Daily intake of vitamin C may improve the lung function of the babies born to women who are unable to quit smoking during pregnancy.
This is the conclusion of a new study at Oregon Health and Science University Doernbecher Children's Hospital.
"Smoking during pregnancy is known to adversely affect the lung development of the developing baby, causing lifelong decreased lung function and an increased risk of asthma," said Cindy McEvoy, M.D., M.C.R., neonatologist and associate professor of pediatrics at OHSU Doernbecher Children's Hospital.
"We found that babies born to pregnant smoking women who took 500 milligrams of Vitamin C daily during their pregnancy had significantly improved pulmonary function tests measured at about 48 hours after delivery," she stated.
In this pilot study, McEvoy and colleagues randomly assigned 159 pregnant women who were unable to quit smoking to either daily Vitamin C or a placebo starting before 22 weeks gestation through delivery. A group of nonsmoking pregnant women also was studied as a reference group.
The researchers measured the pulmonary function in all newborns at approximately 48 hours of age and found the newborns of smoking women who received Vitamin C supplementation had significantly improved lung function compared with the newborns of smoking women who received a placebo, as measured by standard newborn pulmonary function testing (TPTeF:TE and Crs).
In addition, the scientists found that one particular genetic variant that has been shown to increase the risk of smokers developing cancer and is associated with both a reduced ability to quit smoking and a high likelihood of relapse also seemed to intensify the harmful effects of maternal smoking on babies' lungs.
"Getting women to quit smoking during pregnancy has to be priority one, but this study provides a way to potentially help the infants born to the 50 percent of women who cannot quit smoking when pregnant," said McEvoy.
"Vitamin C supplementation may block some of the in-utero effects of smoking on fetal lung development."
"Our findings are important because improved lung function tests at birth are associated with less wheezing and asthma in childhood.
"Vitamin C is a simple, safe, and inexpensive treatment that may decrease the impact of smoking during pregnancy on the respiratory health of children," McEvoy said.
The results will be presented at the American Thoracic Society 2012 International Conference in San Francisco.