- January 9, 2014

Science Daily/Elsevier

Smoking during pregnancy is linked to numerous negative outcomes, including low birth weight, sudden infant death syndrome, and increased risk for attention deficit disorder, conduct disorder, and nicotine use in offspring.

Despite this extensive literature, it is estimated that 13%-30% of women in the United States continue to smoke while pregnant. Now, a new 40-year longitudinal study provides strong evidence that prenatal exposure to maternal stress hormones predicts nicotine dependence later in life -- but only for daughters.

Smoking during pregnancy is linked to numerous negative outcomes, including low birth weight, sudden infant death syndrome, and increased risk for attention deficit disorder, conduct disorder, and nicotine use in offspring. Despite this extensive literature, it is estimated that 13%-30% of women in the United States continue to smoke while pregnant.

Now, a new 40-year longitudinal study, published in Biological Psychiatry, provides strong evidence that prenatal exposure to maternal stress hormones predicts nicotine dependence later in life -- but only for daughters. It also confirms previous research that babies born to moms who smoked when pregnant have an increased risk of nicotine addiction in adulthood.

The findings revealed that in female but not male offspring, elevated prenatal cortisol exposure and exposure to maternal smoking during pregnancy were associated with increased rates of nicotine dependence as adults. No links were found between elevated prenatal testosterone exposure and adult nicotine dependence. There were also no findings among male offspring.

"Our findings highlight the particular vulnerability of daughters to long-term adverse outcomes following maternal stress and smoking during pregnancy. We don't yet know why this is, but possible mechanisms include sex differences in stress hormone regulation in the placenta and adaptation to prenatal environmental exposures," added Stroud.

"Also, cortisol and nicotine may affect developing male and female brains differently. Furthermore, if daughters of smoking mothers are more likely to grow up nicotine dependent, the result is dangerous cycle of intergenerational transmission of nicotine addiction."

"These new data may help us to focus our attention on individuals at greatest risk for later smoking," said Dr. John Krystal, Editor of Biological Psychiatry. "It is interesting that female, but not male, offspring seemed to be at greatest risk. Sex differences in the vulnerability to smoking are important and merit further study."

http://www.sciencedaily.com/releases/2014/01/140109091934.htm