Microbiota of Subgingival and Vaginal infection in Pregnancy

Objective: This study evaluated the microbiota of periodontal and gynecological infections in pregnancy, and their associations with low birth weight (LBW) and Preterm (PLBW).

Methods: Pregnant women had periodontal measurements and vaginal/cervical and subgingival samples collected at 15-23 weeks of pregnancy. 40 subgingival, vaginal/cervical species were assayed using DNA probes, and by PCR to P. gingivalis (Pg) and T. forsythia (Tf).

Results: Microbial data were available from 231 participants. 82% subjects were Hispanic, with mean age 26 (18–43) years. Infants were 9% LBW, 7% PLBW. Maternal infections were: 17% ß Streptococcus (Bstrep) infection, 17% urinary tract infection (UTI), 11% chorioamnionitis, and 38% periodontitis. No associations between periodontitis or subgingival species and prematurity were observed. Species associated with gingival bleeding included E. nodatum, C. rectus, P. gingivalis, T. forsythia, and T. denticola. UTI, chorioamnionitis, but not Bstrep infections were associated with LBW. Pg was detected in vaginal/cervical samples, but detection was not associated with LBW/PLBW. Vaginal species associated with LBW or PLBW included F. nucleatum subsp. nucleatum (Fnn), A. odontolyticus, and P. pallens. Vaginal species associated with chorioamnionitis included S. constallatus, Aa, B. fragilis, P. bivia, and Fnn. From cervical samples, S. mitis, L. salivarius, and P. melaninogenica were associated with UTI. C. curtesii, L. caseii, and C. ochracea were associated with “Bstrep” infection in vaginal samples but not the B streptococcus, S. agalactiae.

Conclusion: Microbial associations with infections in pregnancy were strongest for gingival bleeding and chorioamnionitis, and several vaginal species were associated with LBW. The DNA probe assay was valuable to screen for multiple species in over 200 subjects. Vaginal/cervical rather than subgingival infection may be more important in prematurity.

Supported by NIH/NIDCR Grant DE-015594.