Smoking is a big no-no for expectant mothers, as it has been known to increase the risk of autism and behavioral problems in their unborn children. But aside from these side effects, TIME reports that mothers who continue to light up may also affect their baby’s reward processing system, making the child prone to addictions in the future.

Researchers from Technische Universität Dresden in Germany compared 177 teens between ages 13 to 15 who were exposed to cigarette smoke prior to birth with 177 others. The participants were asked to complete a computer-based task while their brains were scanned by a functional magnetic resonance imaging machine. Those who performed quickly and correctly were promised a reward at the end.

Results showed that teens who were exposed to prenatal cigarette smoke had less activity in the brain's reward center called the ventral striatum, which resulted in slower reaction times. Researchers believe that the brain’s early encounter with nicotine has muted the children’s sense of satisfaction, prompting them to continue seeking their source of pleasure.

Although smoking during pregnancy doesn't necessarily mean that the child becomes an addict once he or she grows older, the harm that nicotine causes definitely outweighs the short-lived rush. If you're expecting, it may be a good idea to steer clear of cigarettes and secondhand smoke for your sake and your child's.