Fetal manipulation for facilitating tests of fetal wellbeing

  • Review
  • Intervention

Authors


Abstract

Background

Manual fetal manipulation has been suggested to improve the efficiency of antepartum fetal heart rate testing.

Objectives

The objective of this review was to assess the merits or adverse effects of the use of manual fetal manipulation in conjunction with tests of fetal wellbeing.

Search methods

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2013).

Selection criteria

All published and unpublished randomised controlled trials assessing the use of fetal manipulation versus mock stimulation, no stimulation or other types of stimulation, used in conjunction with cardiotocography or other tests of fetal wellbeing.

Data collection and analysis

Three review authors independently assessed studies for inclusion, assessed trial quality and extracted data. Data were checked for accuracy. We contacted authors of published and unpublished trials for further information.

Main results

We included four trials with a total of 1280 women with 2670 episodes of participation. No trial was at low risk of bias for all domains and only two trials were at low risk of bias for both selection and attrition bias.

Fetal manual manipulation decreased the incidence of non-reactive antenatal cardiotocography test compared to mock or no stimulation. However, this was not statistically significant (average risk ratio (RR) 0.31, 95% confidence interval (CI) 0.02 to 6.20, I² = 96%; two trials, N = 2350). There was also no significant reduction in the mean testing time to achieve a reactive result (mean difference -2.29 minutes, 95% CI -9.61 minutes to 5.03 minutes, I² = 97%; two trials, N = 560).

Comparing fetal manual manipulation with vibroacoustic stimulation, there was no significant difference in the incidence of non-reactive cardiotocography or the need for contraction-stress test.

There were no data available on other outcomes such as perinatal mortality, fetal distress, maternal anxiety and gestation at delivery.

Authors' conclusions

There is insufficient evidence to support the use of manual fetal manipulation during cardiotocography or other tests of fetal wellbeing. More studies of manual fetal manipulation that utilises standardised protocol should be encouraged.

Résumé scientifique

La manipulation fœtale pour faciliter les tests du bien-être du fœtus

Contexte

La manipulation fœtale manuelle a été suggérée pour améliorer l'efficacité de la fréquence cardiaque du fœtus antepartum.

Objectifs

L'objectif de cette revue était d'évaluer les mérites ou les effets indésirables de la manipulation fœtale manuelle conjointement avec les tests du bien-être du fœtus.

Stratégie de recherche documentaire

Nous avons effectué des recherches dans le registre des essais du groupe Cochrane sur la grossesse et la naissance (le 30 septembre 2013).

Critères de sélection

Tous les essais contrôlés randomisés publiés et non publiés évaluant l'utilisation de la manipulation du fœtus par rapport à une stimulation simulée, à l'absence de stimulation ou à d'autres types de stimulation utilisés avec la cardiotocographie ou d'autres tests du bien-être du fœtus.

Recueil et analyse des données

Trois auteurs de la revue ont indépendamment évalué les études à inclure, évalué la qualité des essais et extrait les données. Des données ont été vérifiés. Nous avons contacté les auteurs des essais publiés et non publiés afin d'obtenir des informations supplémentaires.

Résultats principaux

Nous avons inclus quatre essais portant sur un total de 1280 femmes, dont 2670 séances. Aucun essai était à faible risque de biais pour tous les domaines et seuls deux essais étaient à faible risque de biais pour la sélection et le biais d'attrition.

La manipulation manuelle fœtale réduisait l'incidence de test non réactifs à des cardiotocographies prénatales par rapport à une stimulation simulée ou à l'absence de stimulation. Cependant, cela n'était pas statistiquement significatif (risque relatif moyen (RR) 0,31, intervalle de confiance (IC) à 95%, de 0,02 à 6,20, I² =96%; deux essais, N =2350). Il n'y avait également aucune réduction significative dans la moyenne de durée du test pour obtenir un résultat réactif (différence moyenne -2,29 minutes, IC à 95%, de -9,61 à 5,03 minutes, I² =97%; deux essais, N =560).

La comparaison de la manipulation manuelle du fœtus avec la stimulation vibro-acoustique ne montrait aucune différence significative dans l'incidence de la cardiotocographie non-réactive ou le besoin de tests stressants de contractions.

