INTRODUCTION — This topic will present a paradigm for intrapartum management of the second stage of labor (ie, time from recognition of complete cervical dilation on vaginal examination to fetal expulsion). Our approach is based upon findings from randomized trials when available, as well as our clinical experience, data from observational studies, and expert opinion. As in the first stage, creating a positive childbirth experience is one of the goals of care in the second stage.
Intrapartum care in the first and third stage of normal labor is discussed separately:
Detailed discussion of specific subjects related to labor and birth and intrapartum care of complicated labor and birth are also reviewed separately in individual topic reviews on each subject (eg, abnormal progression, preterm labor, cervical ripening and induction, operative vaginal delivery, cesarean birth, malpresentation, analgesia and anesthesia, support, maternal medical/obstetric disorders, episiotomy, multiple gestation, postpartum hemorrhage).
Management of labor and delivery during the coronavirus disease 2019 (COVID-19) pandemic is reviewed separately. (See "COVID-19: Intrapartum and postpartum issues", section on 'Approach to infection control during the pandemic'.)
COURSE — During labor, the fetus in vertex presentation undergoes a series of movements that facilitate passage through the pelvis and soft tissues of the birth canal: engagement of the biparietal diameter at the pelvic inlet; descent into the vagina; flexion of the neck and internal head rotation to clear the pelvic outlet, usually to an occiput anterior position; extension of the neck from upward pressure on the head from maternal soft tissues; head expulsion; restitution of the head to realign with the shoulders; and then further external rotation as the shoulders undergo internal rotation from the oblique to the anteroposterior diameter for birth [1,2]. These movements are necessary to avoid presenting diameters of the nonspherical head that are larger than the diameters of the bony pelvis through which the head must traverse and because the pelvic outlet is at a 90-degree angle to the pelvic inlet.
The course of the second stage is affected by several maternal and fetal factors, including :
●Pelvic size and shape (figure 1). Android pelvic shapes are associated with more occipitoposterior positions during labor. (See "Labor: Overview of normal and abnormal progression", section on 'Fetal and pelvic factors'.)
●Uterine contraction strength and frequency. (See "Labor: Overview of normal and abnormal progression", section on 'Uterine factors'.)
●Maternal position. (See 'Maternal position while pushing and giving birth' below.)
●Maternal expulsive efforts, although active maternal effort is not essential; unconscious patients and those with complete spinal cord injury can give birth without obvious active expulsive efforts.
●Fetal size and position. (See "Labor: Overview of normal and abnormal progression", section on 'Fetal and pelvic factors'.)
●Parity and use of neuraxial anesthesia (table 1).
CONTINUOUS SUPPORT — Continuous labor support, particularly by a doula, has psychological and obstetric benefits, as shown in the table (table 2). These benefits begin in the first stage and continue through the second and third stages of labor.
In the second stage, pushing (contraction of voluntary striated muscles of the diaphragm and abdominal wall) is partly a response to stimulation of the pelvic floor by the descending presenting part and partly a voluntary effort that is self-initiated and/or directed by a birth attendant, such as a doula or other labor support person . (See "Continuous labor support by a doula" and 'Pushing' below.)
MONITORING FETAL HEART RATE AND DESCENT
●The frequency of fetal heart rate (FHR) monitoring is increased in the second stage. At a minimum, the American College of Obstetricians and Gynecologists (ACOG) suggests review of FHR tracings in low-risk pregnancies every 15 minutes in the second stage . For higher-risk pregnancies, ACOG suggests reviewing the tracing every five minutes in the second stage. Closer assessment and intervention may be indicated when abnormalities are identified. (See "Labor and delivery: Management of the normal first stage", section on 'Fetal heart rate monitoring' and "Intrapartum fetal heart rate monitoring: Overview" and "Intrapartum category I, II, and III fetal heart rate tracings: Management".)
●Vaginal examinations are often performed at one- to two-hour intervals to evaluate descent and head position unless the fetal head is visible at the introitus.
Inadequate descent over time associated with hypocontractile uterine activity is an indication for oxytocin augmentation. (See "Labor: Diagnosis and management of a prolonged second stage", section on 'Patients with inadequate descent and/or rotation'.)
Inadequate descent over time of a fetus in occiput posterior (OP) or transverse position may be an indication for rotation. (See 'Malposition' below.)
