History

Fact Explanation
Prolonged labor Abnormal labor or Dystocia of labor is defined as slow or abnormal progression of labor. This may affect the 1st, 2nd and 3rd stages of labor. Labor progress can be assessed retrospectively by the total length of labor or prospectively by the rate of cervical dilation.[1] The second method is more preferred. Duration of labor depends on the parity. Administration of regional anesthesia impairs uterine contractions due to the inhibitory effect on pelvic nerves. Multiparous women usually show more rapid progress. An active phase lasting more than 12h hence a cervical dilation rate of less than 0.5cm per hour is considered abnormal for the first stage of labor. The second stage is considered delayed if the lasts more the 2.8h in nulliparous women and more than 1h in multiparous women.[2]
Maternal exhaustion Due to prolonged straining.
Fetal distress : Fetal tachycardia and Cardiotocography (CTG) changes. Fetal blood supply is diminished during uterine contractions. The prolonged labor augmented with oxytocin may impair fetal blood flow.
Risk factors/ Aetiology A past history of prolonged labor or obstructed labor may suggest cephalopelvic disproportion. Suspect fetal macrosomia in a patient with diabetes during the antenatal period.[3]
References
  1. SELIN L, WALLIN G, BERG M. Dystocia in labour - risk factors, management and outcome: a retrospective observational study in a Swedish setting. Acta Obstet Gynecol Scand [online] 2008, 87(2):216-21 [viewed 22 August 2014] Available from: doi:10.1080/00016340701837744
  2. EL-SAYED YY. Diagnosis and management of arrest disorders: duration to wait. Semin Perinatol [online] 2012 Oct, 36(5):374-8 [viewed 22 August 2014] Available from: doi:10.1053/j.semperi.2012.04.022
  3. LOWE NK. A review of factors associated with dystocia and cesarean section in nulliparous women. J Midwifery Womens Health [online] 2007 May-Jun, 52(3):216-28 [viewed 22 August 2014] Available from: doi:10.1016/j.jmwh.2007.03.003

Examination

Fact Explanation
General examination : Exhaustion Due to prolonged labor
General examination : Features of dehydration Due to prolonged straining. The lips and mouth may appear dry. The eyes may appear shrunken, capillary refill time is prolonged. In severe cases there may be tachycardia and hypotension. Measure the urine output.
Abdominal examination : Assess uterine contractions Palpate the abdomen during contractions and determine the frequency and the length of contractions. A contraction frequency of less than 2 per 10 minutes with each lasting less than 40s is considered ineffective.
Abdominal examination : Non-engaged head Finding of 3/5 or more of the fetal head palpable above the pelvic brim is supportive for cephalopelvic disproportion.
Abdominal examination : Fetal lie Transverse and oblique lie predisposes to prolonged labor.
Abdominal examination : Malposition The occipitoposterior position is a risk factor for prolonged labor.[1] On abdominal examination there is subumbilical flattening, difficulty in palpating the fetal back and easily palpable fetal limbs. The fetal heart sound are heard more towards the flanks.
Abdominal examination : Fetal tachycardia To detect fetal compromise.
Vaginal examination : Cervical dilatation During the first stage of labor cervical dilatation provides valuable information regarding progression of labor. During the latent phase the rate of dilatation is variable. During the active phase the normal rate in 1cm per hour. The exact value used requires further evaluation.[2]
Vaginal examination : Descent of the presenting part The position of the presenting part is measured in relation to the ischial spines. Progression of the labor can be monitored by assessing the descent of the fetus.
Vaginal examination : Easily felt anterior fontanelle and difficulty in feeling the posterior fontanelle Due to deflexed fetal head. Face presentation may also be detected.
References
  1. MARTINO V, ILICETO N, SIMEONI U. [Occipito-posterior fetal head position, maternal and neonatal outcome]. Minerva Ginecol [online] 2007 Aug, 59(4):459-64 [viewed 22 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/17923836
  2. LETIć M. Inaccuracy in cervical dilatation assessment and the progress of labour monitoring. Med Hypotheses [online] 2003 Feb, 60(2):199-201 [viewed 22 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/12606235

