Preterm premature rupture of membranes (P-PROM) is clinically defined as the rupture of fetal membranes before the completion of the 37th gestational week, and it represents a significant concern in obstetrics due to its association with maternal morbidity¹, neonatal mortality, and preterm labor, especially in developing countries where access to advanced perinatal care may be limited.² Although the incidence of P-PROM has been reported in only 2–5% of all pregnancies, its clinical impact is disproportionately large because it accounts for approximately 25–30% of all preterm deliveries.³ Preterm deliveries themselves have been recognized as a major contributor to neonatal mortality worldwide, but beyond mortality, they are linked to a wide spectrum of morbidities including respiratory distress syndrome, immunologic dysfunctions, feeding difficulties, developmental delays, and long-term neurological deficits^4,5,6. The pathophysiology underlying P-PROM remains incompletely elucidated; however, it is widely accepted that the process is multifactorial⁷. Current evidence highlights intrauterine infection and inflammation as central mechanisms that compromise membrane integrity, weaken collagen structures, and increase the likelihood of premature rupture. Among the potential extrauterine sources of maternal inflammation, the role of periodontal disease has gained increasing attention. Periodontal disease is a chronic inflammatory condition affecting the supporting tissues of the teeth and is primarily associated with dental plaque biofilm colonized by gram-negative anaerobic microorganisms.^8,9 This condition leads to gingival inflammation, destruction of periodontal ligament, and alveolar bone resorption, which if left untreated, may serve as a systemic source of inflammatory mediators¹⁰.  The translocation of oral pathogens and their by-products into maternal blood can amplify systemic inflammation, a factor suspected of contributing to adverse pregnancy outcomes including P-PROM. During pregnancy, complete blood count (CBC) analysis provides an accessible and cost-effective tool to assess systemic health, and specific parameters derived from CBC, such as the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and mean platelet volume (MPV), have emerged as reliable markers of systemic inflammation and immune response activity. Elevated values of these markers have been linked with inflammatory conditions in both general and obstetric populations^11,12. Several epidemiological and clinical studies suggest an association between maternal periodontitis and adverse pregnancy outcomes such as preterm birth, low birth weight, and preeclampsia, lending further support to the notion that poor oral health may be a modifiable risk factor for obstetric complications¹³. However, despite accumulating evidence, the relationship between maternal oral and dental health and pregnancy complications like P-PROM remains controversial and inconsistently reported in the literature, with some studies demonstrating significant associations while others fail to confirm such links¹⁴. It has been hypothesized that bacteremia resulting from periodontal pathogens or carious lesions could stimulate maternal immune activation and inflammatory cascades, thereby weakening fetal membranes.

AIM

The relationships of inflammatory blood markers with maternal periodontal and dental states and their effects on preterm membrane rupture development.

This was a prospective case–control study carried out in thedepartment of dentistry over a period 1 year. A total of 90 pregnant women between 24 and 36 weeks of gestation were included in the study. Of these, 35 women with confirmed preterm premature rupture of membranes (PPROM) formed the case group, while 55 women with normal pregnancies without PPROM were enrolled as controls. Women aged 18 and onwards who provided informed consent were included. Exclusion criteria were  chronic systemic illnesses such as diabetes mellitus, hypertension, or renal disease, history of autoimmune or inflammatory disorders, prior long-term antibiotic or immunosuppressive use, and women with a history of smoking, alcohol, or substance abuse.Clinical and demographic details such as maternal age, parity, gestational age, and BMI were recorded. All participants underwent a detailed dental and periodontal examination performed by a trained dentist. Standardized oral health indices were used, including Plaque Index (PI), Gingival Index (GI), Clinical Attachment Loss (CAL), Periodontal Depth (PD), and the Decayed, Missing, Filled Teeth (DMFT) index.Venous blood samples were collected at admission and analyzed for complete blood count parameters. Inflammatory markers were derived from these counts, including total leukocyte count, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), mean platelet volume (MPV), plateletcrit (PCT), and C-reactive protein (CRP).