PERINEAL PREPARATION TO REDUCE TEARS — Application of warm compresses and perineal massage have been proposed as means of softening and stretching the perineum to reduce perineal trauma during birth. Warm compresses also may provide patients a positive sensory experience during childbirth without anesthesia. Although not harmful and supported by some meta-analyses [4-6], in our practice, we do not advise patients to perform antenatal perineal massage nor do we perform second-stage perineal massage or apply warm compresses to the perineum in the second stage. Trials suggesting a benefit have major methodologic limitations due to lack of blinding, differences in the provision of usual care, and inability to address the importance of other factors related to perineal injury.
If used, warm compresses can be made from clean wash cloths or perineal pads immersed in warm tap water (up to 110° Fahrenheit [43° Celsius]) and wrung to release excess water [7,8]. They are held against the mother's perineum during and between pushes, and changed as needed to maintain warmth and cleanliness. Perineal massage is performed during and between pushes with two fingers of the lubricated gloved hand moving from side to side just inside the patient's vagina and exerting mild, downward pressure on the perineum. A water-soluble lubricant should be used.
Data from meta-analyses of randomized trials show:
●In laboring patients ≥36 weeks, applying warm compresses during the second stage of labor :
•Reduced occurrence of third- and fourth-degree tears compared with hands off or no warm compresses (2.1 versus 4.5 percent; risk ratio [RR] 0.46, 95% CI 0.27-0.79; four trials, 1799 participants, moderate quality evidence, substantial heterogeneity among trials).
•Reduced third- and fourth-degree tears compared with hands off/usual care (1.4 versus 2.9 percent; RR 0.49, 95% CI 0.25-0.94; five trials, 2477 participants).
•Rates of intact perineum (2.3 to 2.4 percent, moderate quality evidence) and minor trauma (eg, first- and second-degree tears, 1.8 to 3.4 percent, very low-quality evidence) appeared to be similar for the intervention and nonintervention groups.
●In laboring patients ≥36 weeks, compared with no massage, perineal massage applied by a midwife during the second stage (nine trials, 3374 participants) :
•Reduced severe perineal trauma (1.3 versus 2.9 percent; RR 0.49, 95% CI 0.25–0.94)
•Reduced episiotomy use (22.1 versus 33.0 percent; RR 0.56, 95% CI 0.38–0.82)
•Increased the incidence of intact perineum (30.4 versus 26.6 percent; RR 1.40, 95% 1.01–1.93)
●In antepartum patients who performed digital perineal massage for at least the last four weeks of pregnancy, perineal trauma (mainly episiotomies) was reduced but the rates of first- or second-degree perineal tears and third-/fourth-degree perineal trauma were similar in the intervention and no intervention groups .
Although a multicenter trial in Sweden including nearly 4000 patients randomly assigned to two versus one midwife during the second stage reported that having an additional midwife reduced the risk of severe perineal trauma (3.9 versus 5.7 percent, adjusted OR 0.69-0.97), there were substantial limitations to the design . For example, the outcomes were subjective, the outcome assessors were not blinded, the biologic plausibility was unclear as there were no statistically significant differences between groups in perineum-protecting interventions (warm compresses, manual perineal protection, birth position), the actual actions of the second midwife could not be measured, and no cost analysis was performed. Of note, the assisted vaginal delivery rate was lower and the episiotomy rate was higher in the two-midwife group, although the difference was not statistically significant; these factors, especially a higher proportion of mediolateral episiotomies, could account for the results.
Early versus delayed — We generally prefer that patients begin pushing soon after complete cervical dilation is identified (called early or immediate pushing) to minimize the duration of the second stage; however, if the fetal heart rate (FHR) pattern is normal and the station is high, patients may delay pushing (also called laboring down or the passive phase of the second stage) for as much as an hour until the further descent has occurred to reduce the duration of maximal maternal exertion. This decision is based on patient-specific factors, such as whether there is a need to expedite delivery, maternal fatigue, motor blockade from neuraxial anesthesia, and maternal preference. There is no strong evidence that the net benefit of one approach is better than that of the other.
In a meta-analysis of term singleton pregnancies randomly assigned to delayed or immediate pushing (12 trials, 5445 participants) :
●Delayed pushing resulted in less time spent actively pushing (mean difference -27.54 minutes, 95% CI -43.04 to -12.04).
