Interpregnancy intervals and adverse birth outcomes in high-income countries: An international cohort study.
BACKGROUND: Most evidence for interpregnancy interval (IPI) and adverse birth outcomes come from studies that are prone to incomplete control for confounders that vary between women. Comparing pregnancies to the same women can address this issue. METHODS: We conducted an international longitudinal c...
| Main Authors: | , , , , , , , , , , , , , , , |
|---|---|
| Format: | Journal Article |
| Language: | English |
| Published: |
PUBLIC LIBRARY SCIENCE
2021
|
| Subjects: | |
| Online Access: | http://purl.org/au-research/grants/nhmrc/1138425 http://hdl.handle.net/20.500.11937/93239 |
| _version_ | 1848765716308688896 |
|---|---|
| author | Tessema, Gizachew Marinovich, Luke Håberg, Siri E Gissler, Mika Mayo, Jonathan A Nassar, Natasha Ball, Stephen Betrán, Ana Pilar Gebremedhin, Amanuel de Klerk, Nick Magnus, Maria C Marston, Cicely Regan, Annette Shaw, Gary M Padula, Amy M Pereira, Gavin |
| author_facet | Tessema, Gizachew Marinovich, Luke Håberg, Siri E Gissler, Mika Mayo, Jonathan A Nassar, Natasha Ball, Stephen Betrán, Ana Pilar Gebremedhin, Amanuel de Klerk, Nick Magnus, Maria C Marston, Cicely Regan, Annette Shaw, Gary M Padula, Amy M Pereira, Gavin |
| author_sort | Tessema, Gizachew |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | BACKGROUND: Most evidence for interpregnancy interval (IPI) and adverse birth outcomes come from studies that are prone to incomplete control for confounders that vary between women. Comparing pregnancies to the same women can address this issue. METHODS: We conducted an international longitudinal cohort study of 5,521,211 births to 3,849,193 women from Australia (1980-2016), Finland (1987-2017), Norway (1980-2016) and the United States (California) (1991-2012). IPI was calculated based on the time difference between two dates-the date of birth of the first pregnancy and the date of conception of the next (index) pregnancy. We estimated associations between IPI and preterm birth (PTB), spontaneous PTB, and small-for-gestational age births (SGA) using logistic regression (between-women analyses). We also used conditional logistic regression comparing IPIs and birth outcomes in the same women (within-women analyses). Random effects meta-analysis was used to calculate pooled adjusted odds ratios (aOR). RESULTS: Compared to an IPI of 18-23 months, there was insufficient evidence for an association between IPI <6 months and overall PTB (aOR 1.08, 95% CI 0.99-1.18) and SGA (aOR 0.99, 95% CI 0.81-1.19), but increased odds of spontaneous PTB (aOR 1.38, 95% CI 1.21-1.57) in the within-women analysis. We observed elevated odds of all birth outcomes associated with IPI ≥60 months. In comparison, between-women analyses showed elevated odds of adverse birth outcomes for <12 month and >24 month IPIs. CONCLUSIONS: We found consistently elevated odds of adverse birth outcomes following long IPIs. IPI shorter than 6 months were associated with elevated risk of spontaneous PTB, but there was insufficient evidence for increased risk of other adverse birth outcomes. Current recommendations of waiting at least 24 months to conceive after a previous pregnancy, may be unnecessarily long in high-income countries. |
| first_indexed | 2025-11-14T11:39:40Z |
| format | Journal Article |
| id | curtin-20.500.11937-93239 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | eng |
| last_indexed | 2025-11-14T11:39:40Z |
| publishDate | 2021 |
| publisher | PUBLIC LIBRARY SCIENCE |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-932392023-10-09T03:21:23Z Interpregnancy intervals and adverse birth outcomes in high-income countries: An international cohort study. Tessema, Gizachew Marinovich, Luke Håberg, Siri E Gissler, Mika Mayo, Jonathan A Nassar, Natasha Ball, Stephen Betrán, Ana Pilar Gebremedhin, Amanuel de Klerk, Nick Magnus, Maria C Marston, Cicely Regan, Annette Shaw, Gary M Padula, Amy M Pereira, Gavin Science & Technology Multidisciplinary Sciences Science & Technology - Other Topics ASSISTED REPRODUCTIVE TECHNOLOGY IN-VITRO FERTILIZATION PERINATAL OUTCOMES PRETERM BIRTH PREGNANCY INTERVAL SUBSEQUENT RISK IMPACT METAANALYSIS INFANT Adult Birth Intervals Cohort Studies Developed Countries Female Humans Infant, Low Birth Weight Infant, Newborn Infant, Small for Gestational Age Longitudinal Studies Maternal Age Pregnancy Pregnancy Outcome Premature Birth Young Adult Humans Premature Birth Pregnancy Outcome Cohort Studies Longitudinal Studies Maternal Age Pregnancy Birth Intervals Developed Countries Adult Infant, Newborn Infant, Low Birth Weight Infant, Small for Gestational Age Female Young Adult BACKGROUND: Most evidence for interpregnancy interval (IPI) and adverse birth outcomes come from studies that are prone to incomplete control for confounders that vary between women. Comparing pregnancies to the same women can address this issue. METHODS: We conducted an international longitudinal cohort study of 5,521,211 births to 3,849,193 women