Interpregnancy interval and adverse pregnancy outcomes among pregnancies following miscarriages or induced abortions in Norway (2008-2016): A cohort study

Background: The World Health Organization recommends to wait at least 6 months after miscarriage and induced abortion before becoming pregnant again to avoid complications in the next pregnancy, although the evidence-based underlying this recommendation is scarce. We aimed to investigate the risk of...

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Main Authors: Tessema, Gizachew, Håberg, S.E., Pereira, Gavin, Regan, Annette, Dunne, Jennifer, Magnus, M.C.
Format: Journal Article
Language:English
Published: PUBLIC LIBRARY SCIENCE 2022
Subjects:
Online Access:http://purl.org/au-research/grants/nhmrc/1099655
http://hdl.handle.net/20.500.11937/94246
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author Tessema, Gizachew
Håberg, S.E.
Pereira, Gavin
Regan, Annette
Dunne, Jennifer
Magnus, M.C.
author_facet Tessema, Gizachew
Håberg, S.E.
Pereira, Gavin
Regan, Annette
Dunne, Jennifer
Magnus, M.C.
author_sort Tessema, Gizachew
building Curtin Institutional Repository
collection Online Access
description Background: The World Health Organization recommends to wait at least 6 months after miscarriage and induced abortion before becoming pregnant again to avoid complications in the next pregnancy, although the evidence-based underlying this recommendation is scarce. We aimed to investigate the risk of adverse pregnancy outcomes—preterm birth (PTB), spontaneous PTB, small for gestational age (SGA) birth, large for gestational age (LGA) birth, preeclampsia, and gestational diabetes mellitus (GDM)—by interpregnancy interval (IPI) for births following a previous miscarriage or induced abortion. Methods and findings: We conducted a cohort study using a total of 49,058 births following a previous miscarriage and 23,707 births following a previous induced abortion in Norway between 2008 and 2016. We modeled the relationship between IPI and 6 adverse pregnancy outcomes separately for births after miscarriages and births after induced abortions. We used log-binomial regression to estimate unadjusted and adjusted relative risk (aRR) and 95% confidence intervals (CIs). In the adjusted model, we included maternal age, gravidity, and year of birth measured at the time of the index (after interval) births. In a sensitivity analysis, we further adjusted for smoking during pregnancy and prepregnancy body mass index. Compared to births with an IPI of 6 to 11 months after miscarriages (10.1%), there were lower risks of SGA births among births with an IPI of <3 months (8.6%) (aRR 0.85, 95% CI: 0.79, 0.92, p < 0.01) and 3 to 5 months (9.0%) (aRR 0.90, 95% CI: 0.83, 0.97, p = 0.01). An IPI of <3 months after a miscarriage (3.3%) was also associated with lower risk of GDM (aRR 0.84, 95% CI: 0.75, 0.96, p = 0.01) as compared to an IPI of 6 to 11 months (4.5%). For births following an induced abortion, an IPI <3 months (11.5%) was associated with a nonsignificant but increased risk of SGA (aRR 1.16, 95% CI: 0.99, 1.36, p = 0.07) as compared to an IPI of 6 to 11 months (10.0%), while the risk of LGA was lower among those with an IPI 3 to 5 months (8.0%) (aRR 0.84, 95% CI: 0.72, 0.98, p = 0.03) compared to an IPI of 6 to 11 months (9.4%). There was no observed association between adverse pregnancy outcomes with an IPI >12 months after either a miscarriage or induced abortion (p > 0.05), with the exception of an increased risk of GDM among women with an IPI of 12 to 17 months (5.8%) (aRR 1.20, 95% CI: 1.02, 1.40, p = 0.02), 18 to 23 months (6.2%) (aRR 1.24, 95% CI: 1.02, 1.50, p = 0.03), and ≥24 months (6.4%) (aRR 1.14, 95% CI: 0.97, 1.34, p = 0.10) compared to an IPI of 6 to 11 months (4.5%) after a miscarriage. Inherent to retrospective registrybased studies, we did not have information on potential confounders such as pregnancy intention and health-seeking bahaviour. Furthermore, we only had information on miscarriages that resulted in contact with the healthcare system. Conclusions: Our study suggests that conceiving within 3 months after a miscarriage or an induced abortion is not associated with increased risks of adverse pregnancy outcomes. In combination with previous research, these results suggest that women could attempt pregnancy soon after a previous miscarriage or induced abortion without increasing perinatal health risks.