●However, this was at the expense of a longer second stage (mean difference 46.17 minutes, 95% CI 32.63-59.71) and the longer second stage was associated with an increased risk for chorioamnionitis (9.1 versus 6.6 percent, risk ratio [RR] 1.37, 95% CI 1.04-1.81) and low umbilical cord pH, as defined by individual trial authors (2.7 versus 1.3 percent, RR 2.00, 95% CI 1.30-3.07).
●Rates of spontaneous vaginal, assisted vaginal, and cesarean birth were similar for both approaches.
All participants had neuraxial analgesia. The overall quality of evidence was considered low because of inconsistency and indirectness due to the high heterogeneity of the included trials.
In a subsequent trial, the frequency of occult levator ani muscle injury on ultrasound examination up to six months postpartum was similar for nulliparous patients who underwent immediate pushing and those who underwent delayed pushing .
Breathing/pushing technique — In our practice, we advise patients to bear down when they feel the need (ie, spontaneous pushing or physiologic pushing), unless neuraxial anesthesia has inhibited the bearing down sensation. Although a common practice is to tell parturients to pull back their knees, tuck in their chin, take a deep breath, bear down at the start of a contraction, and push for 10 seconds with the goal of three pushes per contraction, there is no strong evidence that coaching individuals in this way has any benefit or harm compared with allowing them to bear down and push according to their own reflex needs in response to the pain of contractions and the pressure felt from descent of the fetal head.
We advise against Valsalva pushing (pushing with a closed glottis) as there is no clinically significant benefit to this technique. It is not harmful, but results in transient maternal cardiovascular effects. (See "Vagal maneuvers", section on 'Valsalva maneuver'.)
●In a meta-analysis of randomized trials of different breathing and pushing techniques (21 trials, 3763 participants), maternal and newborn outcomes were similar for parturients who followed their own instincts about breathing while pushing (ie, spontaneous pushing) versus those who were told to take a deep breath at the beginning of a contraction and hold it as long as possible while bearing down (ie, directed pushing with Valsalva maneuver) . All trials were limited by lack of blinding and by crossover between groups, and the overall quality of evidence was low.
Malposition — Expectant management is appropriate for occiput posterior (OP) and occiput transverse (OT) positions early in the second stage as long as the FHR pattern is reassuring and descent is occurring. Most fetuses who are OP or OT at the beginning of the second stage will rotate spontaneously to occiput anterior, justifying an expectant approach. If descent slows or arrests, manual rotation may be indicated. Timing of rotation and other management issues are reviewed separately. (See "Occiput posterior position" and "Occiput transverse position".)
Duration — The diagnosis of abnormally long second stage is based on the 95th percentile for the duration of the second stage in contemporary patients who have normal vaginal births (table 1),as well as expert consensus and agreed-upon definitions for what is normal and safe. A major focus of efforts to reduce the rate of primary cesarean births performed in the second stage is to allow a longer maximum time in the second stage before considering it prolonged. In the United States, the following guidelines are in use:
●In nulliparous patients, the second stage generally can be considered prolonged:
•After three hours of pushing. However, a longer duration (commonly up to four hours of pushing) may be appropriate for patients with epidural anesthesia or with a fetal malposition if progress is documented and fetal testing reassuring.
●In parous patients, the second stage generally can be considered prolonged:
•After two hours of pushing. However, a longer duration (commonly, up to three hours of pushing) may be appropriate for patients with epidural anesthesia or with a fetal malposition if progress is documented and fetal testing reassuring.
Concerning fetal or maternal status necessitates consideration of operative delivery prior to reaching the described time limits.
The diagnosis and management of a prolonged second stage are reviewed separately. (See "Labor: Diagnosis and management of a prolonged second stage".)
MATERNAL POSITION WHILE PUSHING AND GIVING BIRTH — If no fetal manipulation or complications are anticipated, parturients should push in almost any position that they find comfortable. Upright positions where the pelvis is in a vertical or near vertical plane (eg, patient is semirecumbent [variously defined as head and torso at an angle of >30 to 45 degrees], sitting, kneeling, or squatting [unaided or aided]) have several known and theoretic advantages, such as increasing pelvic dimensions, improving fetal alignment within the birth canal, increasing the capacity for pelvic joint movement, and avoiding risk of aortocaval compression. However, available data do not support a strong recommendation for a particular position, except for avoiding aortocaval compression in supine or nearly supine positions. A left or right lateral position avoids this complication and is also acceptable.
