Smoking during pregnancy is known to pose risks to both baby and mother, but a new research offers a detailed evidence about the association between maternal smoking and childhood hospitalisation, as well as birth conditions which can lead to lifelong ill health. The research by the University of Glasgow provides robust estimates of the current impact of maternal smoking on infant and child health.
The research, published on Thursday in medical journal BMJ Open, offers a more detailed evidence about the association between maternal smoking in pregnancy and childhood hospitalisation, as well as birth conditions which can lead to lifelong ill health and devastating outcomes such as meningitis and Sudden Infant Death Syndrome. The authors studied births in Scotland from 1997 to 2009, with child health records followed until 2012.
“Our research provides further evidence of the harmful effects of maternal smoking in pregnancy,” said David Tappin, Professor of Clinical Trials for Children at the University of Glasgow. “This study provides evidence that could be used to estimate the current cost of maternal smoking, and to assess the cost-effectiveness of current smoking cessation strategies for pregnant women,” Tappin said.
The key findings of the study include estimates that 7 per cent of deaths in the first month of life and 22 per cent in the first year are related to maternal smoking during pregnancy. Researchers also found that 28 per cent of babies born small for gestational age, and 9 per cent born before 37 weeks, were attributable to maternal smoking. Analysing data relating to children under the age of 5 years, the study found that 12 per cent of hospital admissions for bacterial meningitis, 10 per cent for bronchiolitis, 7 per cent for asthma and 7 per cent of admissions under 1 year for ‘acute respiratory’ illness were also attributable to maternal smoking.
The rare but life-threatening condition bacterial meningitis was 49 per cent more likely to occur among children five and under born to mothers who smoked, the research noted. “We know that 25 per cent of current smokers at maternity booking do not admit to their smoking habit. Therefore the figures we have calculated may be an underestimate of the real effects of maternal smoking on outcomes,” Tappin said.
The study also found that, among babies whose mothers were current smokers during pregnancy, the odds of neonatal mortality in the first month after birth were a third higher than those whose mothers were non-smokers. The odds of infant mortality between one month and one year-old were more than two times higher among babies whose mothers were current smokers. While the odds of being born small for gestational age was also two times higher.
The researchers concluded that more than 20 per cent of post-neonatal deaths, many of which would be defined as Sudden Unexpected Deaths in Infancy (SUDI), may be related to smoking in pregnancy.