Journal of Pharmacy And Bioallied Sciences

: 2017  |  Volume : 9  |  Issue : 5  |  Page : 50--54

Maternal risk factors and periodontal disease: A cross-sectional study among postpartum mothers in Tamil Nadu

Rohini Govindasamy1, Manikandan Dhanasekaran1, Sheeja S Varghese2, VR Balaji2, B Karthikeyan1, Ananthi Christopher3,  
1 Department of Periodontics, CSI College of Dental Sciences and Research, Madurai, Tamil Nadu, India
2 Department of Periodontics, Saveetha University, Chennai, Tamil Nadu, India
3 Department of Pedodontics, CSI College of Dental Sciences and Research, Madurai, Tamil Nadu, India

Correspondence Address:
Rohini Govindasamy
Department of Periodontics, CSI College of Dental Sciences and Research, 129, East Veli Street, Madurai, Tamil Nadu


Background and Aim: It is inconclusive that periodontitis is an independent risk factor for adverse pregnancy outcomes. This study aims to investigate the association between maternal periodontitis and preterm and/or low birth weight babies. Settings and Design: This was a prospective cross-sectional study. After prior informed consent, 3500 postpartum mothers were selected from various hospitals in Tamil Nadu and categorized into the following groups: group-1 – Normal term normal birth weight (n = 1100); Group-2 – Preterm normal birth weight (n = 400); Group-3 – preterm low birth weight (PTLBW) (n = 1000); and Group-4 – Normal term low birth weight (n = 1000). Periodontal examination was done, and risk factors were ascertained by means of questionnaire and medical records. Statistical Analysis: Comparison between case groups and control groups were done, odds ratio (OR) was calculated, and statistical significance were assessed by Chi-square tests. To control for the possible confounders, all variables with P < 0.05 were selected and entered into multivariate regression model, and OR and 95% confidence limits were again estimated. SPSS-15 software was used. Results: Periodontitis was diagnosed in 54.8%, 52.3%, 53.8%, 59.4%, respectively. On comparison between the groups, none of periodontal parameters showed significant association except for the crude association observed in Group-4 for mild periodontitis (OR - 1.561; P = 0.000) and PTLBW. Conclusion: Periodontitis is not a significant independent risk factor, and obstetric factors contribute a major risk for preterm and/or low birth weight babies

How to cite this article:
Govindasamy R, Dhanasekaran M, Varghese SS, Balaji V R, Karthikeyan B, Christopher A. Maternal risk factors and periodontal disease: A cross-sectional study among postpartum mothers in Tamil Nadu.J Pharm Bioall Sci 2017;9:50-54

How to cite this URL:
Govindasamy R, Dhanasekaran M, Varghese SS, Balaji V R, Karthikeyan B, Christopher A. Maternal risk factors and periodontal disease: A cross-sectional study among postpartum mothers in Tamil Nadu. J Pharm Bioall Sci [serial online] 2017 [cited 2022 Aug 16 ];9:50-54
Available from:

Full Text


Preterm low birth weight (PTLBW) is a problem encountered in most world communities at varying levels of prevalence. The international definition of low birth weight adopted by the 29th world health assembly in 1976 is a birth weight <2500 g. Low birth weight increases the risk of infant mortality and morbidity. Various risk factors have been associated with the delivery of PTLBW infants which include maternal age (<18 years or <35 years), height, weight, socioeconomic status, ethnicity, smoking, and nutritional status. In addition, parity, birth interval, previous complication, prenatal care, hypertension, diabetes, genitourinary infection, and multiple pregnancy may also be important.[1],[2]

There is mounting evidence that infections that are remote to the fetal placental unit can affect the birth outcomes. Periodontal disease, a Gram-negative anaerobic infection, has a potential to cause deleterious effect on mother and fetus leading to PTLBW infants. Studies showing the association between maternal periodontal disease and adverse birth outcomes have demonstrated varied results.[3],[4] The inconsistency of these findings was attributed to the methodological limitations either because of a small sample size or exclusion of possible confounders or due to the lack of uniform criteria for defining periodontal disease.[5] Hence, the aim of the present study was to evaluate the possible association between maternal periodontal disease and PTLBW in babies using a large sample size, including all possible confounders and using standardized criteria for defining and assessing periodontal status.

