Rivas‐Echeverria 2000.

Methods	RCT
Participants	127 women randomised Inclusion criteria: pregnant women < 29 weeks' gestation at high risk of PE, nulliparity, previous PE, obesity, hypertension, < 20 years old, diabetes, nephropathy, mean arterial pressure < 85 mmHg, positive roll‐over test, “black race”, family history of hypertension or PE, twin pregnancy, poor socioeconomic conditions Exclusion criteria: none reported Setting: Mérida, Venezuela
Interventions	SUPPLEMENTATION + OTHER AGENTS: omega‐3 ( + aspirin, vitamins C and E) versus placebo Group 1: fish oil capsules 3 times a day (omega‐3 content not reported); aspirin 100 mg 3 times a week, vitamin C 500 mg 3 times a day, vitamin E 400 IU a day; total number randomised = 63 Group 2: placebo (not further described); total number randomised = 64 Timing of supplementation: not reported DHA + EPA dose/day: unclear
Outcomes	Women/birth: PE; “no serious maternal or neonatal side effects of treatment occurred in either group”
Notes	Funding: none reported Conflicts of interest: none reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: “randomly divided”
Allocation concealment (selection bias)	Unclear risk	Quote: “randomly divided”
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: “triple‐blind”; probably done
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Not reported
Selective reporting (reporting bias)	High risk	Only 1 outcome fully reported.
Other bias	Unclear risk	Not sufficient reporting to determine risk of other bias.