Condition category
Pregnancy and Childbirth
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Prof Hong Yan


Contact details

No 76 Western Yanta Road
+86 (0)29 8265 5001

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Impact of iron/folate versus multi-micronutrient supplementation during pregnancy on birth weight: a randomised controlled trial in rural Western China


Study hypothesis

1. The newborn infants of women receiving the multi-micronutrient supplements will at least experience a 50% reduction in prevalence of low birth weight (less than 2500 g) in comparison those receiving folate alone.
2. The newborn infants of women receiving the iron/folate supplements will at least experience a 25% reduction in the prevalence of low birth weight (less than 2500 g) in comparison those receiving folate alone
3. The women receiving the multi-micronutrient supplements in comparison those receiving iron/folate supplements, will at least experience a 30% reduction in the prevalence of anemia (Haemoglobin [Hb] less than 11 g/dL) in the third trimester (30 to 32 weeks of gestation).

Ethics approval

Committee for Science and Research at the Xi'an Jiaotong University, 10/04/2002, ref: 2002002

Study design

Grouped randomised double-blind controlled community trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use contact details to request a participant information sheet


Low birth weight; preterm delivery; anaemia


Hamlets were randomly assigned for women to receive one of the following three daily antenatal supplements:
1. Multi-micronutrients
2. Iron and folic acid
3. Folic acid alone (control)

The multi-micronutrient supplements were formuated to contain the Required Dietary Allowances (RDA) for each of the micronutrients and if taken throughout pregnancy should provide a sufficient intake of each micronutrient to correct any underlying deficiencies (30 mg iron, 400 µg folate, 15.0 mg zinc, 2.0 mg copper, 65.0 µg selenium, 150.0 µg iodine, 800.0 µg vitamin A, 1.4 mg Vitamin B1, 1.4 mg vitamin B2, 1.9 mg vitamin B6, 2.6 µg vitamin B12, 5.0 µg vitamin D, 70.0 mg vitamin C, 10.0 mg vitamin E, and 18.0 mg Niacin). The iron/folate supplements contained 60 mg of iron and 400 µg of folic acid. The folate-only supplement contained 400 µg of folic acid.

These supplements were identical in appearance and participants, investigators, field staff, and statisticians did nor know supplement codes until the study finished.

Intervention type



Drug names

Primary outcome measure

1. Duration of pregnancy
2. Birth weight, length and head circumference
3. Haemoglobin level of pregnant women at the start of their third trimester

Secondary outcome measures

1. Compliance with supplements
2. Side effects of supplements
3. Complications of pregnancy:
3.1. Hypertension and preeclampsia
3.2. Antepartum haemorrhage
3.3. Infections
4. Type of delivery and type of assistance
5. Delivery complications:
5.1. Prolonged labour
5.2. Postpartum haemorrhage
5.3. Duration of maternal hospital admission
6. Early neonatal morbidity

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

Women invited to participate in the trial must be less than 28 weeks of gestation

Participant type


Age group




Target number of participants

7144 eligible pregnant women

Total final enrolment


Participant exclusion criteria

Women will be excluded from the trial if already taking iron, folate, and other micronutrients supplements for more than two weeks

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

No 76 Western Yanta Road

Sponsor information


United Nations Children's Fund (UNICEF) (China)

Sponsor details

c/o Lilian Selenje
Health and Nutrition
12 Sanlitun Lu

Sponsor type

Research organisation



Funder type

Research organisation

Funder name

UNICEF (Project No.: YH101-H12/03)

Alternative name(s)

United Nations Children's Emergency Fund

Funding Body Type

private sector organisation

Funding Body Subtype

International organizations


United States of America

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

1. 2008 results in:
2. 2009 results in:
3. 2012 30-month follow-up results in:
4. 2015 results in:
5. 2016 results in:
6. 2018 results in:
7. 2019 results in: (added 12/08/2019)

Publication citations

  1. Results

    Zeng L, Dibley MJ, Cheng Y, Dang S, Chang S, Kong L, Yan H, Impact of micronutrient supplementation during pregnancy on birth weight, duration of gestation, and perinatal mortality in rural western China: double blind cluster randomised controlled trial., BMJ, 2008, 337, a2001.

  2. Results

    Cheng Y, Dibley MJ, Zhang X, Zeng L, Yan H, Assessment of dietary intake among pregnant women in a rural area of western China., BMC Public Health, 2009, 9, 222, doi: 10.1186/1471-2458-9-222.

  3. Results

    Wang W, Yan H, Zeng L, Cheng Y, Wang D, Li Q, No effect of maternal micronutrient supplementation on early childhood growth in rural western China: 30 month follow-up evaluation of a double blind, cluster randomized controlled trial., Eur J Clin Nutr, 2012, 66, 2, 261-268, doi: 10.1038/ejcn.2011.190.

  4. Results

    Li C, Zeng L, Wang D, Yang W, Dang S, Zhou J, Yan H, Prenatal Micronutrient Supplementation Is Not Associated with Intellectual Development of Young School-Aged Children, J Nutr, 2015.

Additional files

Editorial Notes

12/08/2019: Publication reference and total final enrolment added. 11/07/2018: Publication reference added. 28/07/2016: Publication reference added.