Il n'y avait pas de données disponibles sur les autres résultats tels que la mortalité périnatale, la détresse fœtale, l'anxiété maternelle et de gestation à l'accouchement.

Conclusions des auteurs

Il n'existe pas suffisamment de preuves pour recommander l'utilisation de la manipulation fœtale manuelle au cours de la cardiotocographie ou d'autres tests de bien-être du fœtus. D'autres études de manipulation manuelle qui utilisent des protocoles normalisés devraient être encouragées.

Plain language summary

Fetal manipulation for facilitating tests of fetal wellbeing

There is some evidence that manual fetal manipulation of unborn babies make tests of their wellbeing more effective.

Tests on unborn babies such as ultrasound and heart rate testing are carried out to check their wellbeing. As a baby's sleep periods can alter those results, various methods are used to wake the baby. Manual fetal manipulation is one of the methods. The review of trials suggests that this method could improve the efficiency of antepartum fetal heart rate testing. Research on manual fetal manipulation should take into consideration the different stimulation protocols.

Résumé simplifié

La manipulation fœtale pour faciliter les tests du bien-être du fœtus

Certaines preuves montrent que la manipulation fœtale manuelle de bébés à naître rend les tests de leur bien-être plus efficaces.

Les tests sur les bébés à naître tels que l'échographie et les tests de la fréquence cardiaque sont effectués afin de contrôler leur bien-être. Comme les périodes de sommeil du bébé peuvent modifier ces résultats, différentes méthodes sont utilisées pour le réveiller. La manipulation mnuelle du fœtus est l'une des méthodes. La revue des essais suggère que cette méthode pouvait améliorer l'efficacité des tests de fréquence cardiaque du fœtus antepartum. Des recherches supplémentaires sur la manipulation fœtale manuelle doivent prendre en compte les différents protocoles de stimulation.

Notes de traduction

Traduit par: French Cochrane Centre 14th January, 2014
Traduction financée par: Financeurs pour le Canada : Instituts de Recherche en Santé du Canada, Ministère de la Santé et des Services Sociaux du Québec, Fonds de recherche du Québec-Santé et Institut National d'Excellence en Santé et en Services Sociaux; pour la France : Ministère en charge de la Santé

Background

Various methods of stimulation have been proposed to arouse the fetus from the quiet sleep phase of the rest-activity cycle. They include a change in maternal position, physical activity, maternal glucose ingestion, sound stimulation, light stimulation and manual fetal manipulation. If the fetus can be aroused effectively, such stimulations may be useful when used in conjunction with tests of fetal wellbeing.

Manual maternal abdominal manipulation of the fetus is simple and easy to perform without additional equipment. It has been used as an adjunct to fetal heart rate testing (Keegan 1980). Arousing the fetus by abdominal manipulation could be useful when used in conjunction with tests of fetal wellbeing. In particular, the time needed to obtain a normal reactive cardiotocograph might be decreased and the number of false positive non-reactive antepartum fetal heart tracings might be lowered.

By reducing the number of non-reactive cardiotocography tests secondary to fetal quiet sleep states, fetal manipulation may be expected to reduce patient and provider anxiety and shorten overall testing time and may also allow perinatal resources to be better utilised.

Objectives

To assess the merits and adverse effects of fetal manipulation in conjunction with tests of fetal wellbeing. In particular, to assess whether the adjunctive use of fetal manipulation to alter fetal behavioural states leads to fewer false positive non-reactive tests. To assess whether the use of fetal manipulation improves perinatal outcomes, leads to greater maternal satisfaction, and is associated with costs savings and shorter testing time.

Methods

Criteria for considering studies for this review

Types of studies

All published and unpublished randomised controlled trials assessing the use of fetal manipulation versus mock stimulation, no stimulation or other types of stimulation, used in conjunction with cardiotocography or other tests of fetal wellbeing.

Types of participants

Pregnant women having antenatal assessment.

Types of interventions

Fetal manipulation versus mock stimulation, no stimulation or other types of stimulation, used in conjunction with cardiotocography or other tests of fetal wellbeing.

