The role of intervening pregnancy loss in the association between interpregnancy interval and adverse pregnancy outcomes

Objective: To investigate whether intervening miscarriages and induced abortions impact the associations between interpregnancy interval after a live birth and adverse pregnancy outcomes. Design: Population-based cohort study. Setting: Norway. Participants: A total of 165 617 births to 143 916 women...

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Main Authors: Tessema, Gizachew, Håberg, S.E., Pereira, Gavin, Magnus, M.C.
Format: Journal Article
Language:English
Published: WILEY 2022
Subjects:
Online Access:http://purl.org/au-research/grants/nhmrc/1099655
http://hdl.handle.net/20.500.11937/93231
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author Tessema, Gizachew
Håberg, S.E.
Pereira, Gavin
Magnus, M.C.
author_facet Tessema, Gizachew
Håberg, S.E.
Pereira, Gavin
Magnus, M.C.
author_sort Tessema, Gizachew
building Curtin Institutional Repository
collection Online Access
description Objective: To investigate whether intervening miscarriages and induced abortions impact the associations between interpregnancy interval after a live birth and adverse pregnancy outcomes. Design: Population-based cohort study. Setting: Norway. Participants: A total of 165 617 births to 143 916 women between 2008 and 2016. Main outcome measures: We estimated adjusted relative risks for adverse pregnancy outcomes using log-binomial regression, first ignoring miscarriages and induced abortions in the interpregnancy interval estimation (conventional interpregnancy interval estimates) and subsequently accounting for intervening miscarriages or induced abortions (correct interpregnancy interval estimates). We then calculated the ratio of the two relative risks (ratio of ratios, RoR) as a measure of the difference. Results: The proportion of short interpregnancy interval (<6 months) was 4.0% in the conventional interpregnancy interval estimate and slightly increased to 4.6% in the correct interpregnancy interval estimate. For interpregnancy interval <6 months, compared with 18–23 months, the RoR was 0.97 for preterm birth (PTB) (95% confidence interval [CI] 0.83–1.13), 0.97 for spontaneous PTB (95% CI 0.80–1.19), 1.00 for small-for-gestational age (95% CI 0.86–1.14), 1.00 for large-for-gestational age (95% CI 0.90–1.10) and 0.99 for pre-eclampsia (95% CI 0.71–1.37). Similarly, conventional and correct interpregnancy intervals yielded associations of similar magnitude between long interpregnancy interval (≥60 months) and the pregnancy outcomes evaluated. Conclusion: Not considering intervening pregnancy loss due to miscarriages or induced abortions, results in negligible difference in the associations between short and long interpregnancy intervals and adverse pregnancy outcomes. Tweetable abstract: Not considering pregnancy loss in interpregnancy interval estimation resulted no meaningful differences in observed risks of adverse pregnancy outcomes.
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spelling curtin-20.500.11937-932312023-10-09T07:39:04Z The role of intervening pregnancy loss in the association between interpregnancy interval and adverse pregnancy outcomes Tessema, Gizachew Håberg, S.E. Pereira, Gavin Magnus, M.C. Science & Technology Life Sciences & Biomedicine Obstetrics & Gynecology induced abortions interpregnancy interval large-for-gestational age miscarriages pre-eclampsia preterm birth small-for-gestational age PERINATAL OUTCOMES SUBSEQUENT RISK PRETERM BIRTH ABORTION REGISTRY HEALTH IMPACT induced abortions interpregnancy interval large-for-gestational age miscarriages pre-eclampsia preterm birth small-for-gestational age Abortion, Induced Abortion, Spontaneous Birth Intervals Cohort Studies Female Humans Infant, Newborn Pregnancy Pregnancy Outcome Premature Birth Humans Abortion, Spontaneous Premature Birth Pregnancy Outcome Abortion, Induced Cohort Studies Pregnancy Birth Intervals Infant, Newborn Female Objective: To investigate whether intervening miscarriages and induced abortions impact the associations between interpregnancy interval after a live birth and adverse pregnancy outcomes. Design: Population-based cohort study. Setting: Norway. Participants: A total of 165 617 births to 143 916 women between 2008 and 2016. Main outcome measures: We estimated adjusted relative risks for adverse