The Prevalence of Members of the “Red Complex” in Pregnant Women as Revealed by PCR and BANA Hydrolysis.

Abstract

Increased levels of oestrogen and progesterone during pregnancy may lead to periodontal disease. The anaerobic Gram-negative bacteria called red complex (Porphyromonas gingivalis, Tannerella forsythensis and Treponema denticola) are frequently associated with periodontal disease. Periodontopathogens produce toxins and enzymes which can enter the bloodstream and cross the placenta to harm the foetus. The response of the mother’s immune system to infection by these periodontopathogens, brings about the release of inflammatory mediators which may trigger preterm labour or result in low birth-weight infants. The purpose of this study was to examine the prevalence of red complex, using BANA and PCR in subginginval plaque samples from pregnant women. Subgingival plaque samples were obtained from pregnant women between the ages of 17 to 45 years attending a Mitchells Plain ante-natal clinic. Plaque samples were analyzed by the enzymatic BANA-test for detection of the presence of red complex and DNA was extracted and analyzed using 16 rDNA-Polymerase Chain Reaction (PCR). Seventy-nine percent of pregnant women showed gingival index scores of ≥ 1 of which 74.24% harboured by at least one of the members of the red complex. P.gingivalis was the most prevalent of the three members of the red complex. Findings of this study confirmed a need for dental preventive measures in pregnant women and microbial monitoring of suspected periodontopathogenes. This could be achieved by joint cooperation between Maternity Obstetric Units (MOU), Dentistry and oral microbiology departments. The results of this study revealed that although PCR is more sensitive than BANA in detecting members of the red complex, BANA showed a better association with the indices used to diagnose periodontal disease.