George Macones, M.D., OB/GYN with Washington University in St. Louis, says vitamin D also plays a role in the development of the immune system and healthy lungs.Some researchers believe low levels of the vitamin during pregnancy, when an infant’s lungs are still developing, may increase the risk for asthma in the child. The hypothesis is further supported by studies that show asthma rates in New England (where vitamin D levels are more likely to be inadequate due to low levels of sunlight in the winter) are the highest in the country.
Investigators now want to find out if supplementing a pregnant woman’s diet with high doses of vitamin D may decrease the incidence of asthma in offspring. Macones says the study is enrolling pregnant women with a history of asthma and those for whom the baby’s father has a history of asthma.
Half the women will get a high dose of vitamin D (4000 iu of vitamin D3, or colecalciferol) and the standard prenatal vitamin. The other half will take the prenatal vitamin and a placebo.
After the babies are born, the children will have regular follow-ups with a pediatrician to look for signs of asthma in the first few years of life. It will take several years until researchers have enough follow-up data. However, investigators are hopeful the study will determine if supplementation of high doses of vitamin D are safe for mom and baby and reduce the future risk of asthma for the baby.
The study is taking place in St. Louis, Boston and San Diego. For more information, go here .