Types of outcome measures

Primary outcomes
  1. Incidence of non-reactive cardiotocography

  2. Testing time for fetal wellbeing

Secondary outcomes
  1. Palpated or visualised fetal movements, or movements perceived by the mother

  2. Fetal distress

  3. Gestation at delivery

  4. Maternal anxiety

  5. Maternal satisfaction

  6. Operative delivery

  7. Perinatal mortality

  8. Perinatal morbidity

  9. Maternal and fetal trauma

Search methods for identification of studies

Electronic searches

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register by contacting the Trials Search Co-ordinator (30 September 2013).

  1. monthly searches of the Cochrane Central Register of Controlled Trials (CENTRAL);

  2. weekly searches of MEDLINE;

  3. weekly searches of Embase;

  4. handsearches of 30 journals and the proceedings of major conferences;

  5. weekly current awareness alerts for a further 44 journals plus monthly BioMed Central email alerts.

Details of the search strategies for CENTRAL, MEDLINE AND Embase, the list of hand searched journals and conference proceedings, and the list of journals reviewed via the current awareness service can be found in the ‘Specialized Register’ section within the editorial information about the Cochrane Pregnancy and Childbirth Group.

Trials identified through the searching activities described above are each assigned to a review topic (or topics). The Trials Search Co-ordinator searches the register for each review using the topic list rather than keywords. 

We did not apply any language restrictions.

Data collection and analysis

For the methods used when assessing the trials identified in the previous version of this review, see Tan 2001.

For this update we used the following methods when assessing the reports identified by the updated search.

Selection of studies

All three review authors independently assessed for inclusion all the potential studies we identified as a result of the search strategy. Any disagreement would have been resolved through discussion.

Data extraction and management

We designed a form to extract data from eligible studies. We resolved discrepancies through discussion. We entered data into Review Manager software (RevMan 2012) and checked them for accuracy.

When information regarding any of the above was unclear, we attempted to contact authors of the original reports to provide further details.

Assessment of risk of bias in included studies

All three review authors independently assessed risk of bias for each study using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions ( Higgins 2011). We resolved any disagreement by discussion.

(1) Random sequence generation (checking for possible selection bias)

We described for each included study the method used to generate the allocation sequence in sufficient detail to allow an assessment of whether it should produce comparable groups.

We assessed the method as:

  • low risk of bias (any truly random process, e.g. random number table; computer random number generator);

  • high risk of bias (any non-random process, e.g. odd or even date of birth; hospital or clinic record number);

  • unclear risk of bias.   

(2) Allocation concealment (checking for possible selection bias)

We described for each included study the method used to conceal allocation to interventions prior to assignment and assessed whether intervention allocation could have been foreseen in advance of, or during recruitment, or changed after assignment.

We assessed the methods as:

  • low risk of bias (e.g. telephone or central randomisation; consecutively numbered sealed opaque envelopes);

  • high risk of bias (open random allocation; unsealed or non-opaque envelopes, alternation; date of birth);

  • unclear risk of bias.   

(3.1) Blinding of participants and personnel (checking for possible performance bias)

We described for each included study the methods used, if any, to blind study participants and personnel from knowledge of which intervention a participant received. We considered that studies were at low risk of bias if they were blinded, or if we judged that the lack of blinding would be unlikely to affect results. We assessed blinding separately for different outcomes or classes of outcomes.

We assessed the methods as:

  • low, high or unclear risk of bias for participants;

  • low, high or unclear risk of bias for personnel.

(3.2) Blinding of outcome assessment (checking for possible detection bias)

We described for each included study the methods used, if any, to blind outcome assessors from knowledge of which intervention a participant received. We assessed blinding separately for different outcomes or classes of outcomes.

We assessed methods used to blind outcome assessment as:

  • low, high or unclear risk of bias.

(4) Incomplete outcome data (checking for possible attrition bias due to the amount, nature and handling of incomplete outcome data)

We described for each included study, and for each outcome or class of outcomes, the completeness of data including attrition and exclusions from the analysis. We state whether attrition and exclusions were reported and the numbers included in the analysis at each stage (compared with the total randomised participants), reasons for attrition or exclusion where reported, and whether missing data were balanced across groups or were related to outcomes. Where sufficient information was reported, or could be supplied by the trial authors, we re-included missing data in the analyses which we undertook.

