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Routine vaginal examinations for assessing progress of labour to improve outcomes for women and babies at term

  1. Soo Downe1,*,
  2. Gillian ML Gyte2,
  3. Hannah G Dahlen3,
  4. Mandisa Singata4

Editorial Group: Cochrane Pregnancy and Childbirth Group

Published Online: 15 JUL 2013

Assessed as up-to-date: 4 JUL 2013

DOI: 10.1002/14651858.CD010088.pub2


How to Cite

Downe S, Gyte GML, Dahlen HG, Singata M. Routine vaginal examinations for assessing progress of labour to improve outcomes for women and babies at term. Cochrane Database of Systematic Reviews 2013, Issue 7. Art. No.: CD010088. DOI: 10.1002/14651858.CD010088.pub2.

Author Information

  1. 1

    University of Central Lancashire, Research in Childbirth and Health (ReaCH) unit, Preston, UK

  2. 2

    The University of Liverpool, Cochrane Pregnancy and Childbirth Group, Department of Women's and Children's Health, Liverpool, UK

  3. 3

    University of Western Sydney, Family and Community Health Research Group, School of Nursing and Midwifery, Penrith Routh DC, NSW, Australia

  4. 4

    University of the Witwatersrand/University of Fort Hare/East London Hospital complex, Effective Care Research Unit, East London, South Africa

*Soo Downe, Research in Childbirth and Health (ReaCH) unit, University of Central Lancashire, Preston, PR1 2HE, UK. sdowne@uclan.ac.uk.

Publication History

  1. Publication Status: New
  2. Published Online: 15 JUL 2013

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Characteristics of included studies [ordered by study ID]
Abukhalil 1996

MethodsRCT


ParticipantsInclusion criteria

  • Nulliparous women in labour with singleton pregnancy.
  • Women were recruited at 32 weeks if they had no fetal or maternal indicators precluding vaginal birth. Women were subsequently withdrawn if any of the exclusion criteria arose.
  • 150 women were randomised but 41 were withdrawn due to development of exclusion criteria, leaving 109 women for whom data were collected.


Exclusion criteria

  • Multiple pregnancy; preterm labour (< 37 weeks); elective CS; induction of labour (though these women seemed to be included); post-term (> 42 weeks); PET/PIH; IUGR; breech; placenta praevia.


InterventionsIntervention: Vaginal examinations every 2 hours.

  • Progress of labour reported on partogram.
  • VEs could be done at other times as indicated, e.g. prior to epidural or pethidine; if full dilation was suspected; application of fetal scalp electrode or taking fetal blood sample.
  • Total number randomised = 75 women.
  • Then 20 (27%) withdrawals for PET/PIH IUGR; preterm labour; breech; post term; placenta praevia.
  • So data on 55 women and infants, except mode of birth for which data were available for all women who were randomised.


Comparison: Vaginal examinations every 4 hours.

  • Progress of labour reported on partogram.
  • VEs could be done at other times as indicated, e.g. prior to epidural or pethidine; if full dilation was suspected; application of fetal scalp electrode or taking fetal blood sample.
  • Total number randomised: n = 75 women.
  • Then 21 (28%) withdrawals for PET/PIH IUGR; preterm labour; breech; post term; placenta praevia.
  • So data on 54 women and infants, except mode of birth for which data were available for all women who were randomised.


OutcomesLength of labour; oxytocin; epidural; spontaneous labour; induced labour; spontaneous vaginal birth; operative vaginal birth; CS.


NotesSetting: Not specifically stated but authors from North Staffordshire Maternity Unit, UK with 6000 births/year.

May 1992 to April 1993

Subgroups:

  1. Timing of VEs: compared 2 vs 4 hourly
  2. Primiparous/multiparous/both
  3. Low- and middle-income countries/high-income country


Additional information

  • ARM not mandatory as long as progress at 1cm/hr. If progress not satisfactory then ARM or oxytocin.
  • Women encouraged to be ambulant in 1st stage and routine CTG not considered essential unless obstetrician indicated.


We are trying to contact the authors to ask about their randomisation process, to see if they have more information on the incidence and treatment of infection, and to ask if they have data on other outcomes.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low risk"... computer derived using random number allocation ..."

Allocation concealment (selection bias)Unclear risk"... group allocated stated on case notes ..." so no information to suggest allocation concealment.

Incomplete outcome data (attrition bias)
All outcomes
High risk150 women were randomised then 27% of women in the 2-hourly arm and 28% of women in the 4-hourly arm were withdrawn because they developed exclusion criteria after randomisation.

