Smoking in pregnancy may raise baby's future heart risk
28 June 2011
Smoking during pregnancy - which remains as high as 15 per cent - should be viewed as a marker for raised heart and stroke risk in adult offspring, experts say.
Australian research involving 400 healthy children at age 8 years found those exposed to maternal smoking in the womb had lower levels of HDL cholesterol - so-called 'good' cholesterol - than those born to non-smokers. HDL (high-density lipoprotein) cholesterol protects against heart disease and stroke.
The average level of HDL cholesterol in children whose mother smoked in pregnancy was 1.32 mmol/L compared with 1.5 mmol/L in those whose mother did not smoke in pregnancy.
The association between maternal smoking and reduced HDL levels remained significant after taking into account passive smoking after birth, breastfeeding duration, body fat content and other factors that affect cardiovascular (heart and stroke) risk.
Lead author, cardiologist and researcher Professor David Celermajer, from the University of Sydney and Royal Prince Alfred Hospital, said while the mechanism remained unknown, it appeared that a possibly lifelong HDL deficit may be one of the unhealthy effects that maternal smoking "imprints" on a child.
"[This] may well predispose them to later heart attack or stroke. This imprinting seems to last for at least 8 years and probably a lot longer," he said in the European Heart Journal (2011, online 21 Jun).
He said the research underscored basic messages about smoking during pregnancy, but it also showed a need for closer monitoring of risk factors for heart disease in adults exposed to maternal smoking in the womb.
The difference seen in HDL may confer a "10–15 per cent higher risk of coronary disease in the children of smoking mothers ... This is an approximation only but it is the best we have," he said.
Last Reviewed: 28 June 2011
- 1. Ayer JG, Belousova E, Harmer JA, et al. Maternal cigarette smoking is associated with reduced high-density lipoprotein cholesterol in healthy 8-year-old children. Eur Heart J 2011 Jun 21. [Epub ahead of print]. doi: 10.1093/eurheartj/ehr174. http://eurheartj.oxfordjournals.org/content/early/2011/06/11/eurheartj.ehr174.abstract (accessed Jun 2011).