We assessed methods as:

  • low risk of bias (e.g. no missing outcome data; missing outcome data balanced across groups);

  • high risk of bias (e.g. numbers or reasons for missing data imbalanced across groups; ‘as treated’ analysis done with substantial departure of intervention received from that assigned at randomisation);

  • unclear risk of bias.

(5) Selective reporting (checking for reporting bias)

We described for each included study how we investigated the possibility of selective outcome reporting bias and what we found.

We assessed the methods as:

  • low risk of bias (where it is clear that all of the study’s pre-specified outcomes and all expected outcomes of interest to the review have been reported);

  • high risk of bias (where not all the study’s pre-specified outcomes have been reported; one or more reported primary outcomes were not pre-specified; outcomes of interest were reported incompletely and so could not be used; study fails to include results of a key outcome that would have been expected to have been reported);

  • unclear risk of bias.

(6) Other bias (checking for bias due to problems not covered by (1) to (5) above)

We described for each included study any important concerns we have about other possible sources of bias.

We assessed whether each study was free of other problems that could put it at risk of bias:

  • low risk of other bias;

  • high risk of other bias;

  • unclear whether there is risk of other bias.

(7) Overall risk of bias

We made explicit judgements about whether studies are at high risk of bias, according to the criteria given in theCochrane Handbook (Higgins 2011). With reference to (1) to (6) above, we assessed the likely magnitude and direction of the bias and whether we considered it is likely to impact on the findings. 

Measures of treatment effect

Dichotomous data

For dichotomous data, we present results as risk ratio with 95% confidence intervals. 

Continuous data

For continuous data, we used the mean difference if outcomes were measured in the same way between trials. We planned to use the standardised mean difference to combine trials that measured the same outcome, but used different methods, if required.

Unit of analysis issues

Cluster-randomised trials

We did not identify any cluster-randomised trials for inclusion in this review, but we may include trials of this type in future updates. If we do, we plan to include cluster-randomised trials in the analyses along with individually-randomised trials. Their sample sizes will be adjusted using the methods described in the Cochrane Handbook (Higgins 2011) using an estimate of the intracluster correlation co-efficient (ICC) derived from the trial (if possible), or from another source. If ICCs from other sources are used, we will report this and conduct sensitivity analyses to investigate the effect of variation in the ICC. If we identify both cluster-randomised trials and individually-randomised trials, we plan to synthesise the relevant information. We consider it reasonable to combine the results from both if there is little heterogeneity between the study designs and the interaction between the effect of intervention and the choice of randomisation unit is considered to be unlikely. We also planned to acknowledge heterogeneity in the randomisation unit and perform a sensitivity analysis to investigate the effects of the randomisation unit.

Cross-over trials

Cross-over trials were not included.

Dealing with missing data

For included studies, we noted levels of attrition. We planned to explore the impact of including studies with high levels of missing data in the overall assessment of treatment effect by using sensitivity analysis.

For all outcomes, we carried out analyses, as far as possible, on an intention-to-treat basis, i.e. we attempted to include all participants randomised to each group in the analyses, and all participants were analysed in the group to which they were allocated, regardless of whether or not they received the allocated intervention. The denominator for each outcome in each trial was the number randomised minus any participants whose outcomes were known to be missing.

Assessment of heterogeneity

We assessed statistical heterogeneity in each meta-analysis using the Tau², I² and Chi² statistics. We regarded heterogeneity as substantial if an I² was greater than 30% and either a Tau² was greater than zero, or there was a low P value (less than 0.10) in the Chi² test for heterogeneity. 

Assessment of reporting biases

In future updates, if there are 10 or more studies in the meta-analysis we will investigate reporting biases (such as publication bias) using funnel plots. We will assess funnel plot asymmetry visually.  If asymmetry is suggested by a visual assessment, we will perform exploratory analyses to investigate it.