Selective reporting (reporting bias)Unclear riskWe did not assess the trial protocol.

Other biasLow riskWe identified no other potential biases.

Blinding of participants and personnel (performance bias)
All outcomes
High riskNo information provided but it was not possible to blind women or personnel.

Blinding of outcome assessment (detection bias)
All outcomes
High riskNo report of any attempt to blind assessors.

Murphy 1986

MethodsRCT


ParticipantsInclusion criteria

  • Women in labour at term with recent rupture of membranes.
  • Total number randomised = 307.


Exclusion criteria

  • None specified.


InterventionsIntervention: Vaginal examination.

  • VE to assess progress in labour.
  • Women examined on entry, 1 hour later then every 2 hours unless more frequent examinations were prompted by slow progress in labour.
  • Woman in dorsal position.
  • Hands scrubbed and sterile surgical gloves worn.
  • Drapes and antiseptics solutions not employed and Hibitane cream used as lubricant.
  • Total number randomised to VE = 154.


Comparison: Rectal examination.

  • Rectal examination to assess progress in labour.
  • Rectal examinations done in the usual way using disposable polythene glove.
  • Drapes and antiseptics solutions not employed and Hibitane cream used as lubricant.
  • Total number randomised to rectal examination = 153.


OutcomesComfort of the pelvic examination (categorical question, 10 cm linear analogue scale, open question); infection, various aspects of labour (CS; vaginal birth; augmentation). The authors also measured 'Admission to NICU' although this was not stated as an outcome in their methods section.


NotesSetting: National Maternity Hospital Dublin from February to April 1984.

Sub groups

  1. Timing of VEs.  Women examined on entry, 1 hour later then every 2 hours unless more frequent examinations were prompted by slow progress in labour.
  2. Primiparous/multiparous/both (data not separated).
  3. Low- and middle-income countries/high-income country only.


We are trying to contact the authors to ask about their randomisation process, to see if they are able to provide their data by parity and to ask if they have on other outcomes.

Of the two perinatal mortalities, one was a stillbirth in the rectal examination group, and the other a neonatal death in the vaginal examination group.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear risk“… randomly allocated … but no information provided on sequence generation.

Allocation concealment (selection bias)Low risk"... serially numbered, sealed, opaque envelopes ..."

Incomplete outcome data (attrition bias)
All outcomes
Low riskOut of 307 women, 3 were 'incorrectly labelled'; 1 in rectal group and 3 in vaginal group missed the questionnaire but still had clinical outcomes assessed.

Selective reporting (reporting bias)Unclear riskWe did not assess the trial protocol.

Other biasLow riskWe identified no other potential biases.

Blinding of participants and personnel (performance bias)
All outcomes
High riskIt was not possible to blind participants or personnel.

Blinding of outcome assessment (detection bias)
All outcomes
High riskWomen's comfort was assessed using by self-administered questionnaires, and women could not be blinded. Similarly, clinicians made the decisions on augmentation, CS and OVB and there was no information to say they were blinded.

 
Characteristics of excluded studies [ordered by study ID]

StudyReason for exclusion

Chanrachakul 2001This study compared use of 'sweeping membranes alongside VEs' versus 'no sweeping membranes and VEs alone' to speed up labour.

Dupuis 2005This study compared the kind of practitioners who undertook VEs, and assessed whether a senior resident was more accurate at assessing position of baby's head than the attending physician. It is not about progress of labour as all women had a fully dilated cervical os when the examination was undertaken.

Foong 2000This study was a trial of membrane sweeping for induction of labour

Fuentes 1995This study compared two different types of gel used to reduce infection when VEs are undertaken.

Peterson 1965This was a quasi-RCT with women allocated to groups alternately.