When need for fetal manipulation or when optimal surgical exposure is anticipated, however, a semirecumbent position (trunk tilted forwards up to 30 degrees to the horizontal) is advantageous; stirrups are not mandatory .
In meta-analyses of randomized trials:
●In patients without neuraxial anesthesia, compared with supine positions, any upright position resulted in (30 trials, 9015 participants) :
•Reduction in the duration of the second stage by 6.2 minutes (95% CI -9.7 to -2.6)
•Reduction in episiotomy (30.5 versus 40.6 percent; risk ratio [RR] 0.75, 95% CI 0.61-0.92)
•Reduction in forceps- and vacuum-assisted vaginal delivery (9.6 versus 12.8 percent; RR 0.75, 95% CI 0.66-0.86)
•Increased risk for blood loss greater than 500 mL (4.4 versus 6.5 percent; RR 1.48, 95% CI 1.10-1.98)
•Unclear effect on cesarean birth rates (1.8 versus 1.4 percent; RR 1.22, 95% CI 0.81-1.81).
•Unclear effect on third-/fourth-degree lacerations (1.3 versus 0.9 percent; RR 0.72, 95% CI 0.32-1.65)
•Unclear effect on newborn intensive care unit (NICU) admission (2.8 versus 3.6 percent; RR 0.79, 95% CI 0.51-1.21)
However, the overall evidence was of low quality (eg, poorly conducted trials, variations between trials and in how the findings were analyzed).
●In patients with neuraxial anesthesia, there were no clear differences in any of these outcomes between groups (8 trials, 4464 participants) . The overall evidence was of low quality because of differences in trial designs, interventions, and adherence to the allocated intervention, as well as possible selection and attrition bias.
General procedure — The procedure for spontaneous vaginal birth is described below. Forceps- and vacuum-assisted vaginal birth and cesarean birth are reviewed separately. (See "Operative vaginal birth" and "Cesarean birth: Postoperative issues" and "Cesarean birth: Preoperative planning and patient preparation" and "Cesarean birth: Surgical technique".)
The responsibilities of the health care provider are to reduce the risks of maternal perineal trauma and fetal injury during birth and provide initial support of the newborn. There is no consensus regarding the best method for protecting the perineum at birth [7,8,16-23], other than avoiding routine midline episiotomy. Options include guiding fetal expulsion between contractions versus during a contraction, and various methods of using the accoucheur's hands to manage expulsion of the fetal head. The latter may involve no touch ("hands-off") approach or various manual approaches to guide the direction and force of expulsion, such as perineal support, light pressure on the fetal crown, or using fingers placed between the maternal anus and coccyx to actively lift the fetal chin anteriorly (ie, Ritgen's maneuver).
We use the following approach (called the "hands-on" technique) to prevent precipitous expulsion of the newborn, which can lacerate the perineum and anal sphincter [16,23,24].
●The patient is asked to pant or make only small expulsive efforts when the head is fully crowning and delivery is imminent; this prevents the head from being propelled in an uncontrolled manner through the perineum.
●We use one hand to maintain the head in a flexed position and control the speed of crowning and use the other hand to ease the perineum away from the path of the emerging head ("manual perineal protection" ). Some providers support the perineum with a sponge, applying medial pressure. A meta-analysis (five trials, 6816 participants) that evaluated manual perineal support found no clear reduction in obstetric anal sphincter injuries (1.39 versus 1.44 percent; risk ratio [RR] 1.03, 95% CI 0.32-3.36) compared with a "hands-off" approach, although three nonrandomized studies including over 60,000 participants suggested a benefit (2.3 versus 5.0 percent; RR 0.45, 95% CI 0.40-0.50) . A meta-analysis specifically of three trials of Ritgen's maneuver also failed to show a clear protective effect for severe perineal lacerations (RR 0.69, 95% CI 0.10-4.61) . Differences in provider technique and patient factors may explain the wide range of effectiveness in the randomized trials.
The role of various obstetric factors on anal sphincter injury and postpartum function are discussed separately. (See "Obstetric anal sphincter injury (OASIS)".)
●Once the fetal head is out, external rotation (restitution) occurs spontaneously (figure 2).