Data synthesis

We carried out statistical analysis using the Review Manager software (RevMan 2012). We used fixed-effect meta-analysis for combining data where it was reasonable to assume that studies were estimating the same underlying treatment effect: i.e. where trials were examining the same intervention, and the trials’ populations and methods were judged sufficiently similar. If there was clinical heterogeneity sufficient to expect that the underlying treatment effects differed between trials, or if substantial statistical heterogeneity was detected, we used random-effects meta-analysis to produce an overall summary, if an average treatment effect across trials was considered clinically meaningful. The random-effects summary was treated as the average range of possible treatment effects and we planned to discuss the clinical implications of treatment effects differing between trials. If the average treatment effect was not clinically meaningful, we did not combine trials.

Where we used random-effects analyses, the results were presented as the average treatment effect with 95% confidence intervals, and the estimates of  Tau² and I².

Subgroup analysis and investigation of heterogeneity

We did not explore heterogeneity using subgroup analysis. If we identified substantial heterogeneity, we considered whether an overall summary was meaningful, and if it was, used random-effects analysis to produce it.

Sensitivity analysis

We planned to carry out sensitivity analyses to explore the effect of trial quality assessed by concealment of allocation, high attrition rates (greater than 20%), or both, with poor-quality studies being excluded from the analyses in order to assess whether this made any difference to the overall result.

Results

Description of studies

Four trials were identified from the search strategy and all four trials were eligible for inclusion.

This updated review contains four included studies with a total of 1280 women (with 2670 episodes of participation).

Included studies

The trials were conducted in California USA (Druzin 1985), Western Australia (Newnham 1990), the Netherlands (Visser 1983) and Thailand (Piyamongkol 2006a).

In Druzin's trial (Druzin 1985), participants in the intervention group underwent manual manipulation. The primary outcome was reactivity of the cardiotocography.

In Newnham's trial (Newnham 1990), two groups were compared. One group were subjected to manual fetal manipulation if the initial 20 minute trace was not reactive, and the test was continued for another 20 minutes. The other group had vibroacoustic stimulation.

In Visser's trial (Visser 1983), participants in the intervention group underwent manual manipulation.

In the Piyamongkol 2006a trial, participants were randomised to receive either manual manipulation or standard nonstress test.

Risk of bias in included studies

Please see Figure 1; Figure 2, for a summary of 'Risk of bias' assessments in included studies.

Figure 1.

.'Risk of bias' graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.

Figure 2.

'Risk of bias' summary: review authors' judgements about each risk of bias item for each included study.

Allocation

In two studies, Newnham 1990 and Visser 1983, randomisation was performed using the drawing of sealed envelopes. In the other two studies, randomisation was by alternation of hospital numbers (Druzin 1985) and by blocked randomisation (Piyamongkol 2006a). In addition, in Newnham 1990 the effectiveness of randomisation was assessed by comparisons of several parameters within the two groups, which included maternal age, parity, gestation age and primary indications.

Blinding

Only one study (Piyamongkol 2006a) reported that the fetal heart rate tracings were read blindly by one independent perinatologist.

Incomplete outcome data

In all studies 100% follow-up data were available.

Selective reporting

All expected outcomes were reported on in three of the four studies (Druzin 1985; Piyamongkol 2006a; Visser 1983). It was unclear whether selective reporting had occurred in one study (Newnham 1990).

Other potential sources of bias

No evidence of other forms of bias was apparent in any of the studies.

Effects of interventions

Four studies involving 1280 women were included.

Manual fetal manipulation versus no stimulation

Primary outcomes

Manual manipulation of the fetus reduced the incidence of non-reactive cardiotocography in comparison with no stimulation of the fetus; however, the difference did not reach statistical significance (average risk ratio (RR) 0.31, 95% confidence interval (CI) 0.02 to 6.20, Tau² = 4.45, I² = 96%; two trials, N = 2350; Analysis 1.1) and substantial heterogeneity was evident. There was also no significant reduction in the mean testing time to achieve a reactive result (mean difference (MD) -2.29 minutes, 95% CI -9.61 minutes to 5.03 minutes, Tau² = 27.03, I² = 97%; two trials, N = 560; Analysis 1.5).

Secondary outcomes

There were no data available on any of the secondary outcomes.

