Korkmaz 2014.

Methods	Randomised double‐blind placebo‐controlled trial with 3 arms.
Participants	108 pregnant women with singleton pregnancies without a risk factor for poor pregnancy outcome, systemic disorder, any medication and any previous surgery attending outpatient clinic of Dr Sami Ulus Maternity and Women’s Health Training and Research Hospital, Ankara, Turkey.between November 2010 and January 2012. Women with iron‐deficiency anaemia (determined according to Hb lower than 110 g/L), pre‐existing diabetes, prior gestational diabetes, a history of stillbirth, multiple gestation, active chronic systemic disease and the smokers were excluded.
Interventions	Participants were randomly assigned to 1 of 3 groups: group 1 (n = 36) received 400 ug (0.4 mg) folic acid daily; group 2 (n = 36) received 60 mg elemental iron daily; group 3 (n = 36) received placebo. Supplementation started at 6th week of gestation until term.
Outcomes	Antepartum, intrapartum and neonatal information were abstracted from the antenatal medical records and from inpatient hospital records. Gestational age at delivery, Apgar (1st min), Apgar (5th min), birthweight (g), albumin (mg/dL), serum GGT (IU/L), weight gain (kg), post‐term deliveries (beyond the 42nd week of gestation), the preterm premature rupture of membranes (spontaneous membrane rupture before 37th week of gestation).
Notes	Gestational age at start of supplementation: early, if supplementation started before 20 weeks' gestation. Anaemic status at start of supplementation: non‐anaemic. Daily iron dose: 60 mg elemental iron. Iron release formulation: normal release preparation/unspecified. Iron compound: other/not specified. Malaria setting: malaria‐free.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation using a pre‐generated randomisation scheme created by the website randomization.com.
Allocation concealment (selection bias)	Low risk	All study medications were prepared by a clinician unaware of the patient’s allocated study group in identical drug packages.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Participants were blinded to the groups.Packages were given by a blinded attending physician.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Outcome assessors were blinded to the groups.
Incomplete outcome data (attrition bias) All outcomes	Low risk	There are no losses to follow‐up reported in any of the groups.
Selective reporting (reporting bias)	Unclear risk	There is insufficient information to permit judgement.
Other bias	Low risk	No other bias apparent.