Maternal periodontal disease and spontaneous preterm birth

Khat chewing in pregnant women associated with prelabor rupture of membranes, evidence from eastern Ethiopia

Introduction

Prelabor rupture of membranes (PROM) is a major factor that affects pregnancy outcome. Results from previous studies have suggested that there is an association between pregnant women, khat chewing and preterm birth, but evidence of association with PROM is sparse. This study therefore aims at identifying association between khat chewing in pregnancy and premature rupture of membranes in eastern Ethiopia.

Methods

A health facility-based cross-sectional study was conducted among 1688 pregnant women who came for delivery service in Harar town, Eastern Ethiopia between June to October in 2016. Data were collected using a pre-tested structured questionnaire and checklist to extract data from the medical record. The association between khat and PROM was examined using logistic regression analysis. A statistical significance was declared at p-value < 0.05.

Results

Of the 1688 pregnant women who participated in the study, 397 had prelabor rupture of the membranes, representing a proportion of 23.5% [(95% CI: (21.5, 25.6%)]. Of these 397 prelabor rupture of the membranes 198 (31.53%) were from Khat chewing mothers and, 199(18.77%) were from non-khat chewing mothers. After controlling for potential confounders, the multivariable logistic regression analysis revealed the odds of PROM was 1.51 times higher among khat chewed pregnant women [AOR = 1.51; 95% CI; (1.11, 2.07)] were had no khat chewing.

Conclusion

This study found a significant association between khat chewing in pregnancy and PROM. Efforts to reduce PROM need to consider prevention of khat chewing in pregnancy. A specific strategy need to protect pregnant women from khat chewing.

A review of the influence of periodontal treatment in systemic diseases

The effects and consequences of periodontal diseases might not be confined to the oral cavity. A great body of evidence has arisen supporting the claim demonstrating an association with several systemic conditions and diseases. With different levels of evidence, an association between periodontal disease and cardiovascular disease, diabetes, psoriasis, rheumatoid arthritis, pregnancy outcomes and respiratory diseases has been established. However, the true nature of this association, if it is causal, still remains elusive. For a better understanding of the complex relationships linking different conditions, interventional studies now begin to focus on the possible outcomes of periodontal treatment in relation to the events, symptoms and biomarkers of several systemic disorders, assessing if periodontal treatment has any impact on them, hopefully reducing their severity or prevalence. Therefore, we proceeded to review the recent literature on the subject, attempting to present a brief explanation of the systemic condition or disease, what proposed mechanisms might give biological plausibility to its association with periodontal disease, and finally and more importantly, what data are currently available pertaining to the effects periodontal treatment may have. Raising awareness and discussing the possible benefits of periodontal treatment on overall systemic health is important, in order to change the perception that periodontal diseases are only limited to the oral cavity, and ultimately providing better and comprehensive care to patients.

Spontaneous preterm birth: advances toward the discovery of genetic predisposition