from Australia (1980-2016), Finland (1987-2017), Norway (1980-2016) and the United States (California) (1991-2012). IPI was calculated based on the time difference between two dates-the date of birth of the first pregnancy and the date of conception of the next (index) pregnancy. We estimated associations between IPI and preterm birth (PTB), spontaneous PTB, and small-for-gestational age births (SGA) using logistic regression (between-women analyses). We also used conditional logistic regression comparing IPIs and birth outcomes in the same women (within-women analyses). Random effects meta-analysis was used to calculate pooled adjusted odds ratios (aOR). RESULTS: Compared to an IPI of 18-23 months, there was insufficient evidence for an association between IPI <6 months and overall PTB (aOR 1.08, 95% CI 0.99-1.18) and SGA (aOR 0.99, 95% CI 0.81-1.19), but increased odds of spontaneous PTB (aOR 1.38, 95% CI 1.21-1.57) in the within-women analysis. We observed elevated odds of all birth outcomes associated with IPI ≥60 months. In comparison, between-women analyses showed elevated odds of adverse birth outcomes for <12 month and >24 month IPIs. CONCLUSIONS: We found consistently elevated odds of adverse birth outcomes following long IPIs. IPI shorter than 6 months were associated with elevated risk of spontaneous PTB, but there was insufficient evidence for increased risk of other adverse birth outcomes. Current recommendations of waiting at least 24 months to conceive after a previous pregnancy, may be unnecessarily long in high-income countries. 2021 Journal Article http://hdl.handle.net/20.500.11937/93239 10.1371/journal.pone.0255000 eng http://purl.org/au-research/grants/nhmrc/1138425 http://purl.org/au-research/grants/nhmrc/1195716 http://purl.org/au-research/grants/nhmrc/1173991 http://purl.org/au-research/grants/nhmrc/1067066 http://purl.org/au-research/grants/nhmrc/1099655 http://purl.org/au-research/grants/nhmrc/1138425 http://purl.org/au-research/grants/nhmrc/1173991 http://creativecommons.org/publicdomain/zero/1.0/ PUBLIC LIBRARY SCIENCE fulltext |
| spellingShingle | Science & Technology Multidisciplinary Sciences Science & Technology - Other Topics ASSISTED REPRODUCTIVE TECHNOLOGY IN-VITRO FERTILIZATION PERINATAL OUTCOMES PRETERM BIRTH PREGNANCY INTERVAL SUBSEQUENT RISK IMPACT METAANALYSIS INFANT Adult Birth Intervals Cohort Studies Developed Countries Female Humans Infant, Low Birth Weight Infant, Newborn Infant, Small for Gestational Age Longitudinal Studies Maternal Age Pregnancy Pregnancy Outcome Premature Birth Young Adult Humans Premature Birth Pregnancy Outcome Cohort Studies Longitudinal Studies Maternal Age Pregnancy Birth Intervals Developed Countries Adult Infant, Newborn Infant, Low Birth Weight Infant, Small for Gestational Age Female Young Adult Tessema, Gizachew Marinovich, Luke Håberg, Siri E Gissler, Mika Mayo, Jonathan A Nassar, Natasha Ball, Stephen Betrán, Ana Pilar Gebremedhin, Amanuel de Klerk, Nick Magnus, Maria C Marston, Cicely Regan, Annette Shaw, Gary M Padula, Amy M Pereira, Gavin Interpregnancy intervals and adverse birth outcomes in high-income countries: An international cohort study. |
| title | Interpregnancy intervals and adverse birth outcomes in high-income countries: An international cohort study. |
| title_full | Interpregnancy intervals and adverse birth outcomes in high-income countries: An international cohort study. |
| title_fullStr | Interpregnancy intervals and adverse birth outcomes in high-income countries: An international cohort study. |
| title_full_unstemmed | Interpregnancy intervals and adverse birth outcomes in high-income countries: An international cohort study. |
| title_short | Interpregnancy intervals and adverse birth outcomes in high-income countries: An international cohort study. |
| title_sort | interpregnancy intervals and adverse birth outcomes in high-income countries: an international cohort study. |
| topic | Science & Technology Multidisciplinary Sciences Science & Technology - Other Topics ASSISTED REPRODUCTIVE TECHNOLOGY IN-VITRO FERTILIZATION PERINATAL OUTCOMES PRETERM BIRTH PREGNANCY INTERVAL SUBSEQUENT RISK IMPACT METAANALYSIS INFANT Adult Birth Intervals Cohort Studies Developed Countries Female Humans Infant, Low Birth Weight Infant, Newborn Infant, Small for Gestational Age Longitudinal Studies Maternal Age Pregnancy Pregnancy Outcome Premature Birth Young Adult Humans Premature Birth Pregnancy Outcome Cohort Studies Longitudinal Studies Maternal Age Pregnancy Birth Intervals Developed Countries Adult Infant, Newborn Infant, Low Birth Weight Infant, Small for Gestational Age Female Young Adult |
| url | http://purl.org/au-research/grants/nhmrc/1138425 http://purl.org/au-research/grants/nhmrc/1138425 http://purl.org/au-research/grants/nhmrc/1138425 http://purl.org/au-research/grants/nhmrc/1138425 http://purl.org/au-research/grants/nhmrc/1138425 http://purl.org/au-research/grants/nhmrc/1138425 http://purl.org/au-research/grants/nhmrc/1138425 http://hdl.handle.net/20.500.11937/93239 |