Table 1: Maternal age distribution

In the PROM group, most participants were aged 18–30 years (26.3%), followed by equal proportions below 18 years (26.3%) and above 30 years (47.3%).Similarly, in the control group, the majority were 18–30 years (42.3%), with 26.9% below 18 years and 30.8% above 30 years.

Table 2: Parity distribution

In the PROM group, 42.1% were primigravida and 57.9% were multigravida.

Similarly, in the control group, 48.1% were primigravida and 51.9% were multigravida, showing a nearly balanced distribution in both groups.

Table 3: Gestational age

In the PROM group, more than half of the women (52.6%) were between 32–34 weeks of gestation, followed by 26.3% above 34 weeks and 21.1% below 32 weeks.In contrast, the control group had a majority above 34 weeks (57.7%), with 34.6% between 32–34 weeks and only 7.7% below 32 weeks.

Table 4: Oral Hygiene Habits of Study Participants

In the PROM group, most women brushed once daily (42.1%), followed by 36.8% who brushed seldom and 21.1% who brushed twice daily, while in the control group, 42.3% brushed once daily, 30.8% seldom, and 26.9% twice daily.

Regarding other oral hygiene practices, 15.8% of PROM cases and 5.8% of controls reported additional habits, whereas the majority in both groups did not practice any.

Table 5:Blood counts of subjects and relationship between PPROM

In the PROM group, leukocyte count, NLR, PLR, and PCT were slightly higher compared to the control group, indicating increased inflammatory activity.

In contrast, MPV and MPV/PLT ratio were marginally lower in PROM, while MLO values were almost identical in both groups.

Table  6:  Oral indices of subjects and relationship between PPROM

Oral health indices were higher in the PROM group, with greater DMFT, plaque index, gingival index, and periodontal depth compared to controls.

Clinical attachment loss also showed wider variation in PROM, indicating more severe periodontal involvement.

Table 7:Spearman Correlation Coefficients (ρ) Between Blood Count Parameters and Oral Health Indices

Leukocyte count, NLR, PLR, and PCT showed positive correlations with oral indices, strongest for periodontal depth and gingival index, indicating their link with inflammation.

In contrast, MPV and MPV/PLT ratio demonstrated weak negative correlations, while MLO showed only minimal positive association with oral parameters.

The age distribution of participants in both PROM and control groups showed a similar pattern. In the PROM group, the largest proportion of patients were between 18–30 years, accounting for 26.3% of cases. The remaining patients were  distributed, with 26.3% and 47.4%  in the <18 years and >30 years categories. In the control group, the majority were also in the 18–30 years range, representing 42.3% of cases. Participants aged <18 years contributed 26.9%, while those above 30 years accounted for 30.8%. Overall, both groups demonstrated a predominance of patients in the 18–30 years age group, indicating that PROM was more frequent in this reproductive age bracket.Similarly, Esercan A, Demir I¹⁵ showed the he mean maternal age in PPROM and control groups was 30.17±7.24 and 24.47±4.05 years, respectively. Maternal age in the PPROM group was greater than the control group and the difference was statistically significant (p: 0.01).

In the present study, the parity status of women was assessed in both PROM and control groups. In the PROM group, 42.1% of cases were primigravida, while the majority, 57.9%, were multigravida. This indicates that PROM occurred more frequently among multigravida women. In comparison, the control group showed 48.1% primigravida and 51.9% multigravida, suggesting a more balanced distribution. Although both groups included a considerable proportion of primigravida women, multigravida status was slightly higher in the PROM group. Overall, the findings suggest that multiparity may be a contributing factor associated with PROM.

The distribution of gestational age showed notable differences between the PROM and control groups. In the PROM group, the majority of women (52.6%) presented between 32–34 weeks of gestation. A smaller proportion, 26.3%, were above 34 weeks, while 21.1% were below 32 weeks. In contrast, the control group had most participants (57.7%) in the >34 weeks category. About 34.6% of the control group fell between 32–34 weeks, and only 7.7% were below 32 weeks. Overall, PROM was more common at an earlier gestational age, whereas controls were predominantly in the later gestational weeks.Temur, I., Temur, K.T., Donertas, S.N. et al.¹⁶ showed gestational week was significantly shorter in the P-PROM group compared to the control group, under < 37 weeks (p < 0.05). The range of gestational weeks in the P-PROM group was 33–36 weeks, whereas the range in the control group was 37–41 weeks.