 Materials And Methods

Study design

The study design was cross-sectional and included 3500 postpartum mothers aged 18–35 years selected from government and private hospitals in Tamil Nadu, from November 2009 and May 2010. Assuming the prevalence of PTLBW as 10%, the sample size needed for 95% confidence limit with an accuracy of 10% was found to be 3500. Mothers with singleton gestation and in the age group of 18–35 years were included in the study. Women who are epileptic, HIV infection, any medical condition requiring antibiotic prophylaxis for periodontal probing, history of any bleeding disorders, or any contraindication for probing were excluded from the study. Ethical clearance was obtained from the institutional review board, and permission to conduct the study was obtained from the respective deans of hospitals. Participants were enrolled in the study after signing informed consent form.

Sociodemographic and clinical data

Information about the study groups was obtained through questionnaire, and periodontal status of the participants was assessed and entered in individual forms for each patient. The mothers were grouped into the following categories: Group-I: Normal term normal birth weight (infant weighing ≥2500 g and born after 37 weeks of gestation) (n = 1100) (control group); Group-2: Preterm normal birth weight (infant weighing ≥2500 g and born before 37 weeks of gestation) (n = 400); Group-3: PTLBW (infant weighing <2500 g and born before 37 weeks of gestation) (n = 1000); and Group-4: Normal term low birth weight (infant weighing <2500 g and born after 37 weeks of gestation) (n = 1000).

Periodontal examination

Full mouth periodontal examination was carried out on mothers in the supine position on the hospital bed within 3 days of delivery. The examination comprised of recording the following parameters: (a) Plaque Index(Silness and Loe ) (b) Papillary Bleeding Index (Muhlemann); and (c) Probing depth and clinical attachment loss measured using Williams's periodontal probe on six sites for each teeth. Bleeding index and plaque index were measured on four gingival areas (mesial, distal, buccal, lingual).

Periodontitis was determined to be present, when three sites in different teeth with probing depth of 4 mm or more and loss of three or more millimeters of clinical attachment were available. The presence of gingival recession was registered but excluded for diagnostic purposes when present in the buccal and lingual surfaces. For analytical purpose, periodontitis severity was assessed based on Bassani et al.'s[6] criteria which were categorized as mild, moderate, and severe. Bleeding score and plaque scores were recorded, and for analysis, the number of sites which showed presence or absence was calculated for each patient and they were categorized as <50% and equal to or more than 50%.

Statistical analysis

Data were analyzed using SPSS (Statistical package for social sciences.) version 15 IBM, USA. for windows. Case groups were compared first to the control group with regard to variables of interest using Chi-square tests (Pearson Chi-square continuity correction, Fisher's exact test) and the crudes odds ratio (OR) was estimated at 95% confidence limits; P < 0.05 was considered to be statistically significant. As control for the possible confounders, all variables with P < 0.05 were selected and entered into multivariate regression model; OR and 95% confidence limits were again estimated.


[Table 1] shows the distribution pattern of maternal periodontitis showed 59.4% of Group-4 had periodontitis and in Groups-1, 2, and 3, it was 54.8%, 52.2%, and 53.8%, respectively. [Table 2] depicts the comparison of variables between preterm normal birth weight group (Group-2) and control group (Group-1). None of the periodontal parameters showed any significant risk for preterm birth, but on severity basis, negative association was found with moderate (OR-0.332) and severe (OR - 0.254) periodontitis for preterm delivery. [Table 3] shows that the presence of periodontitis, bleeding score, and plaque score did not show any statistically significant association with PTLBW group. For normal term low birth weight group, the presence of periodontitis showed mild risk and was statistically significant after adjusting for potential confounders [Table 4].{Table 1}{Table 2}{Table 3}{Table 4}