Evidence from family and twin-based studies provide strong support for a significant contribution of maternal and fetal genetics to the timing of parturition and spontaneous preterm birth. However, there has been only modest success in the discovery of genes predisposing to preterm birth, despite increasing sophistication of genetic and genomic technology. In contrast, DNA variants associated with other traits/diseases have been identified. For example, there is overwhelming evidence that suggests that the nature and intensity of an inflammatory response in adults and children are under genetic control. Because inflammation is often invoked as an etiologic factor in spontaneous preterm birth, the question of whether spontaneous preterm birth has a genetic predisposition in the case of pathologic inflammation has been of long-standing interest to investigators. Here, we review various genetic approaches used for the discovery of preterm birth genetic variants in the context of inflammation-associated spontaneous preterm birth. Candidate gene studies have sought genetic variants that regulate inflammation in the mother and fetus; however, the promising findings have often not been replicated. Genome-wide association studies, an approach to the identification of chromosomal loci responsible for complex traits, have also not yielded compelling evidence for DNA variants predisposing to preterm birth. A recent genome-wide association study that included a large number of White women (>40,000) revealed that maternal loci contribute to preterm birth. Although none of these loci harbored genes directly related to innate immunity, the results were replicated. Another approach to identify DNA variants predisposing to preterm birth is whole exome sequencing, which examines the DNA sequence of protein-coding regions of the genome. A recent whole exome sequencing study identified rare mutations in genes encoding for proteins involved in the negative regulation (dampening) of the innate immune response (eg, CARD6, CARD8, NLRP10, NLRP12, NOD2, TLR10) and antimicrobial peptide/proteins (eg, DEFB1, MBL2). These findings support the concept that preterm labor, at least in part, has an inflammatory etiology, which can be induced by pathogens (ie, intraamniotic infection) or "danger signals" (alarmins) released during cellular stress or necrosis (ie, sterile intraamniotic inflammation). These findings support the notion that preterm birth has a polygenic basis that involves rare mutations or damaging variants in multiple genes involved in innate immunity and host defense mechanisms against microbes and their noxious products. An overlap among the whole exome sequencing-identified genes and other inflammatory conditions associated with preterm birth, such as periodontal disease and inflammatory bowel disease, was observed, which suggests a shared genetic substrate for these conditions. We propose that whole exome sequencing, as well as whole genome sequencing, is the most promising approach for the identification of functionally significant genetic variants responsible for spontaneous preterm birth, at least in the context of pathologic inflammation. The identification of genes that contribute to preterm birth by whole exome sequencing, or whole genome sequencing, promises to yield valuable population-specific biomarkers to identify the risk for spontaneous preterm birth and potential strategies to mitigate such a risk.

Knowledge, awareness, and practice among gynecologists, medical practitioners and dentists in Madurai regarding association between periodontitis and pregnancy outcomes

Background:

The prevalence of oral disease during pregnancy affects the health of the fetus and mother. The interdisciplinary protocol between general dentists (GDs), gynecologists, and general medical practitioners (GMPs) is proved to reduce the incidence of maternal and neonatal complications.

Aim:

The aim of the present survey is to assess the knowledge, awareness, and attitude of practicing gynecologists, GMPs, and GDs regarding the association of periodontitis and adverse pregnancy outcomes.

Materials and Methods:

This cross-sectional study was conducted among 150 health-care professionals in Madurai. A well-structured pretested questionnaire consisted of 12 questions which were used to assess the awareness of association regarding maintaining oral health during pregnancy among GMPs, GDs, and gynecologists. The knowledge, awareness, and practice scores were calculated for the correct answers to the questions. A software program (SPSS 12) was used for statistical analysis.

Results:

The mean age of participants was of 33.14 ± 1.5, 32.58 ± 2.80, and 37.7 ± 9.7, respectively. Majority of the participants agreed the importance of dental examination and maintaining oral health during pregnancy GMPs (96%), GDs (100%), and gynecologists (92%). About 92% of gynecologists and GMPs supported that providing dental treatment during pregnancy improved pregnancy outcomes. About 64%, 76%, and 68% of GMPs, GDs, and gynecologists, respectively, confirmed the association between periodontal disease and adverse pregnancy outcomes.

Conclusion:

In this study, knowledge and awareness of gynecologists and GMPs are appreciable; however, their attitude toward bringing the facts into clinical practice needs to be improved through integrated programs.

Maternal Risk Factors and Periodontal Disease: A Cross-sectional Study among Postpartum Mothers in 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.

Periodontal disease and intra-amniotic complications in women with preterm prelabor rupture of membranes

OBJECTIVE

Periodontal disease is frequently suggested as a possible causal factor for preterm delivery. The link between periodontal disease and preterm delivery is a possible translocation of periopathogenic bacteria to the placenta and amniotic fluid as well as a systemic response to this chronic inflammatory disease. However, there is a lack of information on whether there is an association between clinical periodontal status in women with preterm prelabor rupture of membranes (PPROM) and the presence of microbial invasion of the amniotic cavity (MIAC) and intra-amniotic inflammation (IAI). Therefore, the main aim of this study was to evaluate the incidence and severity of periodontal disease in women with PPROM. The secondary aim was to characterize an association between periodontal status and the presence of intra-amniotic PPROM complications (MIAC and/or IAI).

