Summary of findings for the main comparison. Periodontal treatment compared to no treatment for preventing adverse birth outcomes in pregnant women.
| Periodontal treatment compared to no treatment for preventing adverse birth outcomes in pregnant women | ||||||
| Patient or population: pregnant women considered to have periodontal disease after dental examination Settings: clinics and hospitals Intervention: periodontal treatment Comparison: no treatment | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | Number of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| No treatment | Periodontal treatment | |||||
| Gestational age (preterm birth < 37 weeks) | Study population | RR 0.87 (0.70 to 1.10) | 5671 (11 RCTs) | ⊕⊕⊝⊝ LOW1 | Preterm birth < 35 weeks and < 32 weeks were also reported. There was no evidence of a difference in preterm birth < 35 weeks (RR 1.19 (0.81 to 1.76), 2 studies; 2557 participants) and < 32 weeks (RR 1.35 (0.78 to 2.32), 3 studies; 2755 participants) (VERY LOW2 quality evidence) | |
| 131 per 1000 | 114 per 1000 (92 to 143) | |||||
| Birth weight (low birth weight < 2500 g) | Study population | RR 0.67 (0.48 to 0.95) | 3470 (7 RCTs) | ⊕⊕⊝⊝ LOW3 | Low birth weight < 1500 g was reported in 2 studies. There was no evidence of a difference in low birth weight < 1500 g (RR 0.80 (0.38 to 1.70); 2550 participants) (VERY LOW2 quality evidence) | |
| 126 per 1000 | 84 per 1000 (60 to 120) | |||||
| Small for gestational age | Study population | RR 0.97 (0.81 to 1.16) |
3610 (3 RCTs) | ⊕⊕⊝⊝ LOW4 | ||
| 115 per 1000 | 111 per 1000 (93 to 133) | |||||
| Perinatal mortality (including fetal and neonatal deaths up to the first 28 days after birth) | Study population | RR 0.85 (0.51 to 1.43) | 5320 (7 RCTs) | ⊕⊝⊝⊝ VERY LOW5 | ||
| 18 per 1000 | 16 per 1000 (9 to 26) | |||||
| Maternal mortality | 0% in both groups | Not estimated | 2134 (4 RCTs) | ‐ | ||
| Pre‐eclampsia | Study population | RR 1.10 (0.74 to 1.62) | 2946 (3 RCTs) | ⊕⊝⊝⊝ VERY LOW6 | ||
| 64 per 1000 | 70 per 1000 (47 to 104) | |||||
| Adverse effects of therapy | 0% in both groups | Not estimated | 2389 (4 RCTs) | ‐ | ||
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; RR: risk ratio | ||||||
| GRADE Working Group grades of evidence High quality: further research is very unlikely to change our confidence in the estimate of effect Moderate quality: further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate Low quality: further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate Very low quality: we are very uncertain about the estimate | ||||||
1Downgraded 2 levels: serious limitation ‐ high risk of bias due to other bias (imbalance in baseline characteristics); serious inconsistency ‐ substantial heterogeneity (I2 = 66%). 2Downgraded 3 levels: serious limitation ‐ high risk of bias due to attrition; very serious imprecision ‐ low number of events and wide confidence intervals including the risk of benefit and harm. 3Downgraded 2 levels: serious limitation ‐ high risk of bias due to attrition; serious inconsistency ‐ substantial heterogeneity (I2 = 59%). 4Downgraded 2 levels: serious limitation ‐ high risk of bias due to attrition; serious inconsistency ‐ substantial heterogeneity (I2 = 54%). 5Downgraded 3 levels: very serious limitation ‐ high risk of attrition and other bias due to early termination of trial; very serious imprecision ‐ low number of events and wide confidence intervals including the risk of benefit and harm. 6Downgraded 3 levels: serious limitation ‐ high risk of attrition bias; very serious imprecision ‐ low number of events and wide confidence intervals including the risk of benefit and harm.