Dasanayake 2002.

Methods	RCT
Participants	75 pregnant women and their foetuses were randomised. Inclusion criteria: women between 16 and 45 years of age attending a County Deparment of Health Maternal and Child Health Clinic during their second trimester of pregnancy, who planned to live in the study area for the next 4 years, and who had at least 10 teeth with no open cavities. Exclusion criteria: known to be HIV positive, no commitment to use the County Health Department Pediatric Clinic during the course of the study, plans to move out of the study area in the next 4 years, planned to breastfeed, or became pregnant during the trial Setting: a County Department of Health Maternal and Child Health Clinic (country and study dates not reported) Important health characteristics reported: women in the intervention group had a mean 51 (SD 1.0) log10S. mutans count; women in the control group had a mean 4.6 (SD 1.8) log10S. mutans count; none of the included women were known to be HIV+.
Interventions	Group 1 (n = 38 women randomised) Mothers received a 10% chlorhexidine varnish treatment, applied by trained dental hygienists. The varnish was applied to each subject 6 months after delivery, every four weeks. The first of these 4 applications coincided approximately with the eruption of the first tooth. Subsequent to the first set of 4 applications, a single application was given every 6 months. Group 2 (n = 37 women randomised) Mothers received a placebo varnish containing 1% hydroxypropyl cellulose, 0.2% quinine hydrocholoride and food colouring, at the same time intervals as the treatment group. Since there was a concern that polyurethane alone can reduce the S. mutans levels, normal saline was used as stage 2 for the control group. Intervention timing: varnish applied at 12, 18, 24, 30 and 36 months postpartum (intervention duration > 6 months) Theory or model used as a basis for intervention: not reported All participants: mothers received emergency restorative care and prophylaxis prior to receiving the start of the trial. Participants who developed new caries lesions during the study were referred to the County Department of Health for free restorative treatment.
Outcomes	Data in meta‐analysis for: primary outcome: none; secondary outcomes: mother DMFS index, mother DMFT index, adverse events for mother or child Narrative text for: child microbiological presence; mother microbiological presence Tabulated data for: adverse events for mother or child Additional outcomes that had not been prespecified: Child: none reported. Mother: none reported
Notes	Funding: Quote: “Oralife Inc. in Toronto Canada provided the therapeutic agents and partial funding for the study”. Declarations of interest: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Blinding of participants was achieved by use of the placebo varnish comparator, and addition of quinine and food colouring to the placebo vanish which made it similar to the chlorhexidine varnish in taste and appearance, ensured blinding of participants. Considering study personnel, not reported
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "A calibrated and fully blinded examiner performed dental examinations”.
Incomplete outcome data (attrition bias) All outcomes	Low risk	5/38 (13%) and 4/37 (11%) of the women randomised to the control group and their infants were lost to follow‐up.
Selective reporting (reporting bias)	Low risk	All outcomes reported as described initially
Other bias	Low risk	Quote: “Subsequent to randomization, the two groups of mothers were comparable in terms of age, race, baseline differences in infants’ gender, method of delivery, birth weight or the length of gestation (table 1)".