There's much research out about the effects of smoking while you're pregnant, and how it may affect the health of your child. New research suggests that supplementing with Vitamin C may be beneficial to those children, and facilitate better lung function by the time they are five years old.

A recent research study published in the JAMA Pediatrics suggests that there may be benefit to children born of moms who smoke while pregnant if moms supplement Vitamin C.

Fetal exposure to cigarette smoking is a risk factor for impaired fetal lung development as well as decreased airway function and the development of asthma in the baby. Research has shown that the supplementation of Vitamin C in pregnant smokers has given benefits to their babies up until they're about a year old with increased airway function being evident.

Still, long-term Vitamin C supplementation benefits during pregnancy and the effect on babies after a year old haven't fully been analyzed until now.

In the multi-center randomized control trial, 251 pregnant women who were 15 years or older were assessed. They were current smokers who reported as having smoked ≥1 cigarette in the previous week, and were anywhere between 13- and 22 weeks pregnant.

The study did not include patients with complex medical conditions, those with unstable methods of communication or those who were currently incarcerated.

About half of the participants (125) were randomly given 500mg/d of Vitamin C, and the other 126 participants were given a placebo.

The researchers were looking at forced mid-expiratory flow (FEF25-75), which they measured by spirometry when the children of the moms were five years old. They also looked at secondary outcomes--forced expiratory volume in 1 second (FEV1) and self-reported or clinically recorded wheezing occurrences in the children when they were between four and six years old.

They found that when the children were five years old, the ones whose mothers had received Vitamin C supplementation had improved airway function--shown by improvements in FEF25-75 and significantly decreased occurrence of wheezing as compared to those in the placebo group.

Obviously, this limited study was a small sample pool, and was subjective in that there was potential misclassification of 'wheeze' since it was assessed from survey responses by the moms or caretakers. Still, the possible benefits of Vitamin C are longstanding, and observed clinical improvements and lack of adverse events in the Vitamin C group after years of follow-up was encouraging for the recommendation of Vitamin C supplementation in pregnant smokers.