MATERIALS AND METHODS

Seventy-eight women with PPROM at gestational ages between 24 + 0 and 36 + 6 weeks were included in this study. The samples of amniotic fluid were obtained at admission via transabdominal amniocentesis, and amniotic fluid interleukin (IL)-6 concentrations were determined using a point-of-care test. All women had a full-mouth recording to determine the periodontal and oral hygiene status. Probing pocket depth and clinical attachment loss were measured at four sites on each fully erupted tooth.

RESULTS

In total, 45% (35/78) of women with PPROM had periodontal disease. Mild, moderate, and severe periodontal disease was present in 19% (15/78), 19% (15/78), and 6% (5/78) of women, respectively. The presence of MIAC and IAI was found in 28% (22/78) and 26% (20/78) of women, respectively. Periopathogenic bacteria (2 × Streptococcus intermedius and 1 × Fusobacterium nucleatum) was found in the amniotic fluid of 4% (3/78) of women. There were no differences in periodontal status between women with MIAC and/or IAI and women without these intra-amniotic complications.

CONCLUSIONS

The presence of MIAC and IAI was not related to the periodontal status of women with PPROM.

Toll-Like Receptors: A Key Marker for Periodontal Disease and Preterm Birth - A Contemporary Review

The receptors of the innate immune system have evolved to recognize pathogenic bacteria in a complex manner. Out of these immune receptors, the pattern recognition receptors (PRRs) such as Toll like receptors have gained importance off late to play a key role in the activation of cascade of inflammatory cytokines in pathogenesis of preterm birth. Preterm birth has become leading cause of neonatal deaths globally. The concept of oral infection influencing the occurrence of preterm delivery has gained importance. Translocation of periodontal pathogens and inflammatory mediators play role in the pathogenesis of preterm labour. The transmembrane toll like receptors of innate immunity have been recently implicated in the association of periodontal infection and preterm labour. The TLRs are considered as a key marker and TLR blockade can be a critical method for treating women who are exposed to periodontal pathogens. This review is aimed at discussing the role of TLR in periodontal disease and its relationship with preterm birth.

The Two-Way Association of Periodontal Infection with Systemic Disorders: An Overview

Oral cavity that harbors diverse bacterial populations could also act as a site of origin for spread of pathogenic microorganisms to different body sites, particularly in immunocompromised hosts, patients, the elderly, or the underprivileged. A number of recent publications have advocated that patients with periodontal diseases are more susceptible to metabolic endotoxemia, inflammation, obesity, type 2 diabetes, and other related systemic complications, concluding that periodontal diseases could be a potential contributing risk factor for a wide array of clinically important systemic diseases. However, despite a significant increase in the prevalence of periodontal infections and systemic diseases in the past few decades, the fundamental biological mechanisms of connection between these ailments are still not fully explicated. Consequently, the mechanisms by which this bidirectional damage occurs are being explored with a concentric vision to develop strategies that could prevent or control the complications of these ailments. This paper attempts to summarize and hypothesize the diverse mechanisms that hint to a certain connection between the two prevalent chronic situations.

Evaluation of the knowledge of pregnant women about the relationship between oral diseases and pregnancy complications

INTRODUCTION: Chronic persistent low-level infection in pregnant women, such as periodontal disease (PD) may impair maternal-fetal unit, since the infectious process induces the release of chemical mediators involved in the process of prematurity. OBJECTIVE: To assess the knowledge of mothers as regards the relationship between oral diseases and pregnancy complications. METHOD: A cross-sectional epidemiological study was conducted with 104 pregnant women indexed in the Primary Care Information System (SIAB), in the Family Health Strategies (FHS), using a structured questionnaire. Data were recorded in SPSS and analyzed using descriptive and inferential statistics, considering a significance level of 5%. RESULT: Most patients (64.4%) were domestic workers, (48.1%) aged 24 to 34 years, (55.8%) showed complete the 2nd grade and incomplete high school education, and (49%) were primiparous. Among the participants, 76% were unaware of the relationship between oral disease, prematurity and giving birth to low birth weight babies. Statistically significant association was found between: educational level and knowledge about prenatal dental care (p = 0.012); since it was shown that 90.4% ignored the existence of this activity and 65.4% had never received information about the care of baby's oral hygiene (p = 0.003). CONCLUSION: Most women were unaware of the relationship of PD with prematurity, and showed lack of information about the care of mother and baby oral hygiene, highlighting the need for greater integration between the dental surgeon and other primary care professionals to promote oral health care of pregnant women and reduce the ratio of PD with pregnancy complications.