Manual fetal manipulation versus vibroacoustic stimulation

Primary outcomes

No significant differences were detected in the incidence of non-reactive cardiotocography in comparison with vibroacoustic stimulation of the fetus (RR 1.47, 95% CI 0.83 to 2.61; one trial, N = 300; Analysis 2.1). Newnham's trial (Newnham 1990) showed no differences in the need for contraction stress test (RR 2.67, 95% CI 0.72 to 9.86; one trial, N = 300). However, the numbers studied are small, and the results are consistent with a large increase to a small reduction in these outcomes.

Secondary outcomes

There were no data available on other secondary outcomes such as perinatal mortality, fetal distress, maternal anxiety and gestation at delivery.

Discussion

There appear to be some benefits of using fetal manual manipulation in conjunction with tests of fetal wellbeing. However, this must be weighed with respect to its effect on the predictive reliability of the tests and the safety of the procedure. At the same time, there is some discrepancy in the findings between trials identified in this review, likely due to difference in the stimulation technique and protocol. For instance, Druzin 1985 used a "rocking motion" by grasping both poles of the fetus and moving the fetus back and forth, for 60 seconds, whereas in Piyamongkol 2006a, the fetus was gently shaken left-and-right, up-and-down and forward-and-backward each procedure twice, making six manipulations. The procedure was repeated four times. The more vigorous manual manipulation could have accounted for the observed effect. More randomised controlled trials utilising a standardised protocol are needed before a recommendation can be given regarding the use of manual fetal manipulation.

Authors' conclusions

Implications for practice

There is limited evidence of benefit of simple manual fetal manipulation prior to cardiotocography testing. In view of the relatively large discrepancy in results of different trials, as well as the time needed to perform the procedure and the concern for potential trauma to the mother and fetus, this procedure is currently not recommended until more randomised controlled trials are performed to confirm these findings.

Implications for research

Trials on manual fetal manipulation should take into consideration that the stimulation frequency, technique and protocol could have an impact on the effectiveness of stimulation. Hence more attention should be paid to the standardisation and consistency of the protocol in future studies.

Acknowledgements

Thanks to Professor James Neilson who helped to initiate and conceive this review.

The National Institute for Health Research (NIHR) is the largest single funder of the Cochrane Pregnancy and Childbirth Group. The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the NIHR, NHS or the Department of Health.

Data and analyses

Download statistical data

Comparison 1. Manual fetal manipulation versus no or mock stimulation
Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size
1 Non-reactive cardiotocography22350Risk Ratio (M-H, Random, 95% CI)0.31 [0.02, 6.20]
2 Perinatal deaths00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]
3 Maternal satisfaction00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]
4 Maternal anxiety00Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]
5 Mean time of fetal heart rate remaining unreactive2560Mean Difference (IV, Random, 95% CI)-2.29 [-9.61, 5.03]
Analysis 1.1.

Comparison 1 Manual fetal manipulation versus no or mock stimulation, Outcome 1 Non-reactive cardiotocography.

Analysis 1.5.

Comparison 1 Manual fetal manipulation versus no or mock stimulation, Outcome 5 Mean time of fetal heart rate remaining unreactive.

Comparison 2. Manual fetal manipulation versus vibroacoustic stimulation
Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size
1 Non-reactive cardiotocography1300Risk Ratio (M-H, Fixed, 95% CI)1.47 [0.83, 2.61]
2 Need for contraction-stress test1300Risk Ratio (M-H, Fixed, 95% CI)2.67 [0.72, 9.86]
Analysis 2.1.

Comparison 2 Manual fetal manipulation versus vibroacoustic stimulation, Outcome 1 Non-reactive cardiotocography.

Analysis 2.2.

Comparison 2 Manual fetal manipulation versus vibroacoustic stimulation, Outcome 2 Need for contraction-stress test.

What's new

Last assessed as up-to-date: 30 September 2013.

DateEventDescription
30 September 2013New citation required but conclusions have not changed

One new study included (Piyamongkol 2006a).

This updated review is now comprised of four trials with a total of 1280 women with 2670 episodes of participation.

