Vaz 2017.

Methods	RCT: NCT01660165
Participants	60 women randomised Inclusion criteria: women 5‐13 weeks' gestation; aged 20‐40 years at the time of enrolment; free from any known chronic diseases; residing in the study catchment area; intending to continue prenatal care in the public health centre; classified as at risk for postpartum depression (reported a past history of depression or presented a depressive symptom score at baseline ≥ 9 based on the EPDS). Exclusion criteria: depressed or presented with psychotic symptoms; past history of mania; or at suicidal risk; or taking any psychiatric medication (as anti‐depressives and anxiolytics); or being seen by a psychologist or psychiatrist. Women taking any oil supplementation (such as fish oil, flaxseed oil or cod liver oil), were also excluded. Setting: Rio de Janeiro, Brazil (enrolled November 2009‐October 2011 and the last follow‐up visit occurred in July 2012).
Interventions	SUPPLEMENTATION: omega‐3 versus placebo Group 1: omega‐3: 6 capsules/day, 1 g each, for a total dose of 1.8 EPA and 0.72 g DHA (The capsules were deodorised, and contained 0.2 mg/g of vitamin E as antioxidant. Women were advised to take 3 capsules at lunch and 3 capsules at dinner): n = 32 Group 2: placebo: n = 28 Timimg of supplementation: second trimester to 16 weeks postpartum All women: 400 µg/day of folic acid from the beginning of pregnancy, and 60 mg/day ferrous sulphate from the 2nd trimester until birth, as provided during standard prenatal care in Brazil. Participants were asked to not alter their usual dietary habits and not consume any supplements other than the ones provided by the research team and antenatal care service. DHA + EPA dose/day: high: 720 mg DHA + 1.8 g EPA
Outcomes	Women/birth: length of gestation; depression (at 30‐32 weeks' gestation and 4‐6 weeks postpartum); adverse effects (gastrointestinal and non‐gastrointestinal); EPA, DHA and omega‐6/omega‐3 concentrations Babies/infants/children: birthweight The EPDS was used to measure depression, and scored at 5‐13 weeks' gestation, 22‐24 weeks' gestation (baseline for RCT), 30‐32 weeks' gestation, and 4‐6 weeks postpartum. The Portuguese version of the scale was validated in a sample of mothers from Pelotas, southern Brazil. EPDS score of ≥ 11 was the cut off for depressive symptoms.
Notes	The fish oil supplement was manufactured by Galena Nutrition Quίmica Industrial, São Paulo, Brazil. Funding: “The present study was supported by Carlos Chagas Filho Foundation for Research Support of Rio de Janeiro State (Grant No. E‐26/112.181/2012). The funding institution did not have any role in study design, data collection, analysis, and interpretation of results, writing the manuscript or in the decision to submit the manuscript for publication”. Declarations of interest: “The authors declare they have no competing interests”.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "The randomization was performed by a researcher not involved in the data collection using the participant identification (subject ID) after stratification for EPDS score and previous history of depression”.
Allocation concealment (selection bias)	Unclear risk	Quote: "The randomization was performed by a researcher not involved in the data collection using the participant identification (subject ID) after stratification for EPDS score and previous history of depression”.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: “Participants and all research assistants and technicians responsible for running both the cohort study and the RCT were blinded to the study allocation”
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No information provided by the authors on whether assessors were blinded, for any of the outcomes reported.
Incomplete outcome data (attrition bias) All outcomes	High risk	Of the 32 women randomised to the intervention, 6 did not receive intervention (2 transferred antenatal care to another health centre; 3 exceeded 13 weeks of gestation at the baseline), and 7 dropped out before the end of pregnancy time‐point, leaving 17/32 women (53%) contributing data to the analysis for end of pregnancy/birth outcomes. A further 2 women were lost to follow‐up before the 4‐6‐week postpartum data collection time point (did not visit); therefore only 15/32 women (47%) of the women randomised to the intervention were included in the analysis for the postpartum outcomes. Of the 28 women randomised to the control, 4 did not receive intervention (1 transferred prenatal care to another health centre; 1 miscarriage; 2 missed 2nd trimester visit), and 5 dropped out before the end of pregnancy time‐point, leaving 17/28 women (60%) contributing data to the analysis for end of pregnancy/birth outcomes.
Selective reporting (reporting bias)	Unclear risk	Reporting of birthweight and GA incomplete (the total number of participants in the groups is not reported).
Other bias	Unclear risk	Baseline characteristics similar between except for ethnicity.

