Ishaque et al. BMC Public Health 2011, 11(Suppl 3):S3 http://www.biomedcentral.com/1471-2458/11/S3/S3 Page 4 of 12 Number of studies identified (n = 1155) Records screened (n = 1155) Full text articles assessed for eligibility (n = 84) Studies included in the meta analysis (n = 25) Records excluded (n = 1071) Full text articles excluded (n = 59) Syphilis= 8 Malaria=6 HIV=6 Bacterial Vaginosis: 5 Figure 1 Flow diagram showing identification of studies. Chorioamnionitis The Cochrane review by Kenyon et al. [38] studies the use of antibiotics for preterm premature rupture of mem- brane (pPROM) and reports a statistically significant 43% reduction in risk of chorioamnionitis (RR = 0.57; 95% CI: 0.37 – 0.86). There was however no impact on perinatal mortality/or fetal death before discharge (RR = 0.90; 95% CI: 0.74 – 1.10). Another Cochrane review by Flenady and King [39] on antibiotics for PROM at or near term showed no impact of antibiotics on chorioamnionitis (RR = 0.60; 95% CI: 0.30 – 1.18) nor on perinatal mortality (RR = 0.98; 95% CI: 0.14 – 6.89). There were no separate data on stillbirth. Asymptomatic bacteriuria Studies have looked at the association between asympto- matic bacteriuria during pregnancy and perinatal mor- tality. In a study performed from 1972 to 1979, pregnant women with asymptomatic bacteriuria had a significantly higher perinatal mortality (64.9 vs. 15.6, p < 0.001) [40]. However, a more recent population-based retrospective study by Sheiner et al. showed that patients with asymptomatic bacteriuria, in whom anti- biotic treatment was recommended, had similar perina- tal mortality rates compared to women without asymptomatic bacteriuria (1.5% vs. 1.4%, P = 0.707) [41] Periodontal disease While published data convincingly display a link between periodontal disease and stillbirth incidence [10,15,42-44], there is limited literature on interventions for periodontal disease and impact on stillbirths. The systematic review by Polyzos et al. [14] studied the impact of periodontal care during pregnancy and found a non-significant effect on abortions and stillbirths (OR = 0.73; 95% CI: 0.41 to 1.31). In a recent randomized controlled trial, 1082 pregnant women with periodontal disease were allocated either to receive periodontal treatment in mid-pregnancy or after delivery. There were four unexplained stillbirths in the control group