Tarannum 2007.

Methods	Study design: RCT Location: India Setting: The Department of Obstetrics and Gynaecology, Dr BR Ambedkar Medical College and Hospital, Bangalore, Karnataka India Recruitment period: August 2004 to August 2005
Participants	Inclusion criteria: healthy pregnant women aged 18 to 35 years; single gestation between 9 and 21 weeks; with ≥ 20 completely erupted teeth, excluding the third molars, and women with ≥ 2 mm attachment loss at ≥ 50% of examined sites Exclusion criteria: current use of tobacco (smoking/smokeless) or alcohol; history of congenital heart disease, current use of corticosteroids, diabetes, asthma, glomerulonephritis, or hyperthyroidism; mothers with twin pregnancy and Rh factor isoimmunity, and clinically evident systemic infection, inadequate antenatal care (< 6 visits) Mean age (± standard deviation (years)): Group A = 23 ± 3.3, Group B = 22.9 ± 3.6 (P = 0.935) Gestational age: 9 to 21 weeks History of preterm delivery: not reported Number randomised: n = 220 Number evaluated: n = 188 (attrition n = 32: loss to follow‐up n = 16, spontaneous abortions n = 4, did not receive allocated intervention n = 12)
Interventions	A) Antenatal periodontal treatment (n = 120): plaque control instructions (rinsing twice daily with 0.2% chlorhexidine until periodontal therapy was completed) + scaling and root planing performed under local anaesthesia. Full‐mouth scaling and root planing was performed over 4 to 5 appointments, with a 1 week interval between appointments. Periondontal therapy was completed before 28 weeks gestation and maintenance therapy was provided (oral prophylaxis and reinforcement of oral hygiene instructions every 3 to 4 weeks until birth). Treatment was provided by a periodontist B) Control ‐ Plaque control (brushing) instructions only + checkups at 4 to 5‐week intervals (n = 100) All women: full‐mouth periodontal examination, including oral hygiene index (simplified); bleeding index, and clinical attachment level
Outcomes	Preterm birth (< 37 weeks); low birth weight (< 2500 g); gestational age at birth
Funding	Not stated
Notes	The authors claim to have undertaken intention‐to‐treat analysis involving all of the subjects regardless of whether they underwent the prescribed treatment, however, this is not reflected in the 'numbers evaluated'
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Coin flip
Allocation concealment (selection bias)	Unclear risk	Not stated
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not feasible
Blinding of obstetric outcome assessment (detection bias)	Unclear risk	Not stated
Incomplete outcome data (attrition bias) All outcomes	Low risk	Based on the intention‐to‐treat analysis applied to the treatment group, there was no difference in attrition between groups (16% versus 9%)
Selective reporting (reporting bias)	High risk	Periodontal data at follow‐up were not reported clearly
Other bias	Low risk	Some imbalance in numbers of women randomised to each group

BMI = body mass index; CAL = clinical attachment loss; PD = probing depth; RCT = randomised controlled trial; SRP = scaling and root planing.