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Intervention versus a conservative approach in the management of TRAP sequence: a systematic review

  • Fionnuala Mone , Priscilla Devaseelan and Stephen Ong EMAIL logo



In the management of twin reversed arterial perfusion (TRAP) sequence, we wished to (i) determine if intervention is better than a conservative approach and (ii) assess if any of the apparent adverse prognostic indicators could guide intervention.


A systematic review was conducted between 1994 and 2014. Data extracted were inspected for heterogeneity. Overall rates and confidence intervals (CIs) for each prognostic factor were calculated. Where there were comparative data, the odds ratio (OR) was calculated.


Twenty-six studies were included in the review. When all cases were considered, intervention either by cord occlusion or by ablation conferred a better survival rate compared with conservative management (OR=2.22, 95% CI 1.23–4.01, heterogeneity I2=37%, P=0.008). This difference was greater in the presence of one or more poor prognostic features (OR=8.58, 95% CI 1.47–49.96, heterogeneity I2=0%, P=0.02). Survival was better using ablative techniques compared to cord occlusion (OR=9.84, 95% CI 1.56–62.00, heterogeneity I2=0%, P=0.01).


Intervention either by cord occlusion or by ablation confers a better survival rate compared to conservative management. This appears more compelling if there are one or more poor prognostic features. Ablative techniques are superior to cord occlusion. There were insufficient data to determine which poor prognostic features should guide management.

Corresponding author: Dr. Stephen Ong, Department of Fetal Medicine, Royal Jubilee Maternity Hospital, Grosvenor Road, Belfast BT12 6BB, UK, Tel.: +44 28 9063 2496, E-mail:


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The authors stated that there are no conflicts of interest regarding the publication of this article.

Received: 2015-5-18
Accepted: 2015-8-13
Published Online: 2015-9-10
Published in Print: 2016-8-1

©2016 Walter de Gruyter GmbH, Berlin/Boston

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