Oral Thrush is caused by infection due to Candida Albicans yeast. This Candida fungus is normally already present in the oral cavity and the digestive tract.
Your baby may be naturally protected even before her first feeding
Nature does have a system for getting acidophilus to your baby, even before her first feeding. About halfway through pregnancy, the mother undergoes a hormonal change causing the lining of her vaginal wall to build up a lot of glycogen, which encourages the growth of lactobacilli, including Lactobacillus acidophilus. According to the website U.S. Pharmacist, the baby gets bathed with these beneficial acidophilus bacteria during a normal birth. They enter the mouth to begin populating the digestive tract. In addition to providing the first probiotics, the changes in the chemistry of the vaginal wall by the action of the lactobacilli make it more resistant to harmful bacteria. These good bacteria form colonies in the baby’s intestines and thrive on breast milk.