Changes in Vaginal Flora During Pregnancy and Association With Preterm Birth

Aerobic vaginitis: Abnormal vaginal flora entity that is distinct from bacterial vaginosis

“…The most recent, large NICHD study on women at low risk of pregnancy complications was unable to show any effect of the presence of bacterial vaginosis and its treatment on the rate of preterm birth, preterm rupture of membranes or chorioamnionitis [13]. Yet several groups had formerly found bacterial vaginal flora to have an important impact on these complications [6,7,[14][15][16]. Upon close scrutiny, the data often revealed a different effect if women with abnormal flora were divided into those with full-blown anaerobic bacterial flora on the one hand, and those with so-called dintermediateT flora on the other [6,7].…”

“…Yet several groups had formerly found bacterial vaginal flora to have an important impact on these complications [6,7,[14][15][16]. Upon close scrutiny, the data often revealed a different effect if women with abnormal flora were divided into those with full-blown anaerobic bacterial flora on the one hand, and those with so-called dintermediateT flora on the other [6,7]. Severe complications such as midtrimester pregnancy losses, chorioamnionitis and even first trimester abortions were linked to the latter flora and mycoplasmata [6,14,15].…”

“…Severe complications such as midtrimester pregnancy losses, chorioamnionitis and even first trimester abortions were linked to the latter flora and mycoplasmata [6,14,15]. McDonald et al found E. coli and GBS to be important pathogens alongside the classical bacterial vaginosis organisms [7], and we reported that abnormal flora, but not full-blown BV, was associated with preterm birth [9,16]. Hence, we suggested that a second abnormality of the vaginal flora should be considered, now coined daerobic vaginitisT [1].…”

“…The problem is that some forms of abnormal vaginal microflora are neither normal, nor can they be called BV. Such forms of abnormal flora have been termed dintermediate floraT in some studies, or have been included with full-blown BV in others [6][7][8]. This type of undefined abnormal flora (not BV) may, however, be of crucial importance in pregnant women at risk of preterm delivery [6,8].…”

Bacterial vaginosis: Culture- and PCR-based characterizations of a complex polymicrobial disease’s pathobiology

“…In approximately 40% of women, BV is asymptomatic. Symptomatic and asymptomatic disease are associated with serious complications related to the upper genital tract, increasing the risk of preterm delivery [4,5], first trimester miscarriage, amnionitis, postpartum and postabortion endometritis, pelvic inflammatory disease, and post-hysterectomy vaginal cuff infections. They are also associated with risk of contracting other sexually transmitted pathogens including Neisseria gonorrhoeae [6].…”