The effect of phase-I periodontal therapy on pregnancy outcome in chronic periodontitis patients

Recent studies have shown periodontal diseases (gum diseases) as risk factors for adverse pregnancy outcomes, such as prematurity and low birth weight. Objectives of the present study were to determine the effect of non-surgical periodontal therapy on pregnancy outcomes in women with periodontitis and to detect IgM and IgG status in cord blood during delivery. A total of 20 pregnant women in their 2nd trimester and associated with chronic generalised periodontitis were selected and recruited for the study. They were grouped into two: Group 1 (treatment group) and Group 2 (control). Periodontal parameters of all the subjects were recorded at baseline and after delivery. Data related to weight of the infant and type of delivery was recorded. During the delivery, cord blood was collected for the estimation of IgM and IgG antibodies. All the recordings were subjected for statistical analysis. The study concluded that maternal periodontitis was associated with adverse pregnancy outcomes.

Bi-directional relationship between pregnancy and periodontal disease

During pregnancy profound perturbations in innate and adaptive immunity impact the clinical course of a number of infectious diseases, including those affecting periodontal tissues. Conversely, it has been suggested that periodontal infections may increase the risk of adverse pregnancy outcomes. In this review, a summary of the literature associated with the bidirectional relationship between pregnancy and periodontal disease as well as the possible mechanisms behind this interaction were examined.

Periodontal disease and systemic complications

Periodontal diseases comprise a number of infectious and inflammatory conditions brought about by the interaction between supragingival and subgingival biofilms and the host inflammatory response. Periodontal diseases should be considered systemic conditions. This means that they are both modulated by the body's systems and play a role as a risk factor for systemic derangements. The current evidence supports some of these interactions, such as smoking as a risk factor for periodontal disease and diabetes mellitus, as both influenced by and influencing inflammatory changes in the periodontal tissue. Other potential associations are still being researched, such as obesity, hormonal changes, cardiovascular disease, and adverse outcomes in pregnancy. These, and others, still require further investigation before the repercussions of periodontal disease can be fully elucidated. Nevertheless, at the present time, the treatment of periodontal diseases-and, most importantly, their prevention-enables adequate intervention as a means of ensuring periodontal health.

Intrapregnancy non-surgical periodontal treatment and pregnancy outcome: a randomized controlled trial

BACKGROUND

The purpose of the present study is to investigate the potential link between maternal periodontitis and pregnancy outcomes, including preterm birth (<37 weeks) and low birth weight (<2,500 g).

METHODS

Ninety nine pregnant females with mild/moderate periodontitis were randomly allocated to a control (n = 50) or test (n = 49) group. Test group participants received intrapregnancy non-surgical periodontal treatment, whereas this was deferred until after delivery for controls. Demographic and baseline clinical data were obtained for all participants at initial assessment pretreatment. Clinical data were rerecorded for test participants at review 8 weeks after treatment. Birth outcomes were completed at delivery by midwives who also collected cord blood samples when possible; the latter were analyzed to determine the presence/levels of cytokines interleukin (IL)-1β, IL-6, and IL-8. All data were analyzed on an intention-to-treat basis using appropriate statistical tests.

RESULTS

Random allocation of participants resulted in well-balanced control and test groups. All test group participants and all but one control participant gave birth to a live infant. No significant differences were detected between control and test groups with regard to birth outcome measures of birth weight and gestational age or in relation to cytokine prevalence/levels.

CONCLUSION

Intrapregnancy non-surgical periodontal treatment, completed at 20 to 24 weeks, did not reduce the risk of preterm, low-birth-weight delivery in this population.

