Re-evaluation of gestational age as a predictor for subsequent preterm birth

Background To evaluate gestational age as a predictor of subsequent preterm birth. Materials and methods This was a retrospective birth cohort study to evaluate gestational age as a predictor of subsequent preterm birth. Participants were mothers who gave birth to their first two children in Western...

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Main Authors: Pereira, Elizabeth, Tessema, Gizachew, Gissler, M., Regan, Annette, Pereira, Gavin
Format: Journal Article
Language:English
Published: PUBLIC LIBRARY SCIENCE 2021
Subjects:
Online Access:http://purl.org/au-research/grants/nhmrc/1099655
http://hdl.handle.net/20.500.11937/93228
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author Pereira, Elizabeth
Tessema, Gizachew
Gissler, M.
Regan, Annette
Pereira, Gavin
author_facet Pereira, Elizabeth
Tessema, Gizachew
Gissler, M.
Regan, Annette
Pereira, Gavin
author_sort Pereira, Elizabeth
building Curtin Institutional Repository
collection Online Access
description Background To evaluate gestational age as a predictor of subsequent preterm birth. Materials and methods This was a retrospective birth cohort study to evaluate gestational age as a predictor of subsequent preterm birth. Participants were mothers who gave birth to their first two children in Western Australia, 1980-2015 (N = 255,151 mothers). For each week of final gestational age of the first birth, we calculated relative risks (RR) and absolute risks (AR) of subsequent preterm birth defined as final gestational age before 28, 32, 34 and <37 weeks. Risks were unadjusted to preserve risk factor profiles at each week of gestation. Results The relative risks of second birth before 28, 32, and 34 weeks' gestation were all approximately twenty times higher for mothers whose first birth had a gestational age of 22 to 30 weeks compared to those whose first birth was at 40 weeks' gestation. The absolute risks of second birth before 28, 32, and 34 weeks' gestation for these mothers had upper confidence limits that were all less than 16.74%. The absolute risk of second birth before 37 weeks was highest at 32.11% (95% CI: 30.27, 34.02) for mothers whose first birth was 22 to 30 weeks' gestation. For all gestational ages of the first child, the lowest quartile and median gestational age of the second birth were at least 36 weeks and at least 38 weeks, respectively. Sensitivity and positive predictive values were all below 35%. Conclusion Relative risks of early subsequent birth increased markedly with decreasing gestational age of the first birth. However, absolute risks of clinically significant preterm birth (<28 weeks, <32 weeks, <34 weeks), sensitivity and positive predictive values remained low. Early gestational age is a strong risk factor but a poor predictor of subsequent preterm birth.
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spelling curtin-20.500.11937-932282023-10-09T00:10:51Z Re-evaluation of gestational age as a predictor for subsequent preterm birth Pereira, Elizabeth Tessema, Gizachew Gissler, M. Regan, Annette Pereira, Gavin Science & Technology Multidisciplinary Sciences Science & Technology - Other Topics RECURRENCE Adult Female Gestational Age Humans Obstetric Labor, Premature Pregnancy Premature Birth Retrospective Studies Risk Factors Western Australia Young Adult Humans Premature Birth Risk Factors Retrospective Studies Gestational Age Pregnancy Adult Western Australia Female Obstetric Labor, Premature Young Adult Background To evaluate gestational age as a predictor of subsequent preterm birth. Materials and methods This was a retrospective birth cohort study to evaluate gestational age as a predictor of subsequent preterm birth. Participants were mothers who gave birth to their first two children in Western Australia, 1980-2015 (N = 255,151 mothers). For each week of final gestational age of the first birth, we calculated relative risks (RR) and absolute risks (AR) of subsequent preterm birth defined as final gestational age before 28, 32, 34 and <37 weeks. Risks were unadjusted to preserve risk factor profiles at each week of gestation. Results The relative risks of second birth before 28, 32, and 34 weeks' gestation were all approximately twenty times higher for mothers whose first birth had a gestational age of 22 to 30 weeks compared to those whose first birth was at 40 weeks' gestation. The absolute risks of second birth before 28, 32, and 34 weeks' gestation for these mothers had upper confidence limits that were all less than 16.74%. The absolute risk of second birth before 37 weeks was highest at 32.11% (95% CI: 30.27, 34.02) for mothers whose first birth was 22 to 30 weeks' gestation. For all gestational ages of the first child, the lowest quartile and median gestational age of the second birth were at least 36 weeks and at least 38 weeks, respectively. Sensitivity and positive predictive values were all below 35%. Conclusion Relative risks of early subsequent birth increased markedly with decreasing gestational age of the first birth. However, absolute risks of clinically significant preterm birth (<28 weeks, <32 weeks, <34 weeks), sensitivity and positive predictive values remained low. Early gestational age is a strong risk factor but a poor predictor of subsequent preterm birth. 2021 Journal Article http://hdl.handle.net/20.500.11937/93228 10.1371/journal.pone.0245935 English http://purl.org/au-research/grants/nhmrc/1099655 http://purl.org/au-research/grants/nhmrc/1173991 http://creativecommons.org/licenses/by/4.0/ PUBLIC LIBRARY SCIENCE fulltext
spellingShingle Science & Technology
Multidisciplinary Sciences
Science & Technology - Other Topics
RECURRENCE
Adult
Female
Gestational Age
Humans
Obstetric Labor, Premature
Pregnancy
Premature Birth
Retrospective Studies
Risk Factors
Western Australia
Young Adult
Humans
Premature Birth
Risk Factors
Retrospective Studies
Gestational Age
Pregnancy
Adult
Western Australia
Female
Obstetric Labor, Premature
Young Adult
Pereira, Elizabeth
Tessema, Gizachew
Gissler, M.
Regan, Annette
Pereira, Gavin
Re-evaluation of gestational age as a predictor for subsequent preterm birth
title Re-evaluation of gestational age as a predictor for subsequent preterm birth
title_full Re-evaluation of gestational age as a predictor for subsequent preterm birth
title_fullStr Re-evaluation of gestational age as a predictor for subsequent preterm birth
title_full_unstemmed Re-evaluation of gestational age as a predictor for subsequent preterm birth
title_short Re-evaluation of gestational age as a predictor for subsequent preterm birth
title_sort re-evaluation of gestational age as a predictor for subsequent preterm birth
topic Science & Technology
Multidisciplinary Sciences
Science & Technology - Other Topics
RECURRENCE
Adult
Female
Gestational Age
Humans
Obstetric Labor, Premature
Pregnancy
Premature Birth
Retrospective Studies
Risk Factors
Western Australia
Young Adult
Humans
Premature Birth
Risk Factors
Retrospective Studies
Gestational Age
Pregnancy
Adult
Western Australia
Female
Obstetric Labor, Premature
Young Adult
url http://purl.org/au-research/grants/nhmrc/1099655
http://purl.org/au-research/grants/nhmrc/1099655
http://hdl.handle.net/20.500.11937/93228