Epidemiological reviews quantifying the relationship between heaviness of smoking in pregnancy and infant outcomes

Smoking in pregnancy causes a lot of harm, including babies being born very small and poorly, needing hospital special care.

National Health Service (NHS) stop smoking support includes nicotine replacement therapy (NRT, for example, patches, gum, inhalators) and helps pregnant women to stop smoking. However, most women cannot stop, and no further help is offered to them. For these women, cutting down is very likely to be much better for them and their babies than ‘smoking as usual’, but they are not currently helped to do this. When non-pregnant people use NRT to cut down, many go on to stop smoking for good, even though they weren’t thinking about stopping when they started using NRT.

Researchers do not know which outcomes for the mother and baby might be affected by cutting down smoking in pregnancy, or by how much. For this study we will search for research papers describing the relationship between the number of cigarettes women smoke during pregnancy, their birth outcomes and how healthy their baby is. We aim to discover whether how heavily women smoke in pregnancy affects their health, and the health of their baby. Our findings will be used to adapt a developed economic model which will then be used to evaluate the cost-effectiveness of using NRT to reduce smoking in pregnancy. We will group the studies’ findings to work out how much a treatment which involves using NRT to cut down could help pregnant women, and cost or save the NHS money.

Impact

Findings from this study will improve our understanding of how cutting down smoking in pregnancy could affect the health of the mother and baby. This study will help us decide if cutting down smoking in pregnancy is safe and can improve the health of mothers and babies. We will use these findings, together with our other research, to help us design future studies to test whether, for pregnant women who cannot stop smoking, using NRT to smoke fewer cigarettes is better than ‘smoking as normal’.

At the moment the NHS does not offer support to women who are unable to stop smoking altogether. If the NHS used NRT to help pregnant women cut down smoking, an extra 72,000 women and babies could be supported annually and many of these women would go on to stop smoking completely. This radical change to NHS care would deliver better health for babies and women.

Amount awarded: £60,209