A study published in the Journal of Maternal-Fetal and Neonatal Medicine assessed the course of vulvovaginal candidiasis (VVC), trichomoniasis, and bacterial vaginosis (BV) in pregnancy and investigated the association between these longitudinal changes and pregnancy outcomes. In all, 793 pregnant women were enrolled during the first trimester of pregnancy and were followed prospectively twice during the second and third trimesters. VVC, trichomoniasis, and BV were evaluated at each trimester of pregnancy. The trends of the three diseases and the association between the changes of trends and pregnancy outcomes were evaluated. The trend of negative at all three time points dominated for all three diseases. For VVC, a trend toward positive could not be ignored (7.5%). For BV, the distribution of other three trends (trend negative, trend positive, status random) appeared to be the same. Different trends of these three diseases were not associated with adverse pregnancy outcomes. However, women who had a trend of BV positive throughout pregnancy were more likely to suffer from amniotic fluid infection compared with women who were negative at all three time points. It thus appeared that the trend of negative throughout pregnancy was dominant for all three diseases compared with few women who were positive across their pregnancy. BV appeared to be associated with amniotic fluid infection during pregnancy.