●If the cord is around the neck (nuchal cord), slipping the cord over the head usually successfully frees the fetus from the tether. If a single nuchal cord is not reducible, we doubly clamp and transect it. Other options for a cord that is difficult to reduce but not tight include slipping it over the shoulders and delivering the body through the loop or delivering the body without reducing the cord (somersault maneuver). It is important to avoid avulsing or tearing the cord while attempting to effect delivery. (See "Nuchal cord".)
●Mucus is gently wiped from the newborn's nose and mouth. In a randomized equivalency trial, wiping the face, mouth, and nose with a towel was equivalent to suction with a bulb syringe . The trial's primary endpoint was mean respiratory rate within the first 24 hours after birth; neonates who were nonvigorous or born with meconium-stained amniotic fluid were excluded. Routine nasopharyngeal suctioning should be avoided. (See 'Nasopharyngeal suctioning' below.)
●After oro-nasopharyngeal care, a hand is placed on each side of the head and the anterior shoulder is delivered with the next contraction, using gentle downward traction toward the mother's sacrum in concert with maternal expulsive efforts. In this way, the anterior shoulder is guided under the symphysis pubis. The posterior shoulder is then delivered by upward traction. These movements should be performed with as little downward or upward force as possible to avoid perineal injury and/or traction injuries to the brachial plexus. The birth is then completed, either spontaneously or with a gentle maternal push.
Cord severance, collection of cord blood, delivery of the placenta, and care of the newborn are discussed separately. (See "Labor and delivery: Management of the normal third stage after vaginal birth", section on 'Cord severance' and "Labor and delivery: Management of the normal third stage after vaginal birth", section on 'Cord blood'.)
Interventions to use selectively or avoid
Water birth — We agree with medical society guidelines discouraging water immersion in the second stage and water birth because of the small but clear risk of potential harm to the newborn in the setting of unproven benefit ; however, water immersion is an acceptable method of labor analgesia in the first stage. (See "Nonpharmacologic approaches to management of labor pain", section on 'Water immersion'.)
In a meta-analysis of randomized trials, water immersion during the second stage did not result in clear benefits or harms in any maternal or neonatal outcome, but evidence was limited and low quality . A systematic review of case reports of poor neonatal outcomes with water immersion found 47 such cases, which included a pattern of cases of Pseudomonas and Legionella infection, sporadic cases of other infections, unexplained neonatal hyponatremia, cord avulsion, and water aspiration . Drowning with death has also been reported .
Episiotomy — The decision to perform an episiotomy should be made on a case-by-case (restricted) basis because routine episiotomy is associated with higher rates of severe perineal trauma and wound complications compared with restricted use. Selection of patients for episiotomy is heavily dependent on the judgment of the clinician regarding the clinical scenario at the time of birth. If performed, mediolateral episiotomy is preferred because the risk of anal sphincter laceration (ie, third- or fourth-degree obstetric injury) is less than with median episiotomy. The evidence for these recommendations is discussed separately. (See "Approach to episiotomy" and "Repair of perineal and other lacerations associated with childbirth".)
Manual fundal pressure — Manual fundal pressure refers to fundal pressure directed towards the birth canal concomitantly with uterine contractions and maternal expulsive efforts to expedite birth. It is not recommended because of unproven maternal or newborn benefit and the potential for harm .
●In a meta-analysis of 10 randomized trials with a total of nearly 5000 singleton cephalic gestations at ≥35 weeks, use of fundal pressure to shorten the second stage for any reason resulted in a 20-minute reduction in the duration of the second stage (mean difference [MD] 20.33 min, 95% CI -28.55 to -12.11) . However, this did not translate into significant differences in clinical maternal and newborn outcomes, such as the rate of vaginal birth (RR 1.00, 95% CI 0.98-1.02), one and five minute Apgar scores, neonatal trauma (RR 0.33, 95% CI 0.01-7.90), vaginal/perineal laceration (RR 0.83, 95% CI 0.57-1.22), cervical laceration (RR 1.30, 95% CI 0.21-8.02), episiotomy (RR 1.08, 95% CI 0.96-1.21), cesarean birth rate (RR 0.72, 95% CI 0.34-1.51), operative vaginal birth (RR 0.79, 95% CI 0.55-1.13) and neonatal intensive care admission (RR 0.33, 95% CI 0.01-7.90). Of potential concern, patients receiving fundal pressure had a lower umbilical cord arterial pH (MD -0.03, 95% CI -0.04 to -0.01) and a nonstatistically significant higher incidence of Apgar scores < 7 at 5 min (4.9 versus 0.7 percent, RR 3.48, 95% CI 0.57-21.32). The quality of these findings is limited by unclear or high risk of bias (eg, lack of blinding) and heterogeneity in the trials (eg, outcomes measured, indication for fundal pressure).
