(NaturalNews) Vitamin C supplements may offset some of the damage done to the lung function of babies born to women who smoke while pregnant, according to a study conducted by researchers from the Oregon Health & Science University, Portland, and published in the journal JAMA.
The study was released online to correspond with its presentation at the American Thoracic Society International Conference. Findings from the research had also been previously presented at the annual meeting of the Pediatric Academic Societies in May 2013.
"Getting women to quit smoking during pregnancy has to be priority one, but this finding provides a way to potentially help the infants born of the roughly 50 percent of pregnant smokers who won't or just can't quit smoking no matter what is tried," researcher Eliot Spindel said.
Lifelong consequences to pregnant smoking
More than half of all smokers who become pregnant fail to quit during their pregnancy, meaning that 12 percent of pregnant women are current smokers. Yet studies have shown that children exposed to tobacco in utero suffer from hampered lung development and lifelong hindering of lung function. Such children score lower on pulmonary function tests (PFTs) at birth, are more likely to suffer from childhood asthma, and are more likely to be hospitalized for respiratory infections. Other studies have shown that children born to women who smoked during pregnancy suffer decreased pulmonary function until as late as 21 years of age.
"Although smoking cessation is the foremost goal, most pregnant smokers continue to smoke, supporting the need for a pharmacologic intervention," the researchers wrote. "This emphasizes the important opportunity of in-utero intervention. Individuals who begin life with decreased PFT measures may be at increased risk for chronic obstructive pulmonary disease."
Prior studies have indicated that vitamin C might prevent some of the negative pulmonary effects of in utero nicotine exposure. The new study was performed on 159 pregnant smokers who were fewer than 22 weeks pregnant at the study's start and who had been unable to quit smoking. The participants were randomly assigned to receive either a placebo or 500 mg of vitamin C daily. All participants were also given a daily prenatal vitamin. The children of these mothers were compared to each other, as well as to the children of 76 nonsmokers.
All children in the study were given a PFT within 72 hours of birth, measuring the infants' lung size, ease of lung motion, and ease of inhaling and exhaling. The parents were contacted again a year later to report any cases of wheezing or other respiratory problems during the first year of life.
Improved lung health
The researchers found that children of smokers who had taken vitamin C scored significantly higher on their PFTs than children of smokers given the placebo. Children in the vitamin C group were also significantly less likely to have experienced wheezing by age 1 than children in the placebo group. Among those who had experienced wheezing, children from the vitamin C group were significantly less likely to have needed medication.
By age 1, however, there was no difference in PFT scores between children in the vitamin C and placebo groups.
The researchers also found that a genetic variant known to be associated with a higher risk of smoking-induced cancer and difficulty quitting smoking (including higher risk of relapse) was also associated with more harmful effects of maternal smoking on newborn lung formation.
"Though the lung function of all babies born to smokers in our study was improved by supplemental vitamin C," lead author Cynthia T. McEvoy said, "our preliminary data suggest that vitamin C appeared to help those babies at the greatest risk of harm during their development from their mother's smoking in pregnancy."