This large cross-sectional study has contemplated the association between periodontitis and preterm birth while including all the main risk factors for preterm birth. In the present study, we have selected 3500 mothers from both government and private hospitals, thereby subsuming a wide range of socioeconomic backgrounds. Only, mothers with singleton gestation were included in the study as it was well established in previous studies that multiple gestation has a significant relationship with PTLBW.[7]

Maternal age is a significant risk factor for PLBW,[8] but in our study, the nuance was comparatively less (OR - 1.143). This may be due to the exclusion of higher risk category (<18 and >35 years) from our sample. Educational status of the participants also evinced less risk and this result is in concurrence with prior studies.[7],[8] In this study, the fact that participants who were uneducated and of low socioeconomic status were at a risk of delivering normal term low birth weight infants (OR - 1.356, OR - 1.338) in accordance with the previous studies.[9] The history of LBW and infection during pregnancy cited thrice the risk of LBW delivery (OR - 3.211, OR - 3.771) and this finding is in concurrence with prior studies.[7] The direct comparison of results of Preterm normal birth weight group with the other study results could not be done as this group was not included in any of the previous studies.

Prevalence rates of periodontitis vary between 10% and 60% among adults depending on the diagnostic criteria used.[7] In our study, the prevalence of periodontitis was 54.8% in Group-1, 52.2% in Group-2, 53.8% in Group-3, and 59.4% in Group IV. Similar to our study, the prevalence of maternal periodontitis was about 55.5% and 44% in the PLBW group as promulgated by Davenport et al. and Marin et al., respectively. Offenbacher et al. in their study stated higher prevalence of periodontitis (94%) whereas in studies done by Miyasaki et al. and Noack et al., the prevalence rate was comparatively less (31% and 22).

Our results were not in accordance with many authors such as Offenbacher et al. and Bosnjak et al.[10] who reported that maternal periodontitis could increase the risk of PLBW delivery. The study results can be explained by the following reasons. First, their studies comprised patients below 18 years and above 35 years of age, which is the high-risk category. However, in our study, we have restricted our inclusion criteria between 18 and 35 years. Second, in studies reporting the association, the sample size was comparatively less, but in our study, we have used a large sample size.

Nabet et al.[11] in their study used a large sample size (cases - 1118, controls - 1094) and they could find an association between generalized periodontitis and preterm birth. Third, the difference in study findings among the different characteristics of study population. Positive association between periodontitis and pregnancy outcomes was reported by studies done in the United States (Offenbacher et al., Jeffcoat et al.), Chile (Lopez et al.), Thailand (Dasanayake et al.), and Hungary (Radnai et al.).[12] Other studies done in Britain (Davenport et al., Moore et al.), Germany (Noack et al.), Iceland (Holbrook et al.), and Brazil (Marin et al.) could not find any such association. Fourth, the inconsistency of findings in the related literature is due to lack of uniform criteria for definition and measurement of periodontal disease. Manau et al.[5] did secondary analysis of their data with 14 types of case definitions and measurements used by various authors and they could find significant association between periodontitis and pregnancy outcomes only in 6 case definitions and not in others. In our study, we have used definition adopted by Bassani et al.[6] which was one among the six definitions with which Manau et al.[5] could find significant association. Fifth, in developing countries like India, the average birth weight is only 2.8 kg in contrast to 3.29 kg in developed countries. Even though WHO has defined LBW neonate as any neonate weighing <2500 g, adoption of this standard will result in high incidence of LBW neonates in developing countries. In our study, we have included 2500 g as criteria for defining LBW in neonate, but the adoption of 2000 g as a dividing line may help to analyze association even more appropriately.

