High risk of unexpected late fetal death in monochorionic twins despite intensive ultrasound surveillance: a cohort study.

BACKGROUND: The rationale for fetal surveillance in monochorionic twin pregnancies is timely intervention to prevent the increased fetal/perinatal morbidity and mortality attributed to twin-twin transfusion syndrome and intrauterine growth restriction. We investigated the residual risk of fetal deat...

Full description

Bibliographic Details
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2005-06-01
Series:PLoS Medicine
Online Access:http://dx.doi.org/10.1371/journal.pmed.0020172
_version_ 1818366237112008704
collection DOAJ
description BACKGROUND: The rationale for fetal surveillance in monochorionic twin pregnancies is timely intervention to prevent the increased fetal/perinatal morbidity and mortality attributed to twin-twin transfusion syndrome and intrauterine growth restriction. We investigated the residual risk of fetal death after viability in otherwise uncomplicated monochorionic diamniotic twin pregnancies. METHODS AND FINDINGS: We searched an electronic database of 480 completed monochorionic pregnancies that underwent fortnightly ultrasound surveillance in our tertiary referral fetal medicine service between 1992 and 2004. After excluding pregnancies with twin-twin transfusion syndrome, growth restriction, structural abnormalities, or twin reversed arterial perfusion sequence, and monoamniotic and high-order multiple pregnancies, we identified 151 uncomplicated monochorionic diamniotic twin pregnancies with normal growth, normal liquor volume, and normal Doppler studies on fortnightly ultrasound scans. Ten unexpected intrauterine deaths occurred in seven (4.6%) of 151 previously uncomplicated monochorionic diamniotic pregnancies, within 2 wk of a normal scan, at a median gestational age of 34(+1) wk (weeks(+days); range 28(+0) to 36(+3)). Two of the five cases that underwent autopsy had features suggestive of acute late onset twin-twin transfusion syndrome, but no antenatal indicators of transfusional imbalance or growth restriction, either empirically or in a 1:3 gestation-matched case-control comparison. The prospective risk of unexpected antepartum stillbirth after 32 wk was 1/23 monochorionic diamniotic pregnancies (95% confidence interval 1/11 to 1/63). <br>CONCLUSION: Despite intensive fetal surveillance, structurally normal monochorionic diamniotic twin pregnancies without TTTS or IUGR are complicated by a high rate of unexpected intrauterine death. This prospective risk of fetal death in otherwise uncomplicated monochorionic diamniotic pregnancies after 32 wk of gestation might be obviated by a policy of elective preterm delivery, which now warrants evaluation.
first_indexed 2024-12-13T22:32:58Z
format Article
id doaj.art-462396bf1aa849dabc7db6384b020f78
institution Directory Open Access Journal
issn 1549-1277
1549-1676
language English
last_indexed 2024-12-13T22:32:58Z
publishDate 2005-06-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Medicine
spelling doaj.art-462396bf1aa849dabc7db6384b020f782022-12-21T23:29:02ZengPublic Library of Science (PLoS)PLoS Medicine1549-12771549-16762005-06-0126e172High risk of unexpected late fetal death in monochorionic twins despite intensive ultrasound surveillance: a cohort study.BACKGROUND: The rationale for fetal surveillance in monochorionic twin pregnancies is timely intervention to prevent the increased fetal/perinatal morbidity and mortality attributed to twin-twin transfusion syndrome and intrauterine growth restriction. We investigated the residual risk of fetal death after viability in otherwise uncomplicated monochorionic diamniotic twin pregnancies. METHODS AND FINDINGS: We searched an electronic database of 480 completed monochorionic pregnancies that underwent fortnightly ultrasound surveillance in our tertiary referral fetal medicine service between 1992 and 2004. After excluding pregnancies with twin-twin transfusion syndrome, growth restriction, structural abnormalities, or twin reversed arterial perfusion sequence, and monoamniotic and high-order multiple pregnancies, we identified 151 uncomplicated monochorionic diamniotic twin pregnancies with normal growth, normal liquor volume, and normal Doppler studies on fortnightly ultrasound scans. Ten unexpected intrauterine deaths occurred in seven (4.6%) of 151 previously uncomplicated monochorionic diamniotic pregnancies, within 2 wk of a normal scan, at a median gestational age of 34(+1) wk (weeks(+days); range 28(+0) to 36(+3)). Two of the five cases that underwent autopsy had features suggestive of acute late onset twin-twin transfusion syndrome, but no antenatal indicators of transfusional imbalance or growth restriction, either empirically or in a 1:3 gestation-matched case-control comparison. The prospective risk of unexpected antepartum stillbirth after 32 wk was 1/23 monochorionic diamniotic pregnancies (95% confidence interval 1/11 to 1/63). <br>CONCLUSION: Despite intensive fetal surveillance, structurally normal monochorionic diamniotic twin pregnancies without TTTS or IUGR are complicated by a high rate of unexpected intrauterine death. This prospective risk of fetal death in otherwise uncomplicated monochorionic diamniotic pregnancies after 32 wk of gestation might be obviated by a policy of elective preterm delivery, which now warrants evaluation.http://dx.doi.org/10.1371/journal.pmed.0020172
spellingShingle High risk of unexpected late fetal death in monochorionic twins despite intensive ultrasound surveillance: a cohort study.
PLoS Medicine
title High risk of unexpected late fetal death in monochorionic twins despite intensive ultrasound surveillance: a cohort study.
title_full High risk of unexpected late fetal death in monochorionic twins despite intensive ultrasound surveillance: a cohort study.
title_fullStr High risk of unexpected late fetal death in monochorionic twins despite intensive ultrasound surveillance: a cohort study.
title_full_unstemmed High risk of unexpected late fetal death in monochorionic twins despite intensive ultrasound surveillance: a cohort study.
title_short High risk of unexpected late fetal death in monochorionic twins despite intensive ultrasound surveillance: a cohort study.
title_sort high risk of unexpected late fetal death in monochorionic twins despite intensive ultrasound surveillance a cohort study
url http://dx.doi.org/10.1371/journal.pmed.0020172