MONDAY, Dec. 24, 2018 (HealthDay News) -- For pregnant smokers, vitamin C supplementation may improve newborn lung function, according to a study published online Dec. 7 in the American Journal of Respiratory and Critical Care Medicine.
Cindy T. McEvoy, M.D., from the Oregon Health & Science University in Portland, and colleagues conducted a randomized trial at three centers involving 251 pregnant smokers. Participants were randomly assigned at 13 to 23 weeks of gestation to vitamin C (125 women) or placebo (126 women). The primary outcome was the measurement of forced expiratory flow (FEF) at 75 percent of the expired volume (FEF75) at 3 months of age.
The researchers found that the FEF75 of infants of pregnant smokers randomly assigned to vitamin C did not differ compared with that of infants of pregnant smokers randomly assigned to placebo (200.7 versus 188.7 mL/sec; adjusted 95 percent confidence interval for difference, −3.33 to 35.64; P = 0.10); significant differences were seen for FEF50 (436.7 versus 408.5 mL/sec; adjusted 95 percent confidence interval, 6.10 to 61.30; P = 0.02) and FEF25 to 75 (387.4 versus 365.8 mL/sec; adjusted 95 percent confidence interval, 0.92 to 55.34; P = 0.04). There was a negative correlation for infant FEFs with the maternal risk alleles for the α5 nicotinic acetylcholine receptor.
"Vitamin C supplementation in pregnant women who cannot quit smoking may be a safe, inexpensive, and simple intervention to improve their offspring's pulmonary function by blocking some of the effects of in-utero smoke on lung development," the authors write.