Dataset Information

Effects of maternal smoking on body size and proportions at birth: a register-based cohort study of 1.4 million births.

ABSTRACT: OBJECTIVES:The aim of our work was to analyse the effect of maternal smoking on body size and body proportions of newborns when the mother had smoked only during the first trimester, in comparison with continued smoking after the first trimester. Furthermore, we have evaluated how growth restriction associated with maternal smoking contributes to changes in body proportions. DESIGN:Register-based cohort study SETTING: Maternal Exposure (MATEX) cohort identified from the Finnish Medical Birth Register. PARTICIPANTS:Singleton births without congenital anomalies and missing data (1.38?million) from 1 January 1991 to 31 December 2016. METHODS:Logistic regression was used to quantify the effect of maternal smoking, stratified by the maternal smoking status. OUTCOME MEASURES:Body proportions indicated by low brain-to-body ratio (defined as <10th percentile); high ponderal index and high head-to-length ratio (defined as >90th percentile); small body size for gestational age at birth (defined as weight, length or head circumference <10th percentile) and preterm birth (<37?weeks) and low birth weight (2500?g). RESULTS:Continued smoking after the first trimester was associated with high ponderal index (OR 1.26, 95%?CI 1.23 to 1.28), low brain-to-body ratio (1.11, 1.07-1.15) and high head-to-length ratio (1.22, 1.19-1.26), corresponding with absolute risks of 22%, 10% and 19%, respectively). The effects were slightly lower when smoking had been quit during the first trimester. Similar effects were seen for the body size variables and low birth weight. Preterm birth was not associated with smoking only during first trimester. CONCLUSIONS:Maternal smoking, independent of smoking duration during pregnancy, was associated with abnormal body proportions resulting from larger reduction of length and head circumference in comparison to weight. The effects of having quit smoking during the first trimester and having continued smoking after the first trimester were similar, suggesting the importance of early pregnancy as a sensitive exposure window.

SUBMITTER: Rumrich I

PROVIDER: S-EPMC7044904 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Effects of maternal smoking on body size and proportions at birth: a register-based cohort study of 1.4 million births.

Rumrich Isabell I Vähäkangas Kirsi K Viluksela Matti M Gissler Mika M de Ruyter Hanna H Hänninen Otto O

BMJ open 20200225 2

<h4>Objectives</h4>The aim of our work was to analyse the effect of maternal smoking on body size and body proportions of newborns when the mother had smoked only during the first trimester, in comparison with continued smoking after the first trimester. Furthermore, we have evaluated how growth restriction associated with maternal smoking contributes to changes in body proportions.<h4>Design</h4>Register-based cohort study SETTING: Maternal Exposure (MATEX) cohort identified from the Finnish Me ...[more]

PMID: 32102814

Similar Datasets

Project description:BackgroundEvidence remains limited about the association of maternal exposure to ambient fine particulate matter (airborne particles with an aerodynamic diameter ≤2.5 µm [PM2.5]) with fetal congenital heart defects (CHDs) in highly polluted regions, and few studies have focused on preconception exposure.MethodsUsing a nationwide surveillance-based case-control design in China, we examined the association between maternal exposure to PM2.5 during periconception (defined as 3 months before conception until 3 months into pregnancy) and risk of CHD in offspring. The study included 1 434 998 births involving 7335 CHDs from 2014 through 2017 on the basis of the National Population-Based Birth Defects Surveillance System, covering 30 provinces, municipalities, or municipal districts in China. We assigned maternal PM2.5 exposure during the periconception period to each participant using satellite-based PM2.5 concentrations at 1-km spatial resolution. Multilevel logistic regression models were used to calculate the multivariable-adjusted odds ratio and 95% CI for CHDs in offspring associated with maternal PM2.5 exposure, and the exposure-response association was investigated using restricted cubic spline analysis. Subgroup or sensitivity analyses were conducted to identify factors that may modify the association.ResultsThe average maternal exposure to PM2.5 levels across all participants was 56.51 μg/m3 (range, 10.95 to 182.13 μg/m3). For each 10 μg/m³ increase in maternal PM2.5 exposure, the risk of CHDs in offspring was increased by 2% (odds ratio, 1.02 [95% CI, 1.00 to 1.05]), and septal defect was the most influenced subtype (odds ratio, 1.04 [95% CI, 1.01 to 1.08]). The effect of PM2.5 on CHD risk was more pronounced during the preconception period. Mothers <35 years of age, those living in northern China, and those living in low-income areas were more susceptible to PM2.5 exposure than their counterparts (all P<0.05). PM2.5 exposure showed a linear association with total CHDs or specific CHD types.ConclusionsHigh maternal PM2.5 exposure, especially during the preconception period, increases risk of certain types of CHD in offspring. These findings are useful for CHD prevention and highlight the public health benefits of improving air quality in China and other highly polluted regions.

Dataset Information

Effects of maternal smoking on body size and proportions at birth: a register-based cohort study of 1.4 million births.

Publications

Effects of maternal smoking on body size and proportions at birth: a register-based cohort study of 1.4 million births.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets