Total sleep time over the 3-1/2 hours declined from an average of 84 minutes when mothers refrained from smoking to 53 minutes on the day they did smoke, a 37% reduction in infant sleep time. This was due to a shortening of the longest sleep bout, or nap, and to reductions in the amount of time spent in both active and quiet sleep.
The level of sleep disruption was directly related to the dose of nicotine infants received from their mothers milk, consistent with a role for nicotine in causing the sleep disruptions.
Infants consumed the same amount of breast milk on both days, suggesting that they were accepting of tobacco flavor in breast milk. Previous research from Mennellas laboratory has shown that infants demonstrate increased enjoyment of flavors experienced through transmission in breast milk.
Noting that children whose mothers smoke are more likely to smoke as teenagers, Mennella speculates that early experiences with tobacco flavor during breastfeeding may increase its appeal later in life.
She comments that additional studies are needed to examine the long-term developmental effects of nicotine delivered through breast milk.
An earlier study from Mennellas lab demonstrated that breast milk nicotine levels peak 30 - 60 minutes after smoking one or two cigarettes and clear by three hours after the smoking episode. Emphasizing the many benefits of breastfeeding on infant health and development, Mennella notes that lactating mothers who smoke occasionally can time their smoking episodes to minimize nicotine exposure to their child.
The present findings highlight the need for targeted smoking cessation programs that address issues relevant to lactating women. Mennella suggests that concerns about tobac
|Contact: Leslie Stein|
Monell Chemical Senses Center