Pathogenic mechanisms linking periodontal diseases with adverse pregnancy outcomes

In the last 2 decades, a large proportion of studies have focused on the relationship between maternal periodontal disease and poor obstetric outcomes. The aim of the present review is to summarize the current knowledge about human studies on the pathogenetic mechanisms linking periodontal diseases with adverse pregnancy outcomes. A search of the medical literature was conducted using NIH (National Institute of Health) Pubmed through April 2011. Articles were identified with the Medical Subject Heading (MeSH) and free text terms "small for gestational age (SGA)," "preeclampsia," "preterm labor," and "periodontal disease." Experimental human studies have shown that periodontal pathogens may disseminate toward placental and fetal tissues accompanied by an increase in inflammatory mediators in the placenta. As such, new inflammatory reactions within the placental tissues of the pregnant woman may occur, the physiological levels of prostaglandin E(2) (PGE(2)) and tumor necrosis factor-α (TNF-α) in the amniotic fluid may increase and eventually lead to premature delivery. Although many data from clinical trials suggest that periodontal disease may increase the adverse pregnancy outcome, the exact pathogenetic mechanism involved remains controversial. The findings explain the potential link between periodontal infections and adverse pregnancy outcomes. First, periodontal bacteria can directly cause infections both of the uteroplacenta and the fetus; second, systemic inflammatory changes induced by periodontal diseases can activate responses at the maternal-fetal interface. Of note, associative studies have produced different results in different population groups and no conclusive evidence has still been produced for the potential role of preventive periodontal care to reduce the risk factors of preterm birth.

Periodontal treatment during pregnancy decreases the rate of adverse pregnancy outcome: a controlled clinical trial

Objectives

The aim of this study was to evaluate the effects of non-surgical treatment of periodontal disease during the second trimester of gestation on adverse pregnancy outcomes.

Material and Methods

Pregnant patients during the 1^st and 2^nd trimesters at antenatal care in a Public Health Center were divided into 2 groups: NIG – "no intervention" (n=17) or IG- "intervention" (n=16). IG patients were submitted to a non-surgical periodontal treatment performed by a single periodontist consisting of scaling and root planning (SRP), professional prophylaxis (PROPH) and oral hygiene instruction (OHI). NIG received PROPH and OHI during pregnancy and were referred for treatment after delivery. Periodontal evaluation was performed by a single trained examiner, blinded to periodontal treatment, according to probing depth (PD), clinical attachment level (CAL), plaque index (PI) and sulcular bleeding index (SBI) at baseline and 35 gestational weeks-28 days post-partum. Primary adverse pregnancy outcomes were preterm birth (<37 weeks), low birth weight (<2.5 kg), late abortion (14-24 weeks) or abortion (<14 weeks). The results obtained were statistically evaluated according to OR, unpaired t test and paired t test at 5% significance level.

Results

No significant differences were observed between groups at baseline examination. Periodontal treatment resulted in stabilization of CAL and PI (p>0.05) at IG and worsening of all periodontal parameters at NIG (p<0.0001), except for PI. Significant differences in periodontal conditions of IG and NIG were observed at 2nd examination (p<0.001). The rate of adverse pregnancy outcomes was 47.05% in NIG and 6.25% in IG. Periodontal treatment during pregnancy was associated to a decreased risk of developing adverse pregnancy outcomes [OR=13.50; CI: 1.47-123.45; p=0.02].

Conclusions

Periodontal treatment during the second trimester of gestation contributes to decrease adverse pregnancy outcomes.

Birth weight of infants of mothers with aggressive periodontitis

BACKGROUND

It was hypothesized that if periodontal infections predispose low birth weights and premature birth, then such outcomes should be apparent when the mother has aggressive periodontitis (AgP).

METHODS

Birth weight data were collected by questionnaire from females with AgP, their periodontally healthy siblings, and unrelated periodontally healthy women. Both prospective and retrospective birth outcome data were used. Because many of the periodontal evaluations were performed after the births, there were incomplete data regarding most of the risk factors for low birth weight. We determined associations between mothers' periodontal diagnoses and clinical variables and the reported birth weights.

RESULTS

There were no significant differences in mean birth weights of babies born to control subjects or AgP patients. This was true whether all the births were considered or only those reported <1 or 2 years before periodontal examination. For periodontally healthy controls, 13.2% of babies born to siblings of AgP patients and 12.8% of babies born to unrelated mothers weighed <2,500 g, whereas 9.9% of those born to mothers with generalized AgP and 10.3% of those born to mothers with localized AgP weighed <2,500 g.

