Dataset Information

Maternal overweight and obesity in early pregnancy and risk of infant mortality: a population based cohort study in Sweden.

ABSTRACT:

Objective

To investigate associations between maternal overweight and obesity and infant mortality outcomes, including cause-specific mortality.

Design

Population based cohort study.

Setting and participants

1,857,822 live single births in Sweden 1992-2010.

Main outcome measures

Associations between maternal body mass index (BMI) in early pregnancy and risks of infant, neonatal, and postneonatal mortality, overall and stratified by gestational length and by causes of infant death. Odds ratios were adjusted for maternal age, parity, smoking, education, height, country of birth, and year of delivery.

Results

Infant mortality rates increased from 2.4/1000 among normal weight women (BMI 18.5-24.9) to 5.8/1000 among women with obesity grade 3 (BMI ≥ 40.0). Compared with normal weight, overweight (BMI 25.0-29.9) and obesity grade 1 (BMI 30.0-34.9) were associated with modestly increased risks of infant mortality (adjusted odds ratios 1.25 (95% confidence interval 1.16 to 1.35) and 1.37 (1.22 to 1.53), respectively), and obesity grade 2 (BMI 35.0-39.9) and grade 3 were associated with more than doubled risks (adjusted odds ratios 2.11 (1.79 to 2.49) and 2.44 (1.88 to 3.17)). In analyses stratified by preterm and term births, maternal BMI was related to risks of infant mortality primarily in term births (≥ 37 weeks), where risks of deaths due to birth asphyxia and other neonatal morbidities increased with maternal overweight and obesity. Obesity grade 2-3 was also associated with increased infant mortality due to congenital anomalies and sudden infant death syndrome.

Conclusions

Maternal overweight and obesity are associated with increased risks of infant mortality due to increased mortality risk in term births and an increased prevalence of preterm births. Maternal overweight and obesity may be an important preventable risk factor for infant mortality in many countries.

SUBMITTER: Johansson S

PROVIDER: S-EPMC4252825 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Maternal overweight and obesity in early pregnancy and risk of infant mortality: a population based cohort study in Sweden.

Johansson Stefan S Villamor Eduardo E Altman Maria M Bonamy Anna-Karin Edstedt AK Granath Fredrik F Cnattingius Sven S

BMJ (Clinical research ed.) 20141202

<h4>Objective</h4>To investigate associations between maternal overweight and obesity and infant mortality outcomes, including cause-specific mortality.<h4>Design</h4>Population based cohort study.<h4>Setting and participants</h4>1,857,822 live single births in Sweden 1992-2010.<h4>Main outcome measures</h4>Associations between maternal body mass index (BMI) in early pregnancy and risks of infant, neonatal, and postneonatal mortality, overall and stratified by gestational length and by causes of ...[more]

PMID: 25467170

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Dataset Information

Maternal overweight and obesity in early pregnancy and risk of infant mortality: a population based cohort study in Sweden.

Objective

Design

Setting and participants

Main outcome measures

Results

Conclusions

Publications

Maternal overweight and obesity in early pregnancy and risk of infant mortality: a population based cohort study in Sweden.

Similar Datasets

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