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spelling curtin-20.500.11937-942462024-02-06T06:15:32Z Interpregnancy interval and adverse pregnancy outcomes among pregnancies following miscarriages or induced abortions in Norway (2008-2016): A cohort study Tessema, Gizachew Håberg, S.E. Pereira, Gavin Regan, Annette Dunne, Jennifer Magnus, M.C. Science & Technology Life Sciences & Biomedicine Medicine, General & Internal General & Internal Medicine NEONATAL OUTCOMES DIABETES-MELLITUS ESTIMATED RISK REGISTRY HEALTH BIRTH WOMEN TERMINATION WEIGHT Science & Technology Life Sciences & Biomedicine Medicine, General & Internal General & Internal Medicine NEONATAL OUTCOMES ESTIMATED RISK BIRTH REGISTRY HEALTH WOMEN TERMINATION WEIGHT Pregnancy Infant, Newborn Female Humans Pregnancy Outcome Abortion, Spontaneous Birth Intervals Cohort Studies Retrospective Studies Premature Birth Abortion, Induced Infant, Newborn, Diseases Diabetes, Gestational Fetal Growth Retardation Humans Abortion, Spontaneous Diabetes, Gestational Fetal Growth Retardation Premature Birth Infant, Newborn, Diseases Pregnancy Outcome Abortion, Induced Retrospective Studies Cohort Studies Pregnancy Birth Intervals Infant, Newborn Female Background: The World Health Organization recommends to wait at least 6 months after miscarriage and induced abortion before becoming pregnant again to avoid complications in the next pregnancy, although the evidence-based underlying this recommendation is scarce. We aimed to investigate the risk of adverse pregnancy outcomes—preterm birth (PTB), spontaneous PTB, small for gestational age (SGA) birth, large for gestational age (LGA) birth, preeclampsia, and gestational diabetes mellitus (GDM)—by interpregnancy interval (IPI) for births following a previous miscarriage or induced abortion. Methods and findings: We conducted a cohort study using a total of 49,058 births following a previous miscarriage and 23,707 births following a previous induced abortion in Norway between 2008 and 2016. We modeled the relationship between IPI and 6 adverse pregnancy outcomes separately for births after miscarriages and births after induced abortions. We used log-binomial regression to estimate unadjusted and adjusted relative risk (aRR) and 95% confidence intervals (CIs). In the adjusted model, we included maternal age, gravidity, and year of birth measured at the time of the index (after interval) births. In a sensitivity analysis, we further adjusted for smoking during pregnancy and prepregnancy body mass index. Compared to births with an IPI of 6 to 11 months after miscarriages (10.1%), there were lower risks of SGA births among births with an IPI of <3 months (8.6%) (aRR 0.85, 95% CI: 0.79, 0.92, p < 0.01) and 3 to 5 months (9.0%) (aRR 0.90, 95% CI: 0.83, 0.97, p = 0.01). An IPI of <3 months after a miscarriage (3.3%) was also associated with lower risk of GDM (aRR 0.84, 95% CI: 0.75, 0.96, p = 0.01) as compared to an IPI of 6 to 11 months (4.5%). For births following an induced abortion, an IPI <3 months (11.5%) was associated with a nonsignificant but increased risk of SGA (aRR 1.16, 95% CI: 0.99, 1.36, p = 0.07) as compared to an IPI of 6 to 11 months (10.0%), while the risk of LGA was lower among those with an IPI 3 to 5 months (8.0%) (aRR 0.84, 95% CI: 0.72, 0.98, p = 0.03) compared to an IPI of 6 to 11 months (9.4%). There was no observed association between adverse pregnancy outcomes with an IPI >12 months after either a miscarriage or induced abortion (p > 0.05), with the exception of an increased risk of GDM among women with an IPI of 12 to 17 months (5.8%) (aRR 1.20, 95% CI: 1.02, 1.40, p = 0.02), 18 to 23 months (6.2%) (aRR 1.24, 95% CI: 1.02, 1.50, p = 0.03), and ≥24 months (6.4%) (aRR 1.14, 95% CI: 0.97, 1.34, p = 0.10) compared to an IPI of 6 to 11 months (4.5%) after a miscarriage. Inherent to retrospective registrybased