Effects of Lactobacillus GG yogurt to late pregnancy women in the prevention of allergy in infants

INTERVENTION: Pregnant women are given yogurt until parturition. Control group is not received yogurt during the same period of their pregnancy. CONDITION: Atopic dermatitis PRIMARY OUTCOME: infant intestinal flora; number of bacteria; species of bacteria; allergic diseases until 3y SECONDARY OUTCOME: intestinal flora of pregnant women; cytokine in human milk; cytokine in cord blood INCLUSION CRITERIA: Performs research described pregnancy 26‐27 weeks, pregnant women consent was obtained. Probiotics group and the control group, recruited to every two months.