Sadatmansouri 2006.

Methods	Study design: RCT Location: Iran Setting: not stated Recruitment period: not stated
Participants	Inclusion criteria: pregnant women 18‐35 years of age, with moderate or advanced periodontitis, in 13th to 20th week of pregnancy Exclusion criteria: women with a history of congenital heart disease requiring prophylactic antibiotics, diabetes, current use of corticosteroids, chronic renal disease, or with fetal congenital abnormality (evaluated by ultrasound until 20th week), obstetric disorders such as gestational diabetes, placenta previa, pre‐eclampsia eclampsia and polyhydramnios Periodontal disease: it was defined as women with at least 4 teeth, with at least 1 site of pocket depth of at least 4 mm, and clinical attachment loss of at least 3 mm Mean age (± standard deviation (years)): Group A = 29.1 ± 4.3, Group B = 28.4 ± 4.1 Gestational age: 13‐20 weeks History of preterm delivery: not stated Number randomised: n = 30 Number evaluated: n = 30
Interventions	A) Antenatal periodontal treatment (n = 15): first phase ‐ ultrasonic scaling and hand instrument root planing under local anaesthesia using lidocaine or mepivastesin, if needed; maintenance phase ‐ oral hygiene instructions, use of 0.2% chlorhexidine mouthrinse once a night for 1 week, and periodontal evaluation every fortnight before birth. No information on the expertise of the dental professional who administered intervention B) Postnatal periodontal treatment (n = 15) All women: repeated periodontal examination: 28th week of pregnancy for the control group and 2nd week after treatment in the intervention group (during the 30th week)
Outcomes	Probing depth; clinical attachment; bleeding on probing; preterm birth < 37 weeks; birth weight; gestational age at birth
Funding	No funding source stated
Notes	None of the subjects were excluded due to abortion, eclampsia, pre‐eclampsia, pregnancy diabetes, placenta previa and polyhydramnios
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "women were randomly divided into two groups" Comment: insufficient information
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	No postrandomisation exclusions or losses to follow‐up reported
Selective reporting (reporting bias)	Low risk	No apparent evidence of selective reporting bias (although perinatal mortality was not reported)
Other bias	Low risk	No indication of other sources of bias