●In a meta-analysis comparing routine application of fundal pressure with no fundal pressure (5 trials, 3057 participants), the intervention did not result in a statistically significant improvement in outcome, including spontaneous vaginal birth rate within a specified period of time (41 versus 39 percent) and reduction in duration of the second stage (mean duration 17.4 versus 16.6 minutes) . The risk for perineal damage was higher in patients who received manual fundal pressure (RR 6.42, 95% CI 0.79-52.37; one trial, 209 participants). However, the trials were small and of low and very low quality.
●In a prospective study including over 8000 pregnancies, approximately one in four parturients received fundal pressure based on the judgment of their clinician, and although fundal pressure was associated with a statistically significant reduction in the duration of the second stage among primiparas (21.6 versus 24.3 minutes), it was also associated with an increased risk of severe perineal laceration in the overall cohort (10.9 versus 7.2 percent) and a trend toward more uterine ruptures (1.5 versus 0.6 percent) . The indications for fundal pressure were failure to progress (44.7 percent), fetal distress (29.3 percent), maternal exhaustion (14.3 percent), and maternal medical condition (11.7 percent).
Expectant management and forceps- or vacuum-assisted birth are good alternatives to fundal pressure; the choice depends on the urgency of the need for fetal expulsion.
A limitation of all studies of fundal pressure is that there is no way to accurately measure the amount of pressure applied. Providers use different techniques and apply different amounts of pressure, which may depend in part on patient characteristics (eg, abdominal obesity).
Fundal pressure is contraindicated in patients with shoulder dystocia as it is ineffective and worsens the impaction. McRoberts maneuver with suprapubic pressure to release the impacted shoulder is the preferred approach. (See "Shoulder dystocia: Intrapartum diagnosis, management, and outcome", section on 'Our approach to management'.)
●Normal newborns – In healthy term newborns, the evidence does not support a benefit of oro-nasopharyngeal suctioning by a bulb or catheter [37-41]. Furthermore, in some studies, suctioning slightly reduced neonatal heart rate and oxygen saturation in the first few minutes of life [37,40,41].
●Meconium-stained newborns – The American Heart Association, the American Academy of Pediatrics, and the American College of Obstetricians and Gynecologists (ACOG) also recommend against routine nasopharyngeal suctioning of meconium-stained newborns [42,43]. Randomized trials have demonstrated that this approach does not decrease meconium aspiration syndrome or improve perinatal outcome. These data are reviewed separately. (See "Meconium aspiration syndrome: Prevention and management", section on 'Obstetrical care'.)
●Newborns with obstructed airways – Suctioning immediately after birth is required for newborns with obvious obstruction to spontaneous breathing due to secretions or who are likely to require positive-pressure ventilation. The mouth is suctioned first and then the nares to decrease the risk for aspiration (newborns are obligate nose breathers). Suctioning of the posterior pharynx should be avoided, as it can stimulate a vagal response, resulting in apnea and/or bradycardia.
Ultrasound — Ultrasound is often used to confirm head position before applying forceps or vacuum for an assisted vaginal birth but is not used routinely during the second stage. A prospective study that evaluated whether sonographic determination of fetal station and position at the initiation of pushing could predict the mode of birth and duration of pushing in 197 nulliparas found that a wider angle of progression (ie, angle between the symphysis pubis and the leading part of the fetal skull) between pushes was predictive of spontaneous vaginal delivery (area under the curve 0.82, 95% CI 0.76-0.87) . The optimal angle of progression and the clinical utility of this information for managing the second stage is unclear as no angle of progression value early in the second stage is sufficiently predictive of dystocia to mandate cesarean birth.
FORCEPS- OR VACUUM-ASSISTED VAGINAL BIRTH — Use of either forceps or vacuum is reasonable when an operative intervention to complete labor is indicated and operative vaginal birth can be safely and readily accomplished; otherwise, cesarean birth is the better option.