 
Comparison 1. Vaginal examination versus no intervention

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

1 Length of labour (primary outcome) [minutes]00Mean Difference (IV, Fixed, 95% CI)0.0 [0.0, 0.0]

2 Maternal infection requiring antibiotics (primary outcome)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

3 Neonatal infection requiring antibiotics (primary outcome)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

4 Very positive views of intrapartum care (primary outcome)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

5 Maternal mortality or severe morbidity (composite)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

6 Infant mortality or severe morbidity (composite)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

7 Augmentation of labour00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

8 Epidural for pain relief00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

9 Narcotics for pain relief00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

10 Caesarean section00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

11 Spontaneous vaginal birth00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

12 Operative vaginal birth00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

13 Haemorrhage (> 1000 mL)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

14 Severe perineal damage00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

15 Apgar < 7 at 5 minutes00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

16 Maternal mortality00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

17 Ruptured uterus00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

18 Maternal organ failure00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

19 Maternal admission to intensive care00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

20 Perinatal mortality00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

21 Birth asphyxia00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

22 Neonatal encephalopathy00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

23 Neonatal birth trauma00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

24 Admission to neonatal intensive care unit00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

25 Prolonged hospital stay for mothers00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

26 Prolonged hospital stay for infant00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

27 Re-admission to hospital for mothers00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

28 Re-admission to hospital for infants00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

29 Maternal distress00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

30 Mother willing to accept same intervention in future births00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

31 Maternal incontinence after 6 weeks00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

32 Childhood disability00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

33 Maternal infection with unknown treatment - not prespecified00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

34 Infant infection with unknown treatment - not pre-specified00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

35 Very uncomfortable (not pre-specified)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 
Comparison 2. Vaginal examination versus rectal examination

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

1 Length of labour (primary outcome) [minutes]00Mean Difference (IV, Fixed, 95% CI)0.0 [0.0, 0.0]

2 Maternal infection requiring antibiotics (primary outcome)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 3 Neonatal infection requiring antibiotics (primary outcome)1307Risk Ratio (M-H, Fixed, 95% CI)0.33 [0.01, 8.07]

4 Very positive views of intrapartum care (primary outcome)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

5 Maternal mortality or severe morbidity (composite)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

6 Infant mortality or severe morbidity (composite)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 7 Augmentation of labour1307Risk Ratio (M-H, Fixed, 95% CI)1.03 [0.63, 1.68]

8 Epidural for pain relief00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

9 Narcotics for pain relief00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 10 Caesarean section1307Risk Ratio (M-H, Fixed, 95% CI)0.33 [0.03, 3.15]

 11 Spontaneous vaginal birth1307Risk Ratio (M-H, Fixed, 95% CI)0.98 [0.90, 1.06]

 12 Operative vaginal birth1307Risk Ratio (M-H, Fixed, 95% CI)1.38 [0.70, 2.71]

13 Haemorrhage (> 1000 mL)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

14 Severe perineal damage00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

15 Apgar < 7 at 5 minutes00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

16 Maternal mortality00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

17 Ruptured uterus00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

18 Maternal organ failure00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

19 Maternal admission to intensive care00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 20 Perinatal mortality1307Risk Ratio (M-H, Fixed, 95% CI)0.99 [0.06, 15.74]

21 Birth asphyxia00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

22 Neonatal encephalopathy00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

23 Neonatal birth trauma00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 24 Admission to neonatal intensive care unit1307Risk Ratio (M-H, Fixed, 95% CI)1.32 [0.47, 3.73]

25 Prolonged hospital stay for mothers00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

26 Prolonged hospital stay for infant00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

27 Re-admission to hospital for infants00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

28 Re-admission to hospital for mothers00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

29 Maternal distress00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

30 Mother willing to accept same intervention in future births00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

31 Maternal incontinence after 6 weeks00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

32 Childhood disability00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 33 Maternal infection with unknown treatment (not pre-specified)1307Risk Ratio (M-H, Fixed, 95% CI)0.50 [0.22, 1.13]

 34 Infant infection with unknown treatment (not pre-specified)1307Risk Ratio (M-H, Fixed, 95% CI)0.99 [0.14, 6.96]

 35 Very uncomfortable (not pre-specified)1303Risk Ratio (M-H, Fixed, 95% CI)0.42 [0.25, 0.70]

 
Comparison 6. Vaginal examinations 2 hourly versus 4 hourly

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Length of labour (primary outcome)1109Mean Difference (IV, Fixed, 95% CI)-6.0 [-88.70, 76.70]

2 Maternal infection requiring antibiotics (primary outcome)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

3 Neonatal infection requiring antibiotics (primary outcome)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

4 Very positive views of intrapartum care (primary outcome)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

5 Maternal mortality or severe morbidity (composite)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

6 Infant mortality or severe morbidity (composite)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 7 Augmentation of labour1109Risk Ratio (M-H, Fixed, 95% CI)1.03 [0.64, 1.67]

 8 Epidural for pain relief1109Risk Ratio (M-H, Fixed, 95% CI)0.77 [0.39, 1.55]

9 Narcotics for pain relief00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 10 Caesarean section1150Risk Ratio (M-H, Fixed, 95% CI)0.77 [0.36, 1.64]