studies, we did not have information on potential confounders such as pregnancy intention and health-seeking bahaviour. Furthermore, we only had information on miscarriages that resulted in contact with the healthcare system. Conclusions: Our study suggests that conceiving within 3 months after a miscarriage or an induced abortion is not associated with increased risks of adverse pregnancy outcomes. In combination with previous research, these results suggest that women could attempt pregnancy soon after a previous miscarriage or induced abortion without increasing perinatal health risks. 2022 Journal Article http://hdl.handle.net/20.500.11937/94246 10.1371/journal.pmed.1004129 English http://purl.org/au-research/grants/nhmrc/1099655 http://purl.org/au-research/grants/nhmrc/1173991 http://creativecommons.org/publicdomain/zero/1.0/ PUBLIC LIBRARY SCIENCE fulltext
spellingShingle Science & Technology
Life Sciences & Biomedicine
Medicine, General & Internal
General & Internal Medicine
NEONATAL OUTCOMES
DIABETES-MELLITUS
ESTIMATED RISK
REGISTRY
HEALTH
BIRTH
WOMEN
TERMINATION
WEIGHT
Science & Technology
Life Sciences & Biomedicine
Medicine, General & Internal
General & Internal Medicine
NEONATAL OUTCOMES
ESTIMATED RISK
BIRTH
REGISTRY
HEALTH
WOMEN
TERMINATION
WEIGHT
Pregnancy
Infant, Newborn
Female
Humans
Pregnancy Outcome
Abortion, Spontaneous
Birth Intervals
Cohort Studies
Retrospective Studies
Premature Birth
Abortion, Induced
Infant, Newborn, Diseases
Diabetes, Gestational
Fetal Growth Retardation
Humans
Abortion, Spontaneous
Diabetes, Gestational
Fetal Growth Retardation
Premature Birth
Infant, Newborn, Diseases
Pregnancy Outcome
Abortion, Induced
Retrospective Studies
Cohort Studies
Pregnancy
Birth Intervals
Infant, Newborn
Female
Tessema, Gizachew
Håberg, S.E.
Pereira, Gavin
Regan, Annette
Dunne, Jennifer
Magnus, M.C.
Interpregnancy interval and adverse pregnancy outcomes among pregnancies following miscarriages or induced abortions in Norway (2008-2016): A cohort study
title Interpregnancy interval and adverse pregnancy outcomes among pregnancies following miscarriages or induced abortions in Norway (2008-2016): A cohort study
title_full Interpregnancy interval and adverse pregnancy outcomes among pregnancies following miscarriages or induced abortions in Norway (2008-2016): A cohort study
title_fullStr Interpregnancy interval and adverse pregnancy outcomes among pregnancies following miscarriages or induced abortions in Norway (2008-2016): A cohort study
title_full_unstemmed Interpregnancy interval and adverse pregnancy outcomes among pregnancies following miscarriages or induced abortions in Norway (2008-2016): A cohort study
title_short Interpregnancy interval and adverse pregnancy outcomes among pregnancies following miscarriages or induced abortions in Norway (2008-2016): A cohort study
title_sort interpregnancy interval and adverse pregnancy outcomes among pregnancies following miscarriages or induced abortions in norway (2008-2016): a cohort study
topic Science & Technology
Life Sciences & Biomedicine
Medicine, General & Internal
General & Internal Medicine
NEONATAL OUTCOMES
DIABETES-MELLITUS
ESTIMATED RISK
REGISTRY
HEALTH
BIRTH
WOMEN
TERMINATION
WEIGHT
Science & Technology
Life Sciences & Biomedicine
Medicine, General & Internal
General & Internal Medicine
NEONATAL OUTCOMES
ESTIMATED RISK
BIRTH
REGISTRY
HEALTH
WOMEN
TERMINATION
WEIGHT
Pregnancy
Infant, Newborn
Female
Humans
Pregnancy Outcome
Abortion, Spontaneous
Birth Intervals
Cohort Studies
Retrospective Studies
Premature Birth
Abortion, Induced
Infant, Newborn, Diseases
Diabetes, Gestational
Fetal Growth Retardation
Humans
Abortion, Spontaneous
Diabetes, Gestational
Fetal Growth Retardation
Premature Birth
Infant, Newborn, Diseases
Pregnancy Outcome
Abortion, Induced
Retrospective Studies
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/20.500.11937/94246