There has been a considerable volume of research into the question of whether periodontal disease in pregnant women is associated with adverse pregnancy outcomes – particularly pre-term birth (PTB) and low birth weight (LBW). Seven systematic reviews looking at associations between periodontal health and pregnancy were published between 2002 and 2008. All found some evidence for a link, but include the caveat that larger, high quality studies are required to confirm the connection between periodontal disease and adverse pregnancy outcomes.
The most recent review [Polyzos et al 2009] raises the key question as to whether periodontal disease treatment with scaling and/or root planing during pregnancy may reduce these adverse outcomes. It concludes that there is some evidence in favour of treating periodontal disease during pregnancy.
Periodontal disease is an infection of the tissue supporting the teeth that affects up to 40 per cent of adults. According to the British Dental Health Foundation, hormone changes during pregnancy make women more open to oral health problems such as gum disease. Maternal periodontal disease is associated with increased risks of PTB and LBW. In the UK there is no guidance in this area, although common practice is to undertake scaling and root planing during pregnancy but restrict anti-microbials use to acute infections only, limit the amount of radiographs and not undertake surgery until after the birth.
The mechanisms by which surgical treatment of periodontal disease might reduce PTB rate remain unknown. However, the authors suggest the benefit is likely to be related to the decline of oral cavity pathogen concentration and the consequent reduction of transportation of organisms to the amniotic fluid and chorionic membranes. In addition, a reduction in circulating inflammatory mediators produced in the oral crevice (and subsequently into the systemic circulation) of women with periodontal disease might result from surgical treatment leading to reduced exposure of genital tract tissues to these mediators. Finally, the local inflammatory response in the crevice may lead to a systemic inflammatory immune response increasing the sensitivity of immune cells in the amnion (or other genital tract tissues) to an inflammatory stimulus such as ascending bacteria from the lower to the upper genital tract; therefore, surgical treatment of periodontal disease could be beneficial simply by reducing the periodontal driver of the systemic response.
Dr Catriona Murray, academic clinical fellow in obstetrics and gynaecology at The John Radcliffe Hospital, Oxford comments: "Interestingly, the risk of pre-eclampsia, (a pregnancy related disease whose pathophysiology is thought to be related to a systemic inflammatory response), was shown to be increased in women with periodontal disease [Conde-Agudelo et al. 2008]). However, the effect of treatment of the periodontal disease was not evaluated in that meta-analysis. It should be noted that in the subgroup analysis no reduction in PTB was seen for those with more severe periodontal disease and consideration must be given to the potential dangers of bacteraemia associated with the procedure."
Professor Barbara Chadwick, Clinical Lead for NHS Evidence – oral health, adds, "This metaanalysis suggests that there is an association between periodontal disease and increased risk of PTB and LBW but the largest randomized trial included in the review did not find periodontal treatment during pregnancy to be beneficial. Weaknesses in the designs of included studies limit the conclusions that can be drawn and, frustratingly, it is not possible to make firm clinical recommendations for dental care.
"The generally cautious approach to managing pregnant patients that many dentists follow remains appropriate. However, several large randomised controlled trials are underway to test the hypothesis that periodontal treatment can reduce rates of these adverse pregnancy outcomes. If results from these trials agree with this metaanalysis, periodontal assessment and therapy could become a standard part of antenatal care."
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Polyzos NP, Polyzos IP, Mauri D, Tzioras S, Tsappi M, Cortinovis I, Casazza G. Effect of periodontal disease treatment during pregnancy on preterm birth incidence: a metaanalysis of randomized trials. American Journal of Obstetrics and Gynecolology 2009; 200(3):225-32.
Conde-Agudelo A, Villar J, Lindheimer M. Maternal infection and risk of preeclampsia: Systematic review and metaanalysis. American Journal of Obstretics and Gynecology, 2008; 198 (1): 7-22.
Vergnes JN, Sixou M. Preterm low birth weight and maternal periodontal status: a meta-analysis. American Journal of Obstetrics & Gynecology 2007; 196: 135e1-135e7.
Xiong X, Buekens P, Vastardis S, Yu SM. Periodontal disease and pregnancy outcomes: state-of-the-science. Obstetrical and Gynecological Survey 2007; 62(9):605-15.
Xiong X, Buekens P, Fraser WD, Beck J, Offenbacher S. Periodontal disease and adverse pregnancy outcomes: a systematic review. British Journal of Obstetrics and Gynaecology 2006; 113 (2): 135–143.
Khader YS, Ta'ani Q, Periodontal diseases and the risk of preterm birth and low birth weight: a meta-analysis, Journal of Periodontology 2005; 76(2): 161-5.
Scannapieco FA, Bush RB, Paju S. Periodontal disease as a risk factor for adverse pregnancy outcomes. A systematic review. Annals of Perodontology 2003; 8(1): 70-78.
Madianos PN, Bobetis GA, Kinane DF.Is periodontisis associated with an increased risk of coronary heart disease and preterm and/or low birth weight births? Journal of Clinical Periodontology 2002; 29 (Suppl. 3): 22-36.