 11 Spontaneous vaginal birth1150Risk Ratio (M-H, Fixed, 95% CI)0.98 [0.80, 1.21]

 12 Operative vaginal birth1150Risk Ratio (M-H, Fixed, 95% CI)1.44 [0.66, 3.17]

13 Haemorrhage (>1000 mL)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

14 Severe perineal damage00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

15 Apgar < 7 at 5 min00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

16 Maternal mortality00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

17 Ruptured uterus00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

18 Maternal organ failure00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

19 Maternal admission to intensive care00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

20 Perinatal mortality00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

21 Birth asphyxia00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

22 Neonatal encephalopathy00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

23 Neonatal birth trauma00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

24 Admission to neonatal intensive care unit00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

25 Prolonged hospital stay for mothers00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

26 Prolonged hospital stay for infant00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

27 Re-admission to hospital for mothers00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

28 Re-admission to hospital for infants00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

29 Maternal distress00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

30 Mother willing to accept same intervention in future births00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

31 Maternal incontinence after 6 weeks00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

32 Childhood disability00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

33 Maternal infection with unknown treatment - not pre-specified00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

34 Infant infection with unknown treatment - not pre-specified00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

35 Very uncomfortable (not pre-specified)00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 
Table 1. Cervical technologies

Cervical technologyDescription

MechanicalCervimeter

One of the earliest technologies developed for verification of cervical dilation (vaginally) was developed by Friedman in 1956 in order to objectively measure cervical dilation and confirm the results from his previous studies (Friedman 1956b). The device adapted dressing forceps that had bulldog clips attached at one end and a hinged ruler at the other. The clips were applied to the cervix and as the cervix dilated the handles on the forceps would close. The device had a number of disadvantages described by Friedman, such as trauma to the cervix if the woman moved, discomfort for the women and a need to remain supine. Friedman concluded that digital examination was more expedient despite the accuracy of the cervimeter (Friedman 1956b). 

ElectromechanicalElectromechanical cervicometers

Friedman continued to try and modify the cervimeter by developing an electromechanical device. This device consisted of a row of retractable needles that held onto the cervix and were attached to a pair of lever arms. A small volt was applied to one of the lever arms and a graphic amplifier and recorder at another point. An alarm sounded when a preset dilation point had been reached (Friedman 1963). Again, while reportedly accurate, the machine tended to dislodge easily and Friedman concluded that digital examinations were faster and thus more useful than instruments. Electromechanical cervicometers were also introduced by other researchers (Richardson 1978; Siener 1963) but the devices were bulky, distorted the cervix and interfered with vaginal examinations and birth (Nizard 2009). 

ElectromagneticElectromagnetic cervicometer

An electromagnetic cervicometer was developed in 1977 but had problems with magnetic distortion (Kriewall 1977). When dilation was greater than 6 cm, the earth’s magnetic field interfered with the measurements. 

UltrasoundUltrasound

Ultrasound cervimetry was described in the USA (Zador 1976), Netherlands (Eijskoot 1977; Kok 1976), Spain and the UK (Molina 2010). Ultrasound was applied to the abdomen and receivers were attached to the cervix. Dupuis studied the correlation between digital vaginal and transabdominal ultrasonographic examination of the fetal head position during labour in 110 women and found in 20% of cases ultrasound and clinical results differed significantly (> 45o) (Dupuis 2005). Chou showed similar results in their study (Chou 2004). Zahalk compared transvaginal sonography and transabdominal sonography and vaginal examination in 60 women in the second stage of labour and found transvaginal sonography was the most accurate in determining position of the fetal presenting part (Zahalka 2005). 

Position tracking systems

The Barnev cervicometer (BirthTrack) uses an ultrasound-based position tracking system and sensors hooked to the cervix (Farine 2006; Sharf 2007). Developments are underway into the use of a magnetic position tracking system that uses a flat magnetic field placed under the mattress of the delivery bed  (LaborPro System) and an attachment of a sensor to the examiners index fingertip under the sterile glove. The fingertips then touch each side of the cervical margin and the distance between is measured, reflecting the cervical dilation (Nizard 2009). The LabourPro system is described as providing information on head station, head position, head descent, pelvic diameters, cervical dilation and length and 3-D visualisation of vacuum extraction (Trigmed 2009). A prospective study of this technology was undertaken in three centres (France, USA, Israel) taking 333 measurements in 188 women during the active stage of labour (excluding full dilation). Smaller errors were seen when dilation was between 0 to 4 cm and > 8 cm but there were larger errors for the 6.1 to 8 cm group. This first evaluation of the position tracking system shows limited precision (Nizard 2009).