Laivuori 1993.

Methods	RCT (3‐arms)
Participants	18 women randomised Inclusion criteria: women with PE (admitted to hospital between 26 and 37 weeks' gestation because of BP consistently exceeding 140/100 mmHg; 8 women also had proteinuria) Exclusion criteria: none reported Setting: Helsinki, Finland
Interventions	SUPPLEMENTATION: omega‐3 versus LA + GLA (Primrose oil) versus placebo Group 1: fish oil: 10 MaxEPA capsules (180 mg EPA, 120 mg DHA per capsule): total number randomised: n = 5 (3) Group 2: primrose oil: 10 Preglandin capsules (375 mg linolenic acid and 45 mg gammalinolenic acid per capsule): total number randomised: n = 7 (4) Group 3: placebo (10 capsules each containing 500 mg of maize oil and 500 mg olive oil); total number randomised: n = 6 (5) All women: intervention between 31‐36 weeks' gestation; bed rest in hospital for 2 days before randomisation Median duration and range of supplementation was: fish oil: 32 days (13‐54) evening primrose oil: 17 days (7‐28) placebo: 24 days (14‐39) Women were advised to follow their normal diets. DHA + EPA dose/day: daily dose unclear
Outcomes	Women/birth: prostanoids (urine); clinical signs of PE; birthweight (reported as median and range); BP (reported as % of pretreatment levels)
Notes	2 women used betablockers (metoprolol 100 mg/day) and 1 used dihydrazaline 50 mg/day. No aspirin‐like drugs were allowed. No outcomes could be meta‐analysed Funding: Preglandin capsules (Suomen Rohdos, Turku, Finland); MaxEpa and placebo capsules (Orion OY, Kuopio, Finland) Declarations of interest: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Reported as “in randomized order”
Allocation concealment (selection bias)	Unclear risk	Sealed envelopes
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Capsules of identical appearance
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Not reported, but probably done.
Incomplete outcome data (attrition bias) All outcomes	High risk	6/18 (33%) women excluded: 3 women gave birth before samples could be collected and 3 additional women failed to collect adequate urine samples.
Selective reporting (reporting bias)	Unclear risk	Limited number of outcomes reported.
Other bias	High risk	Median length of supplementation differed substantially between the 3 groups.