The following scenarios are potentially appropriate reasons for assisted vaginal birth:
●Maternal medical indications, such as maternal cardiac disease and a need to avoid pushing in the second stage of labor.
●Prolonged second stage of labor.
●Suspicion of immediate or potential fetal compromise.
●Maternal exhaustion and an inability to push effectively.
However, no indication is absolute, and cesarean birth is also an option in these clinical settings. Assisted vaginal birth is reviewed separately. (See "Operative vaginal birth" and "Procedure for vacuum-assisted vaginal delivery".)
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Labor".)
SUMMARY AND RECOMMENDATIONS
●Definition – The second stage of labor is the time from recognition of complete cervical dilation on vaginal examination to fetal expulsion. (See 'Introduction' above.)
•Fetal heart rate – In low-risk pregnancies, the fetal heart rate (FHR) is monitored at least every 15 minutes in the second stage. For higher-risk pregnancies, the tracing is monitored at least every five minutes. Closer assessment (continuous electronic monitoring) and intervention may be indicated when abnormalities are identified. (See 'Monitoring fetal heart rate and descent' above.)
•Vaginal examinations are performed at one- to two-hour intervals to evaluate descent and head position, unless the fetal head is visible at the introitus. (See 'Monitoring fetal heart rate and descent' above.)
-Inadequate descent over time associated with hypocontractile uterine activity is an indication for oxytocin augmentation. (See "Labor: Diagnosis and management of a prolonged second stage", section on 'Patients with inadequate descent and/or rotation'.)
-Inadequate descent over time of a fetus in occiput posterior (OP) or transverse position may be an indication for rotation. (See 'Malposition' above.)
●Duration of the second stage – The typical duration of the second stage in shown in the table (table 1). In the United States, the following guidelines are used to diagnose a prolonged second stage (see 'Duration' above):
•In nulliparous patients – After three hours of pushing. However, a longer duration (commonly up to four hours of pushing) may be appropriate for patients with epidural anesthesia or with a fetal malposition if progress is documented.
•In parous patients – After two hours of pushing. However, a longer duration (commonly, up to three hours of pushing) may be appropriate for patients with epidural anesthesia or with a fetal malposition if progress is documented.
Management of a prolonged second stage depends on a variety of factors. (See "Labor: Diagnosis and management of a prolonged second stage".)
●Pushing – In our practice, most patients begin to push upon full dilation to shorten the second stage, push in the nonsupine position that they find most comfortable (semirecumbent [variously defined as head and torso at an angle of >30 to 45 degrees], sitting, kneeling, or squatting), and maintain an open glottis.
In pregnancies in which the FHR tracing is normal and station is high, patients may choose to delay pushing for as much as an hour until further descent has occurred to reduce the duration of maximal maternal exertion. This decision is based on patient-specific factors, such as whether there is a need to expedite delivery, maternal fatigue, motor blockade from neuraxial anesthesia, and maternal preference. (See 'Early versus delayed' above and 'Breathing/pushing technique' above and 'Maternal position while pushing and giving birth' above.)
●Protecting the perineum
•Perineal preparation – During the second stage, application of warm compresses and perineal massage may reduce perineal trauma during birth. Although not harmful and supported by some meta-analyses, in our practice, we do not perform second-stage perineal massage or apply warm compresses to the perineum. Trials suggesting a benefit have major methodologic limitations due to lack of blinding, differences in the provision of usual care, and inability to address the importance of other factors related to perineal injury. (See 'Perineal preparation to reduce tears' above.)
•Episiotomy – Routine episiotomy is unnecessary and may be harmful as it is associated with higher rates of severe perineal trauma and wound complications compared with restricted use of episiotomy. (See "Approach to episiotomy".)
•Hands-on technique – At fetal expulsion, we use a "hands-on" technique to prevent precipitous expulsion of the head, which can lacerate the perineum and anal sphincter. (See 'General procedure' above.)
•In most newborns, mucus from the nose and mouth can be gently wiped or suctioned with a bulb. In the absence of respiratory obstruction, nasopharyngeal suctioning, even in newborns with meconium staining, does not improve outcome and can slightly reduce neonatal heart rate and oxygen saturation in the first few minutes of life. (See 'General procedure' above and 'Nasopharyngeal suctioning' above.)