CONCLUSIONS

Because of the relative rarity of AgP in the population, and attendant difficulties in performing a prospective study of its association with pregnancy outcomes, we used a compromised approach using prospective data as well as weaker retrospective data assuming that disease onset was likely before the births. Our results, within the limitations of this approach, indicate no evidence that AgP in the mother predisposes low birth weights. AgP has many unique biologic characteristics that differentiate it from chronic forms of periodontal disease, and the possible lack of its association with birth weight may be another such characteristic.

Human trophoblast responses to Porphyromonas gingivalis infection

Porphyromonas gingivalis is a periodontal pathogen that is also associated with preterm low-birthweight delivery. We investigated the transcriptional responses of human extravillous trophoblasts (HTR-8) to infection with P. gingivalis. Over 2000 genes were differentially regulated in HTR-8 cells by P. gingivalis. In ontology analyses of regulated genes, overpopulated biological pathways included mitogen-activated protein (MAP) kinase signaling and cytokine production. Immunoblots confirmed overexpression of the MAP kinase pathway components MEK3, p38 and Max. Furthermore, P. gingivalis infection induced phosphorylation and activation of MEK3 and p38. Increased production of interleukin (IL)-1beta and IL-8 by HTR-8 cells was demonstrated phenotypically by enzyme-linked immunosorbent assay of HTR-8 cell lysates and culture supernatants. Hence, infection of trophoblasts by P. gingivalis can impact signal transduction pathways and modulate cytokine expression, outcomes that could disrupt the maintenance of pregnancy.

DNA from Porphyromonas gingivalis and Tannerella forsythia induce cytokine production in human monocytic cell lines

Toll-like receptor 9 (TLR9) expression is increased in periodontally diseased tissues compared with healthy sites indicating a possible role of TLR9 and its ligand, bacterial DNA (bDNA), in periodontal disease pathology. Here, we determine the immunostimulatory effects of periodontal bDNA in human monocytic cells (THP-1). THP-1 cells were stimulated with DNA of two putative periodontal pathogens: Porphyromonas gingivalis and Tannerella forsythia. The role of TLR9 in periodontal bDNA-initiated cytokine production was determined either by blocking TLR9 signaling in THP-1 cells with chloroquine or by measuring IL-8 production and nuclear factor-kappaB (NF-kappaB) activation in HEK293 cells stably transfected with human TLR9. Cytokine production (IL-1beta, IL-6, and TNF-alpha) was increased significantly in bDNA-stimulated cells compared with controls. Chloroquine treatment of THP-1 cells decreased cytokine production, suggesting that TLR9-mediated signaling pathways are operant in the recognition of DNA from periodontal pathogens. Compared with native HEK293 cells, TLR9-transfected cells demonstrated significantly increased IL-8 production (P < 0.001) and NF-kappaB activation in response to bDNA, further confirming the role of TLR9 in periodontal bDNA recognition. The results of PCR arrays demonstrated upregulation of proinflammatory cytokine and NF-kappaB genes in response to periodontal bDNA in THP-1 cells, suggesting that cytokine induction is through NF-kappaB activation. Hence, immune responses triggered by periodontal bacterial nucleic acids may contribute to periodontal disease pathology by inducing proinflammatory cytokine production through the TLR9 signaling pathway.

Maternal periodontitis and the causes of preterm birth: the case-control Epipap study

AIM

To analyse the association between maternal periodontitis and preterm birth (<37 weeks' gestation) according to the causes of preterm birth.

MATERIALS AND METHODS

Epipap is a case-control multi-centre study of singleton livebirths. One thousand one hundred and eight women with preterm deliveries and 1094 with deliveries at term (> or =37 weeks) at six French maternity units were included. Periodontal examinations after delivery identified localized and generalized periodontitis. Cases were classified according to four causes of preterm birth. Polytomous logistic regression analysis was used to control for confounders (maternal age, parity, nationality, educational level, marital status, employment during pregnancy, body mass index before pregnancy, smoking status) and the examiner.

RESULTS

Localized periodontitis was identified in 129 (11.6%) cases and in 118 (10.8%) control women and generalized periodontitis in 148 (13.4%) and 118 (10.8%), respectively. A significant association was observed between generalized periodontitis and induced preterm birth for pre-eclampsia [adjusted odds ratio 2.46 [95% confidence intervals (95% CI)1.58-3.83]. Periodontitis was not associated with spontaneous preterm birth or preterm premature rupture of membranes or with the other causes.

