Asemi 2016.

Methods	Double‐blind parallel‐arm RCT, individual randomisation, placebo controlled
Participants	Setting: clinics in Kashan, Iran. Dates of recruitment: March‐September 2012. Inclusion criteria: 46 women, 18‐40 with singleton pregnancy. Exclusion criteria: women with pre‐eclampsia, placental abruption and GDM (it appeared that women were excluded after randomisation).
Interventions	Experimental intervention: calcium‐vitamin D for 9 weeks from 25 weeks (500 mg calcium, 200 IU vitamin D per day). Total number randomised: n = 23. Control/comparison intervention: placebo pills of similar appearance. Total number randomised: n = 23. Women in both groups took iron and folic acid supplements.
Outcomes	Fasting plasma glucose, insulin metabolism, biomarkers of oxidative stress, vitamin D levels, BP, birth size, gestational age, mode of birth.
Notes	Author contacted re information about women excluded after randomisation. Funding: reported to be funded by a grant from the vice‐chancellor for research, Kashan university of medical sciences. Reported that supplements and placebo were provided by Shahre Daru Co, Tehran. CoI: reported no conflict of interest.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	It was reported that randomisation was by random numbers “taken from a computer”.
Allocation concealment (selection bias)	Unclear risk	Placebo controlled but method at point of randomisation not described
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not clear if staff blind. Placebo controlled but it was not clear if staff were aware.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not clear if outcome assessors blind, some outcomes may not be affected by lack of blinding.
Incomplete outcome data (attrition bias) All outcomes	High risk	4 women were excluded post‐randomisation for reasons that may have related to the intervention (participants that developed complications during the trial were excluded – we have added these back in and collected these data for our analysis).
Selective reporting (reporting bias)	Unclear risk	We had no protocol. Women were excluded post‐randomisation and no ITT.
Other bias	Unclear risk	Author contacted re post‐randomisation exclusions.