ObstetricsRelationship Between Interpregnancy Interval and Adverse Perinatal and Neonatal Outcomes in Northern Alberta
Section snippets
INTRODUCTION
Since the 1920s report by Woodbury,1 numerous studies in developed and developing countries have shown both short and long interpregnancy intervals to be associated with adverse birth outcomes.2 Mechanisms proposed to explain this prevailing phenomenon include maternal folate deficiency, postpartum nutritional stress, and postpartum hormonal imbalance.3., 4., 5. A systematic review of 67 observational studies (11 091 659 pregnancies) and a meta-analysis of 26 cohort and cross-sectional studies
METHODS
The Alberta Perinatal Health Program is a province-wide program that collects perinatal data from provincial delivery records for all hospital births and registered midwife attended births in Alberta.89 Patient records from this database were linked to the Alberta Health and Wellness Database—which holds extensive information on patients in the Alberta health care system9—to obtain more detailed maternal demographic information. Study data were derived only from northern Alberta, which includes
RESULTS
From the Alberta Perinatal Health Program database, a dataset was generated consisting of 185 844 records of women who had given birth to an infant in northern Alberta between January 1, 1999, and December 31, 2007. Duplicate records and records with only one delivery in the study time frame were excluded. Records with missing or inconsistent information on age, gravidity, parity, and gestational age were also excluded. This resulted in a final study cohort of 46 243 women who had two
DISCUSSION
Our study findings identified an association between both short and long interpregnancy intervals and adverse perinatal and neonatal outcomes. The interval of 12 to 17 months was associated with the lowest risk of preterm birth, LBW, SGA, perinatal death, need for NICU admission, and neonatal death. To our knowledge, this is the first Canadian study to report outcomes in this context other than SGA, and it contributes to the evidence for both perinatal and neonatal measures of well-being.
CONCLUSION
The results of our study suggest that both short and long interpregnancy intervals are associated with important perinatal and neonatal outcomes. This study corroborates the findings in previously reported studies; it also provides more detailed analyses and estimates with greater relevance to a Canadian population than existing reports, which may inform further research, policies for procedures used in prenatal risk assessment, and counselling regarding birth spacing in Canada.
ACKNOWLEDGEMENTS
We thank the Alberta Perinatal Health Program and the Alberta Health and Wellness Database for providing the data used in this study. Innie Chen is supported by a Frederick Banting and Charles Best Canada Graduate Scholarship Award from the Canadian Institutes of Health Research.
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Cited by (0)
Competing Interests: None declared.