, Borders N. Minimizing genital tract trauma and related pain following spontaneous vaginal birth. J Midwifery Womens Health. 2007;52(3):246-253.

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Volume 59, No. 3, May/June 2014