30 September 2013New search has been performedSearch updated. Methods updated.

History

Protocol first published: Issue 3, 1999
Review first published: Issue 4, 2001

DateEventDescription
6 July 2012AmendedSearch updated. Two reports identified (Piyamongkol 2006b; Trungtawatchai 1999).
12 February 2008AmendedConverted to new review format.
29 October 2007New search has been performedSearch updated. No new trials identified.
30 April 2006New search has been performedSearch updated. No new trials identified.
26 August 2001New citation required and conclusions have changedSubstantive amendment

Contributions of authors

KH Tan drafted and produced the protocol. KH Tan, and A Sabapathy independently drafted and discussed the initial review together. KH Tan coordinated the discussion and the final review.

In the 2013 update, KH Tan, A Sabapathy and X Wei independently reviewed the new studies, discussed and finalised the review.

Declarations of interest

None known.

Differences between protocol and review

Methods updated to current Cochrane Pregnancy and Childbirth Group standards (2013).

Notes

Update in November 2003: included new study by Visser 1983.

Characteristics of studies

Characteristics of included studies [ordered by study ID]

Druzin 1985

MethodsRandomisation method: randomised by odd or even hospital numbers with its attendant bias. Effectiveness of randomisation was assessed by comparison of various indications within the 2 groups.
ParticipantsWomen of gestation ages ranging from < 30 weeks to > 42 weeks. Majority of the tests were done because of suspected postdate pregnancy, diabetes and suspected intrauterine growth retardation. Country: USA, California. 790 women randomised.
InterventionsWomen randomised to manual stimulation group underwent manual stimulation of the fetus for 60 seconds prior to the beginning of 20 minutes of non-stress CTG test. Women randomised to non-manual stimulation group did not undergo manual manipulation prior to the beginning of 20-minute of non-stress CTG test.
OutcomesPrimary outcome: FHR reactivity. This was defined as the presence of 2 accelerations of greater than 15 beats/minute and of 15 seconds' duration or more within a 20-minute period.
NotesManual manipulation involved grasping both poles of the fetus and moving the fetus back and forth in a rocking motion.
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)High riskSequence generated by even or odd hospital number.
Allocation concealment (selection bias)High riskAllocation based on hospital number.
Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskProbably not done.
Blinding of outcome assessment (detection bias)
All outcomes
Unclear riskProbably not done.
Incomplete outcome data (attrition bias)
All outcomes
Low riskFollow-up 100%.
Selective reporting (reporting bias)Low riskAll expected outcomes reported.
Other biasLow riskNo evidence of other forms of bias.

Newnham 1990

MethodsRandomisation: randomised by draw of sealed envelopes. Effectiveness of randomisation was assessed by comparisons of several parameters within the 2 groups which include maternal ages, parities, gestational ages and primary indications.
ParticipantsWomen of at least 34 weeks' gestation. Exclusion criteria - no contraindications to contraction stress tests. Country: Western Australia. 300 women randomised.
InterventionsWomen randomised to fetal acoustic stimulation group were monitored for an initial 5 minutes. If the pattern was non-reactive, a 3-second vibratory acoustic stimulation was applied to the maternal abdomen in the region of the fetal head. The stimulus was repeated a second and a third time, also at 1-minute intervals, if satisfactory FHR accelerations had not occurred.
Women randomised to non-fetal acoustic stimulation group were monitored for an initial 20 minutes. If the trace was non-reactive, the fetus was stimulated manually and the test was continued for a further 20 minutes. If satisfactory accelerations were not found, the women were then sent for a meal. On her return, a nipple stimulation contraction stress was performed if the subsequent test remained non-reactive after a further 20 minutes.
OutcomesPrimary outcome: FHR reactivity. This was defined as the presence of 2 accelerations of greater than 15 beats/minute and of 15 seconds' duration or more within a 20-minute period. In tests in which accelerations had been provoked by fetal acoustic stimulation, the definition of reactivity required 1 of the 2 accelerations to have been unprovoked.
NotesAll tests were performed with Corometrics 115 monitors using Doppler FHR transducers. The tests were performed by specially trained fetal intensive care midwives with a nurse: patient ratio of 1:1. The vibratory acoustic stimulus had an audio frequency of 75 Hz, a sound intensity of 74 db at 1 m in air and a stimulation duration of 3 seconds. Randomisation was performed after informed consent.
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Low riskRandomisation done by draw of sealed envelopes.
Allocation concealment (selection bias)Low riskRandomisation done by draw of sealed envelopes.
Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot reported.
Blinding of outcome assessment (detection bias)
All outcomes
Unclear riskNot reported.
Incomplete outcome data (attrition bias)
All outcomes
Low riskFollow-up 100%.
Selective reporting (reporting bias)Unclear riskNot clear.
Other biasLow riskNo evidence of other form of bias.

