ArticleBMJ open2020
Effects of maternal smoking on body size and proportions at birth: a register-based cohort study of 1.4 million births.
Article in BMJ open, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 22 papers, 5 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
22 citing papers in PubMed, 5 syntheses or guidelines pooled it, 32 citations in OpenAlex.
- Prevalence of preterm birth in Scandinavian countries: a systematic review and meta-analysis.The Journal of international medical research · 2023Pooled it
- Maternal Iodine Status and Birth Outcomes: A Systematic Literature Review and Meta-Analysis.Nutrients · 2023Pooled it
- Risk factors for asthma exacerbations during pregnancy: a systematic review and meta-analysis.European respiratory review : an official journal of the European Respiratory Society · 2022Pooled it
- Maternal smoking status during pregnancy and low birth weight in offspring: systematic review and meta-analysis of 55 cohort studies published from 1986 to 2020.World journal of pediatrics : WJP · 2022Pooled it
- Chained Risk Assessment for Life-Long Disease Burden of Early Exposures - Demonstration of Concept Using Prenatal Maternal Smoking.International journal of environmental research and public health · 2020Pooled it
- Maternal health behavior during pregnancy mediates the relationship between maternal stress and newborn telomere length.Brain, behavior, & immunity - health · 2026Article
- The criteria to classify body-proportionality of the small for gestational age newborn: a scoping review.BMC pregnancy and childbirth · 2025Article
- Maternal Smoking Intensity During Pregnancy and Early Adolescent Cardiovascular Health.Journal of the American Heart Association · 2025Article
- The Development of Standardized National Head Circumference Growth Charts for Jordanian Children Aged 0-5 Years: A Longitudinal and Cross-Sectional Study.Children (Basel, Switzerland) · 2025Article
- Socioeconomic determinants of low birth weight and its association with peripubertal obesity in Brazil.Frontiers in public health · 2025Article
- New Step in Understanding the Pathogenetic Mechanism of Sudden Infant Death Syndrome: Involvement of the Pontine Reticular Gigantocellular Nucleus.International journal of molecular sciences · 2024Article
- Predictive factors and adverse perinatal outcomes associated with maternal smoking status.Scientific reports · 2024Article
- Cigarette Smoking Abstinence Among Pregnant Individuals Using E-Cigarettes or Nicotine Replacement Therapy.JAMA network open · 2023Article
- Impact of BMI and smoking in adolescence and at the start of pregnancy on birth weight.BMC pregnancy and childbirth · 2023Article
- Buprenorphine-naloxone, buprenorphine, and methadone throughout pregnancy in maternal opioid use disorder.Acta obstetricia et gynecologica Scandinavica · 2023Article
- Time trends, projections, and spatial distribution of low birthweight in Australia, 2009-2030: Evidence from the National Perinatal Data Collection.Birth (Berkeley, Calif.) · 2023Article
- Head circumference from birth to five years in France: New national reference charts and comparison to WHO standards.The Lancet regional health. Europe · 2021Article
- Hokkaido birth cohort study on environment and children's health: cohort profile 2021.Environmental health and preventive medicine · 2021Article
- Effect of Grandmaternal Smoking on Body Size and Proportions at Birth.International journal of environmental research and public health · 2021Article
- Socio-demographic and motivational correlates of smoking status at term and postpartum.Health psychology report · 2021Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors at 4 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectivesThe 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.
designRegister-based cohort study
settingMaternal Exposure (MATEX) cohort identified from the Finnish Medical Birth Register.
participantsSingleton births without congenital anomalies and missing data (1.38 million) from 1 January 1991 to 31 December 2016.
methodsLogistic 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).
resultsContinued 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.
conclusionsMaternal 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.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.