Differential Diagnoses

Fact Explanation
Obstructed labor Obstructed labor is defined as cessation of labor progression despite of adequate uterine contractions. Obstructed labor has a high maternal and fetal mortality rate. Obstructed labor is rare in the developed countries and usually results from neglect. The aetiology is usually mechanical obstruction to delivery from either the passage or the passenger. The commonly encountered causes are cephalopelvic disproportion, malpresentation/ malposition and fetal anomalies such as ascites, conjoint twins, hydrocephalus etc. Uterine masses or ovarian masses may also obstruct the birth pathway. The women may present with severe exhaustion and dehydration. On vaginal examination the vulva appears edematous and the vaginal walls are dry and reddened. On vaginal examination the cervix is fully dilated, marked caput formation and molding are characteristic features. Multiparous women have a higher risk of uterine rupture due to prolonged strong contractions. Commonly encountered maternal complications are infection, obstetric fistulae, genital tract trauma and postpartum hemorrhage. The fetus is usually dead at presentation or may encounter asphyxia and hypoxia related damage. The diagnosis is usually clinical. CTG can be used to assess the fetal condition.[1]
Cephalopelvic disproportion (CPD) Cephalopelvic disproportion occurs when the fetus is unable to pass through the pelvic cavity due to a disproportion in the size of the fetal presenting part or the maternal pelvic cavity. Absolute CPD refers to the total inability progress with vaginal delivery. Small stature of the female is a known risk factor. Anthropoid, android and platypelloid pelvic types predispose to prolonged labor. Maternal bone diseases such as rickets may cause structural changes to the pelvic cavity. Fetal macrosomia due to maternal diabetes, excessive maternal weight gain, pre-pregnancy obesity also predispose to prolonged labor due to CPD.[2] The diagnosis can usually be made by physical examination.
Malpresentation/ Malposition Transverse and oblique lie have no mechanism of labor. Abnormal lie can be diagnosed by abdominal examination. These women require caesarean section. Brow and face presentation identified by vaginal examination also predispose to prolonged labor. Brow presentation does not have a mechanism of labor and presents with prolonged labor. Mento-anterior face presentation usually can be delivered vaginally, while mento-posterior position usually requires emergency caesarean section. Occipitoposterior position is the commonest encountered malposition. The diagnosis can be made by abdominal findings - subumbilical flattening, difficulty in palpating the fetal back, easily palpable fetal limbs and fetal heart sound heard towards the flanks. On vaginal examination the anterior fontanelle is more prominent than the posterior fontanelle. Ultrasonography has being shown to be superior in diagnosis compared to vaginal examination alone.[3] For vaginal delivery to occur a long arc rotation must occur which in turn prolongs the labor.
References
  1. NEILSON J.. Obstructed labour. British Medical Bulletin [online] 2003 December, 67(1):191-204 [viewed 22 August 2014] Available from: doi:10.1093/bmb/ldg018
  2. MAHARAJ D. Assessing cephalopelvic disproportion: back to the basics. Obstet Gynecol Surv [online] 2010 Jun, 65(6):387-95 [viewed 22 August 2014] Available from: doi:10.1097/OGX.0b013e3181ecdf0c
  3. MALVASI A., TINELLI A., BARBERA A., EGGEBø T.M., MYNBAEV O.A., BOCHICCHIO M., PACELLA E., DI RENZO G.C.. Occiput posterior position diagnosis: vaginal examination or intrapartum sonography? A clinical review. J Matern Fetal Neonatal Med [online] 2014 March, 27(5):520-526 [viewed 22 August 2014] Available from: doi:10.3109/14767058.2013.825598

Investigations - for Diagnosis

Fact Explanation
The diagnosis is clinical Prolonged labor is diagnosed by studying labor management documents. The partogram which has being advocated since 1994 by the WHO has significantly improved the diagnosis and management of labor dystocia.[1] Cervical dilatation and fetal descent are mapped in the partogram. Progression towards the alert or action line indicates the need for interventions.[2] Poor uterine contraction, malpresentation, malposition and cephalopelvic disproportion can be identified by physical examination.
Cardiotocography Cardiotocography provides valuable information regarding uterine contractions and fetal heart rate. The uterine contraction frequency, duration and basal tone of the myocardium can be assessed. Fetal tachycardia and late decelerations suggest fetal distress.
Fetal scalp blood sampling To identify fetal acidosis due to reduced blood supply
References
  1. JAVED I, BHUTTA S, SHOAIB T. Role of partogram in preventing prolonged labour. J Pak Med Assoc [online] 2007 Aug, 57(8):408-11 [viewed 22 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/17902525
  2. LAVENDER T, ALFIREVIC Z, WALKINSHAW S. Effect of different partogram action lines on birth outcomes: a randomized controlled trial. Obstet Gynecol [online] 2006 Aug, 108(2):295-302 [viewed 22 August 2014] Available from: doi:10.1097/01.AOG.0000226862.78768.5c

Investigations - Fitness for Management

Fact Explanation
Serum electrolytes To identify electrolyte imbalances.
Arterial blood gas analysis Lactic acidosis may develop in prolonged labor.
References

