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During pregnancy and infancy, it is suspected that factors both inside and outside of our bodies can have an impact on the development of our immune system.  One way of thinking is that a certain combination of these factors can lead to an imbalance in the immune system and the development of asthma.  This way of thinking also suggests that little or no exposure to bacteria and viruses during infancy leads to this imbalance in the immune system. Probiotics are bacteria that are normally found in the human intestine and have been used to provide certain health benefits, such as the prevention of diarrhea.

Babies in this study will be randomized either to receive a placebo (inactive substance) or a dietary supplement called a probiotic for the first 6 months of life. We will then follow the babies for the first three years of their lives, collect data and look for early markers of asthma, eczema or allergies.

The probiotic used in this study is Lactobacillus GG.  This bacterium is normally found in yogurt and other food products.  It is the most studied probiotic available with more than 100 studies conducted.  Lactobacillus GG is already used by many people as a supplement.

Studies also suggest that early exposure to Lactobacillus GG is associated with a decreased risk of developing eczema, a long-lasting, itchy skin rash.  Eczema is frequently found in people who have asthma.

Our study will only involve healthy infants.  We will not include infants with severe, chronic illness or those infants with intravenous (IV) lines.  In this way, we are using Lactobacillus GG in the safest possible manner.