pregnancy outcomes using log-binomial regression, first ignoring miscarriages and induced abortions in the interpregnancy interval estimation (conventional interpregnancy interval estimates) and subsequently accounting for intervening miscarriages or induced abortions (correct interpregnancy interval estimates). We then calculated the ratio of the two relative risks (ratio of ratios, RoR) as a measure of the difference. Results: The proportion of short interpregnancy interval (<6 months) was 4.0% in the conventional interpregnancy interval estimate and slightly increased to 4.6% in the correct interpregnancy interval estimate. For interpregnancy interval <6 months, compared with 18–23 months, the RoR was 0.97 for preterm birth (PTB) (95% confidence interval [CI] 0.83–1.13), 0.97 for spontaneous PTB (95% CI 0.80–1.19), 1.00 for small-for-gestational age (95% CI 0.86–1.14), 1.00 for large-for-gestational age (95% CI 0.90–1.10) and 0.99 for pre-eclampsia (95% CI 0.71–1.37). Similarly, conventional and correct interpregnancy intervals yielded associations of similar magnitude between long interpregnancy interval (≥60 months) and the pregnancy outcomes evaluated. Conclusion: Not considering intervening pregnancy loss due to miscarriages or induced abortions, results in negligible difference in the associations between short and long interpregnancy intervals and adverse pregnancy outcomes. Tweetable abstract: Not considering pregnancy loss in interpregnancy interval estimation resulted no meaningful differences in observed risks of adverse pregnancy outcomes. 2022 Journal Article http://hdl.handle.net/20.500.11937/93231 10.1111/1471-0528.17223 English http://purl.org/au-research/grants/nhmrc/1099655 http://purl.org/au-research/grants/nhmrc/1173991 http://creativecommons.org/licenses/by-nc/4.0/ WILEY fulltext
spellingShingle Science & Technology
Life Sciences & Biomedicine
Obstetrics & Gynecology
induced abortions
interpregnancy interval
large-for-gestational age
miscarriages
pre-eclampsia
preterm birth
small-for-gestational age
PERINATAL OUTCOMES
SUBSEQUENT RISK
PRETERM BIRTH
ABORTION
REGISTRY
HEALTH
IMPACT
induced abortions
interpregnancy interval
large-for-gestational age
miscarriages
pre-eclampsia
preterm birth
small-for-gestational age
Abortion, Induced
Abortion, Spontaneous
Birth Intervals
Cohort Studies
Female
Humans
Infant, Newborn
Pregnancy
Pregnancy Outcome
Premature Birth
Humans
Abortion, Spontaneous
Premature Birth
Pregnancy Outcome
Abortion, Induced
Cohort Studies
Pregnancy
Birth Intervals
Infant, Newborn
Female
Tessema, Gizachew
Håberg, S.E.
Pereira, Gavin
Magnus, M.C.
The role of intervening pregnancy loss in the association between interpregnancy interval and adverse pregnancy outcomes
title The role of intervening pregnancy loss in the association between interpregnancy interval and adverse pregnancy outcomes
title_full The role of intervening pregnancy loss in the association between interpregnancy interval and adverse pregnancy outcomes
title_fullStr The role of intervening pregnancy loss in the association between interpregnancy interval and adverse pregnancy outcomes
title_full_unstemmed The role of intervening pregnancy loss in the association between interpregnancy interval and adverse pregnancy outcomes
title_short The role of intervening pregnancy loss in the association between interpregnancy interval and adverse pregnancy outcomes
title_sort role of intervening pregnancy loss in the association between interpregnancy interval and adverse pregnancy outcomes
topic Science & Technology
Life Sciences & Biomedicine
Obstetrics & Gynecology
induced abortions
interpregnancy interval
large-for-gestational age
miscarriages
pre-eclampsia
preterm birth
small-for-gestational age
PERINATAL OUTCOMES
SUBSEQUENT RISK
PRETERM BIRTH
ABORTION
REGISTRY
HEALTH
IMPACT
induced abortions
interpregnancy interval
large-for-gestational age
miscarriages
pre-eclampsia
preterm birth
small-for-gestational age
Abortion, Induced
Abortion, Spontaneous
Birth Intervals
Cohort Studies
Female
Humans
Infant, Newborn
Pregnancy
Pregnancy Outcome
Premature Birth
Humans
Abortion, Spontaneous
Premature Birth
Pregnancy Outcome
Abortion, Induced
Cohort Studies
Pregnancy
Birth Intervals
Infant, Newborn
Female
url http://purl.org/au-research/grants/nhmrc/1099655
http://purl.org/au-research/grants/nhmrc/1099655
http://hdl.handle.net/20.500.11937/93231