Abbreviations:

2D: 2‐dimensional

AA: arachidonic acid; ALA: alpha‐linolenic acid; AIDS: acquired immune deficiency syndrome; ADA: American Diabetes Association;ASQ: Ages and Stages Questionnaire

BASC‐PRS: Behaviour Assessment for Children: Parent Rating Scale;BDI: Beck Depression Inventory;BMI: body‐mass index; BP: blood pressure; BPD: bronchopulmonary dysplasia; BSID: Bayley Scales of Infant Development

CES‐D: Center for Epidemiologic Studies Depression Scale; CRP: C‐reactive protein

DBP: diastolic blood pressure; DHA: docosahexaenoic acid; DNA: deoxyribonucleic acid; DPA: docosapentaenoic acid;DSM: Diagnostic and Statistical Manual;

EPA: eicosapentaenoic acid; EPDS: Edinburgh Postnatal Depression Scale; ERG: electroretinography;ERP: electroencephalography/event‐related potentials; ESOMAR: European Society for Opinion and Marketing Research; ETA: eicosatetranoic acid; EU: European Union

FADS: fatty acids desaturase; FDA: Food and Drug Administration; FFQ: food frequency questionnaire; FiO2: fraction of inspired oxygen; FPG: fasting plasma glucose

GA: gestational age; GDM: gestational diabetes mellitus; GLA: gamma linolenic acid; GWG: gestational weight gain

HAM‐D: Hamilton Rating Scale Depression; Hb: haemoglobin; HbA1c: glycated haemoglobin; HC:AC: head circumference/abdominal circumference; HDL‐cholesterol: high density lipoprotein‐cholesterol; HDRS: Hamilton Rating Scale for Depression; HLA: human leukocyte antigen; HIV: human immunodeficiency virus; HOMA‐B: Homeostatic Model Assessment of Beta cell function; HOMA‐IR: Homeostatic Model Assessment of Insulin Resistance;HOME: home observation measurement of the environment

IgE: immunoglobulin E; IGF: Insulin‐like growth factor; IL: interleukin;IQ: intelligence quotient; IQR: interquartile range;IU: international units; IUGR: intrauterine growth restriction; IVH: intraventricular haemorrhage

K‐ABC: Kaufman Assessment Battery for Children; K‐CPT: Conners Kiddie Continuous Performance Test

LA: linoleic acid; LC: long‐chain; LCPUFA: long‐chain polyunsaturated fatty acid; LGA: large‐for‐gestational age

MADRS: Montgomery–Åsberg Depression Rating Scale; MD: Maryland;MDI: mental development index (BSID);MRI: magnetic resonance imaging; mRNA: messenger ribonucleic acid; MTHF: methyltetrahydrofolic acid

n‐3: omega‐3; n‐6: omega‐6; n‐9: omega‐9; NBAS: Neonatal Behavioral Assessment Scale; NCT: ClinicalTrials.gov registry; NEC: necrotising enterocolitis; NICU: neonatal intensive care unit; NIDDK: National Institute of Diabetes and Digestive and Kidney Diseases; NIH: National Institutes of Health; NIMH: National Institute of Mental Health;NOS: neurological optimality score;NSAIDS: nonsteroidal anti‐inflammatory drugs

OGTT: oral glucose tolerance test

PDI: psychomotor development index (BSID); PDI: postnatal depression inventory; PDSS: Postpartum Depression Screening Scale;PE: pre‐eclampsia; PG: prostaglandin; PI: pulsatility index; PIH: pregnancy‐induced hypertension; PONCH: Pregnancy Obesity Nutrition and Child Health Study; PPH: postpartum haemorrhage; PPROM: preterm prelabour rupture of membranes

QUICKI: quantitative insulin sensitivity check index

RBC: red blood cell; RCT: randomised controlled trial; RDS: respiratory distress syndrome;RI: resistance index; ROP: retinopathy of prematurity

S/D: systolic/diastolic; SBP: systolic blood pressure;SD: standard deviation; SGA: small‐for‐gestational age; SiPS: Salmon in Pregnancy Study;sLORETA: standardised low‐resolution brain electromagnetic tomography

T1D: type 1 diabetes; TLR: toll‐like receptor; TOVA: Test of Variables of Attention

US: ultrasound; U.S. FDA: United States Food and Drug Administration

VLDL‐cholesterol: very low density lipoprotein‐cholesterol

WIC: Women, Infants and Children