The brushing frequency pattern was comparable between the PROM and control groups with some variations. In the PROM group, the highest proportion of women (42.1%) reported brushing once daily. This was followed by 36.8% who brushed seldom and only 21.1% who brushed twice daily. In the control group, a similar trend was noted with 42.3% brushing once daily, 30.8% seldom, and 26.9% twice daily. Analysis of other oral hygiene habits showed that 15.8% of PROM cases practiced additional methods such as mouth rinsing or tongue cleaning compared to only 5.8% in controls. The majority of participants, however, did not follow any other oral hygiene practices, with 84.2% in the PROM group and 94.2% in the control group reporting no additional measures.

The hematological profile showed distinct differences between the PROM and control groups. The leukocyte count was higher in the PROM group, with a median of 11,300/µL compared to 9,500/µL in controls. Similarly, inflammatory markers such as NLR and PLR were elevated in PROM cases, suggesting a stronger systemic inflammatory response. PCT values were also marginally higher in PROM than in the control group. On the other hand, platelet indices such as MPV and MPV/PLT ratio were slightly lower among PROM patients. Interestingly, MLO values remained nearly the same in both groups, indicating no significant variation. Overall, these findings highlight a trend toward heightened inflammation in PROM cases compared to controls.  the mean of the total PPROM group’s NLR values was statistically different than the control group (both p <0.001). PLR values in the PPROM group at 25-30 gestational weeks were significantly higher than in the control group (p: 0.03).

The assessment of oral indices revealed poorer oral health status among women in the PROM group compared to controls. The DMFT score was higher in PROM cases, reflecting a greater burden of dental caries. Plaque index and gingival index values were also markedly elevated, indicating increased plaque accumulation and gingival inflammation. Periodontal depth was significantly greater in the PROM group, suggesting more advanced periodontal involvement. Clinical attachment loss showed a wider range in PROM cases, with some women exhibiting severe loss compared to controls. Overall, these findings suggest a strong association between PROM and compromised periodontal health.Similarly, Esercan A, Demir I¹⁵ the correlation analysis demonstrated that systemic inflammatory markers were positively associated with oral health indices. Leukocyte count showed the strongest positive correlation, particularly with periodontal depth (ρ = +0.60) and gingival index (ρ = +0.58). NLR also exhibited consistent positive correlations across all indices, with the highest for periodontal depth. PLR and PCT followed a similar trend, though with weaker correlations. Conversely, MPV and MPV/PLT ratio showed weak negative correlations, suggesting an inverse relationship with oral disease parameters. MLO values had very weak positive correlations, which were not clinically significant. Overall, these findings highlight that systemic inflammatory markers are more closely related to oral disease severity than platelet indices.Temur, I., Temur, K.T., Donertas, S.N. et al.¹⁹ the case group showed significantly higher oral health indices than the control group, with median DMFT

scores of 7.14 vs. 4.74 (p=0.013), DMFS scores of 20.58 vs. 12.08 (p=0.026), PI values of 1.96 vs. 1.18, GI values of 2.03 vs. 1.20, and PD values of 2.61 mm vs. 2.00 mm (all p<0.001).

This study demonstrates a significant association between PROM, systemic inflammation, and compromised oral health. Women with PROM exhibited higher inflammatory markers, including leukocyte count, NLR, PLR, and PCT, compared to controls, indicating an enhanced systemic inflammatory response. Oral health parameters such as DMFT, plaque index, gingival index, and periodontal depth were also worse in the PROM group, reflecting poor oral hygiene and advanced periodontal involvement. Correlation analysis revealed that systemic inflammatory markers were positively associated with oral disease severity, whereas platelet indices (MPV, MPV/PLT ratio) showed weak or negative correlations. Additionally, PROM was more frequent in multiparous women and at earlier gestational ages, suggesting maternal factors may contribute to its occurrence. Overall, these findings underscore the importance of maintaining good oral hygiene and monitoring inflammatory status during pregnancy to potentially reduce the risk of PROM.

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