Among the groups, in the normal term low birth weight group (Group-4), the presence of periodontitis showed a mild significant risk (crude OR - 1.206) (P = 0.032) similar to Bassani et al.[6] On the basis of severity, mild cases showed minimal risk for normal term LBW (crude OR - 1.561) but the ratio became annulled while adjusting for confounders and was not significant (adjusted OR - 1.341) similar to study done by Moliterano et al. The present study could not find any significant association between periodontal disease and pregnancy outcomes but crude association was found for LBW births. It has been suggested that the effect of periodontal disease on low birth weight could result from the stimulation of prostaglandin synthesis in the human amnion by inflamed gingival tissues or through the effect of endotoxin derived from periodontal infection.[13] The mechanisms through which periodontal disease could cause LBW remain biological, perhaps in the presence of specific genetic and environmental factors.

Periodontal disease shares many common risk factors with PLBW such as smoking, age, low socio economic status, and systemic health. In our study, in spite of having higher prevalence, periodontitis could not show any risk for adverse pregnancy outcomes, but concomitant factors and obstetric factors account for the prevalence of PLBW to a greater extent than periodontitis.


Periodontitis is not a significant independent risk factor but with higher prevalence rate and obstetric factors contributes a major risk for preterm and/or low birth weight babies. It would be more appropriate to carry out future longitudinal studies to clarify the issue.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


1Michalowicz BS, Durand R. Maternal periodontal disease and spontaneous preterm birth. Periodontol 2000 2007;44:103-12.
2Guimarães AN, Silva-Mato A, Miranda Cota LO, Siqueira FM, Costa FO. Maternal periodontal disease and preterm or extreme preterm birth: An ordinal logistic regression analysis. J Periodontol 2010;81:350-8.
3Kim J, Amar S. Periodontal disease and systemic conditions: A bidirectional relationship. Odontology 2006;94:10-21.
4Xiong X, Buekens P, Fraser WD, Beck J, Offenbacher S. Periodontal disease and adverse pregnancy outcomes: A systematic review. BJOG 2006;113:135-43.
5Manau C, Echeverria A, Agueda A, Guerrero A, Echeverria JJ. Periodontal disease definition may determine the association between periodontitis and pregnancy outcomes. J Clin Periodontol 2008;35:385-97.
6Bassani DG, Olinto MT, Kreiger N. Periodontal disease and perinatal outcomes: A case-control study. J Clin Periodontol 2007;34:31-9.
7Siqueira FM, Cota LO, Costa JE, Haddad JP, Lana AM, Costa FO. Intrauterine growth restriction, low birth weight, and preterm birth: Adverse pregnancy outcomes and their association with maternal periodontitis. J Periodontol 2007;78:2266-76.
8Offenbacher S, Boggess KA, Murtha AP, Jared HL, Lieff S, McKaig RG, et al. Progressive periodontal disease and risk of very preterm delivery. Obstet Gynecol 2006;107:29-36.
9Mathew RJ, Bose A, Prasad JH, Muliyil JP, Singh D. Maternal periodontal disease as a significant risk factor for low birth weight in pregnant women attending a secondary care hospital in South India: A case-control study. Indian J Dent Res 2014;25:742-7.
10Bosnjak A, Relja T, Vucićević-Boras V, Plasaj H, Plancak D. Pre-term delivery and periodontal disease: A case-control study from Croatia. J Clin Periodontol 2006;33:710-6.
11Nabet C, Lelong N, Colombier ML, Sixou M, Musset AM, Goffinet F, et al. Maternal periodontitis and the causes of preterm birth: The case-control Epipap study. J Clin Periodontol 2010;37:37-45.
12Radnai M, Gorzó I, Urbán E, Eller J, Novák T, Pál A. Possible association between mother's periodontal status and preterm delivery. J Clin Periodontol 2006;33:791-6.
13Klebanoff M, Searle K. The role of inflammation in preterm birth – Focus on periodontitis. BJOG 2006;113 Suppl 3:43-5.