Management - General Measures

Fact Explanation
Patient reassurance The patient may be anxious and worried. Provide adequate information regarding the condition and reassure her with regular updates about progression of labor. Explain the treatment options/interventions about to be undertaken.
Correct dehydration and electrolyte imbalances Maintain adequate hydration with oral fluids. Intravenous fluids may be required in certain women. Certain studies have shown that increased intravenous hydration during labor may even reduce the risk of labor dystocia and the need for augmentation with oxytocin.[1]
Nutrition A simple snack or fluids can be provided to avoid hypoglycaemia. IV Dextrose may be needed in severe patients.
Pain relief Provide adequate pain relief. Epidural anesthesia is the optimum pain relief method. There is minimum effect on the duration of the first stage of labor but may affect the second stage. Epidural anesthesia does not increase the risk of caesarean section and rarely predisposes to labor dystocia.[2] If not available intramuscular opioids can be used.
Antibiotic therapy The risk of infections is increased in prolonged labor. Antibiotics can be used for prophylaxis and treatment of infections.
Be prepared for emergency operative delivery Inform the theater, obstetric team, anesthetist and neonatologist in patients who fail to respond to medical therapy. Equipment required for resuscitation, delivery forceps, neonatal resuscitator should be quickly available.
References
  1. GARITE TJ, WEEKS J, PETERS-PHAIR K, PATTILLO C, BREWSTER WR. A randomized controlled trial of the effect of increased intravenous hydration on the course of labor in nulliparous women. Am J Obstet Gynecol [online] 2000 Dec, 183(6):1544-8 [viewed 22 August 2014] Available from: doi:10.1067/mob.2000.107884
  2. ZHANG J, YANCEY MK, KLEBANOFF MA, SCHWARZ J, SCHWEITZER D. Does epidural analgesia prolong labor and increase risk of cesarean delivery? A natural experiment. Am J Obstet Gynecol [online] 2001 Jul, 185(1):128-34 [viewed 22 August 2014] Available from: doi:10.1067/mob.2001.113874

Management - Specific Treatments

Fact Explanation
Use of partography in all pregnancies The partogram should be maintained with continuous monitoring of maternal, fetal and labor parameters. The alert line is marked to indicate the expected progression of cervical dilatation. The action line is marked with a 4 hour difference. Progression beyond the action line indicates the need for operative intervention.
Caesarean section Gross cephalopelvic disproportion, malpresentation and fetal distress requires termination of pregnancy by caesarean section. Avoid augmentation of labor in these circumstances.[1]
Augmentation of labor Artificial rupture of membranes should be carried out if the membranes are still intact. Oxytocin infusion can be started if ARM alone fails to expedite the labor progress. Gradually titrate the oxytocin infusion to achieve 3 or 4 good uterine contractions per 10 minutes. Augmentation of labor in multiparous women should be carried out with caution due to the risk of uterine hyperstimulation and rupture. Consider caesarean section in patients who fail to respond to adequate augmentation.[2]
Management of postpartum hemorrhage Prolonged labor increases the risk of uterine atony due to exhaustion of the myocardium due to prolonged contractions. Genitial tract trauma is also commonly encountered.[3] The third stage of labor should be actively managed with fundal massage, controlled cord traction and utero-tonics. Oxytocin or ergometrine can should be administered after delivery of the fetal anterior shoulder. An oxytocin infusion can be used to further prevent bleeding. Monitor the patient during the first 24h for bleeding.
Neonatal care The risks to the newborn are hypoxia, acidosis, asphyxia, infections and stillbirth.[4] An experienced pediatrician should be present at the time of the delivery. Resuscitate the newborn if required and monitor during the first 24-48h.
References
  1. MAALøE N, SORENSEN BL, ONESMO R, SECHER NJ, BYGBJERG IC. Prolonged labour as indication for emergency caesarean section: a quality assurance analysis by criterion-based audit at two Tanzanian rural hospitals. [online] December, 119(5):605-613 [viewed 22 August 2014] Available from: doi:10.1111/j.1471-0528.2012.03284.x
  2. SELIN L, WALLIN G, BERG M. Dystocia in labour - risk factors, management and outcome: a retrospective observational study in a Swedish setting. Acta Obstet Gynecol Scand [online] 2008, 87(2):216-21 [viewed 22 August 2014] Available from: doi:10.1080/00016340701837744
  3. LU MC, MUTHENGI E, WAKEEL F, FRIDMAN M, KORST LM, GREGORY KD. Prolonged second stage of labor and postpartum hemorrhage. J Matern Fetal Neonatal Med [online] 2009 Mar, 22(3):227-32 [viewed 22 August 2014] Available from: doi:10.1080/14767050802676709
  4. MYLES TD, SANTOLAYA J. Maternal and neonatal outcomes in patients with a prolonged second stage of labor. Obstet Gynecol [online] 2003 Jul, 102(1):52-8 [viewed 22 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/12850607