Piyamongkol 2006a

MethodsRandomisation: 308 patients were included for 540 FHR testings, assigned to either non-stress test or manual stimulation test using blocked randomisation, 270 in each group.
ParticipantsSingleton pregnant women with gestational age of 28 or more weeks. Country: Thailand.
InterventionsIn the MST group, the presenting part of the fetus was held through the maternal abdomen by the operator with 1 hand and the upper pole of the fetus with the other hand. After 3-minute baseline recording of the FHR tracing, the fetus was then gently shaken left-and-right, up-and-down and forward-and-backward each procedure twice, making 6 manipulations. The procedure was repeated up to 3 times (4 times in total) if no qualifying acceleration was observed within 15 seconds. A new cycle of stimulation was carried out if no reactive criteria were fulfilled in 10 minutes. The same procedure was extended for another 30 minutes if no reactive criteria were achieved within 20 minutes for both MST and NST. All FHR tracings were read blindly by 1 independent perinatologist.
OutcomesTests were interpreted as reactive when there were 2 or more FHR accelerations of at least 14 beats/minute lasting at least 15 seconds in any 20-minute period. 1 prolonged FHR acceleration of at least 15 beats/minute lasting 2 or more minutes was also interpreted as reactive. The test was diagnosed as non-reactive when these criteria were not met within 40 minutes of monitoring and contraction stress test, biophysical profile, Doppler velocity or delivery determination was conducted as the hospital standard practice guideline.
Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear riskPatients were assigned to either non-stress test or manual stimulation test using blocked randomisation, 270 in each group.
Allocation concealment (selection bias)Unclear riskUnclear
Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskUnclear.
Blinding of outcome assessment (detection bias)
All outcomes
Low riskAll FHR tracings were read blindly by 1 independent perinatologist.
Incomplete outcome data (attrition bias)
All outcomes
Low riskFollow-up rate 100%.
Selective reporting (reporting bias)Low riskAll outcomes in the methods section have been reported on.
Other biasLow riskNo evidence of other forms of bias.

Visser 1983

  1. a

    CTG: cardiotocography
    FHR: fetal heart rate
    MST: manual stimulation test
    NST: non-stress test

MethodsRandomisation: randomised by draw of sealed envelopes.
Participants10 healthy nulliparous women with normal pregnancies of 37 to 40 weeks.
Interventions10 envelopes were prepared, half of which indicated that shaking procedure should be performed during the first observed FHR low variation episode and the remainder indicated that the procedure should be postponed until the second low variation episode. For each participant, an envelope was opened after the first non-reactive trace lasting 10 minutes. Shaking was performed immediately thereafter or postponed until the second such occasion. In this way 2 episodes of low variation were examined in each fetus, 1 serving as control and the other as an experimental observational period.
OutcomesPrimary outcome: FHR reactivity.
NotesManual manipulation involved external stimulation over a 20-second period by the same investigators in all participants. The stimulation consisted of strong shaking movements of the uterus, from 1 side to the other.
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Low riskRandomisation done by draw of sealed envelopes.
Allocation concealment (selection bias)Low riskRandomisation done by draw of sealed envelopes.
Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskUnclear.
Blinding of outcome assessment (detection bias)
All outcomes
Unclear riskUnclear.
Incomplete outcome data (attrition bias)
All outcomes
Low riskFollow-up 100%.
Selective reporting (reporting bias)Low riskAll outcomes in the methods section have been reported on.
Other biasLow riskNo evidence of other forms of bias.