CONCLUSION

Maternal periodontitis is associated with an increased risk of induced preterm birth due to pre-eclampsia.

Porphyromonas gingivalis invades human trophoblasts and inhibits proliferation by inducing G1 arrest and apoptosis

Porphyromonas gingivalis is an oral pathogen that is also associated with serious systemic conditions such as preterm delivery. Here we investigated the interaction between P. gingivalis and a cell line of extravillous trophoblasts (HTR-8) derived from the human placenta. P. gingivalis internalized within HTR-8 cells and inhibited proliferation through induction of arrest in the G1 phase of the cell cycle. G1 arrest was associated with decreased expression of cyclin D and of CDKs 2, 4 and 6. In addition, levels of CDK inhibitors p15, p16, p18 and p21 were increased following P. gingivalis infection. The amount of Rb was diminished by P. gingivalis, and transient overexpression of Rb, with concomitant upregulation of phospho-Rb, relieved P. gingivalis-induced G1 arrest. HTR-8 cells halted in the G1 phase became apoptotic, and apoptosis was accompanied by an increase in the ratio of Bax/Bcl-2 and increased activity of caspases 3, 7 and 9. HTR-8 cells infected with P. gingivalis also exhibited a sustained activation of ERK1/2, and knock-down of ERK1/2 activity with siRNA abrogated both G1 arrest and apoptosis. Thus, P. gingivalis can invade placental trophoblasts and induce G1 arrest and apoptosis through pathways involving ERK1/2 and its downstream effectors, properties that provide a mechanistic basis for pathogenicity in complications of pregnancy.

Change in periodontitis during pregnancy and the risk of pre-term birth and low birthweight

AIM

Determine whether periodontitis progression during pregnancy is associated with adverse birth outcomes.

METHODS

We used clinical data and birth outcomes from the Obstetrics and Periodontal Therapy Study, in which randomly selected women received periodontal treatment before 21 weeks of gestation (N=413) or after delivery (410). Birth outcomes were available for 812 women and follow-up periodontal data for 722, including 75 whose pregnancies ended <37 weeks. Periodontitis progression was defined as >or=3 mm loss of clinical attachment. Birth outcomes were compared between non-progressing and progressing groups using the log rank and t tests, separately in all women and in untreated controls.

RESULTS

The distribution of gestational age at the end of pregnancy (p>0.1) and mean birthweight (3295 versus 3184 g, p=0.11) did not differ significantly between women with and without disease progression. Gestational age and birthweight were not associated with change from baseline in percentage of tooth sites with bleeding on probing or between those who did versus did not progress according to a published definition of disease progression (p>0.05).

CONCLUSIONS

In these women with periodontitis and within this study's limitations, disease progression was not associated with an increased risk for delivering a pre-term or a low birthweight infant.

Periodontal disease as a risk factor for adverse pregnancy outcomes: a prospective cohort study

AIM

The aim of this study was to determine the association between periodontitis and the incidence of preterm birth (PB), low birth weight (LBW) and preterm low birth weight (PLBW) MATERIAL AND METHODS: One thousand and ninety-six women were enrolled. Periodontal data, pregnancy outcome variables and information on other factors that may influence adverse pregnancy outcomes were collected. Data were analysed using a logistic regression model.

RESULTS

The incidence of PB and LBW was 6.6% and 6.0%, respectively. The incidence of PLBW was 3.3%. PB was related to mother's age, systemic diseases, onset of prenatal care, previous PBs, complications of pregnancy, type of delivery, the presence of untreated caries and the presence of periodontitis (odds ratio 1.77, 95% confidence interval: 1.08-2.88). LBW was related to mother's smoking habits, ethnicity, systemic diseases, previous LBW babies, complications of pregnancy and type of delivery. PLBW was related to mother's age, onset of prenatal care, systemic diseases, previous LBW babies, complications of pregnancy and type of delivery.

CONCLUSIONS

The factors involved in many cases of adverse pregnancy outcomes have still not being identified, although systemic infections may play a role. This study found a modest association between periodontitis and PB. Further research is required to establish whether periodontitis is a risk factor for PB and/or LBW.