Evolution of resident oral bacterial biota in BALB/c mice during pregnancy and lactation

To assess the influence of pregnancy and lactation on the oral microbial ecology of BALB/c mice, we followed the distribution of the predominant oral bacteria of four groups of these mice during these two periods. Compared with nonpregnant control female mice of the same age maintained under the same conditions, the distribution of the resident oral bacterial species differed significantly only during the lactation period (8–16 days after parturition). This difference could possibly be attributed to hormonal influences and/or grooming habits.