A new study shows the patch doesn't do much for pregnant women trying to kick the habit.
Researchers followed more than one-thousand pregnant smokers in Britain who were randomly assigned to use either a nicotine patch or an inactive placebo patch.
They found only nine-percent of patch users remained smoke-free throughout the course of their pregnancy.
That's compared to eight-percent of pregnant women using the placebo patch.
Researchers say the failure rate may be tied to the increases in metabolism that occur during pregnancy.
That increased metabolic rate causes nicotine to be processed much more quickly, which could make patches less effective.
However, researchers did find that using the patch during pregnancy doesn't appear to increase the risk of miscarriage, stillbirth, early labor or low birth weight.
The study appears in the "New England Journal of Medicine."