Condition category
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

Dr Semira Manaseki-Holland


Contact details

Public Health
Epidemiology & Biostatistics
University of Birmingham
B15 2TT
United Kingdom

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Investigation of the effect of swaddling upon psychomotor and mental development in children at 13 and 36 months of age in Mongolia: a randomised controlled trial


Study hypothesis

Null Hypothesis: Swaddled children do not have worst developmental scores at 13 months compared to non-swaddled infants.

Primary outcome study question:
1. What is the effect of tightly swaddled Mongolian infants upon their Bayley Scales of Infant Development (BSID-II) scores at around 13 months compared to those not swaddled?
2. What is the effect of tightly swaddled Mongolian infants upon their BSID-II scores at around 3.5 years compared to those not swaddled?

Secondary outcome study questions:
1. What are the BSID-II scores for our trial population as a sample of Mongolian infants?
2. What is the effect of swaddling upon the weight, height, head circumference of infants in Ulaanbaatar at 13 months?
3. What are the BSID-II scores for our trial population as a sample of Mongolian infants at 3.5 years of age?

Please note that this is the phase II and III study of the Swaddling and Health Research Project, phase I trial details can be found at:

Ethics approval

1. London School of Hygiene and Tropical Medicine (LSHTM) Ethics Committee approved on the 5th April 2001 (ref: ETH2003-04/107). Additional approval received on the 5th February 2003.
2. Ministry of Health (MOH) of Mongolia approved on the 15th January 2004 (ref: 3/124)

Study design

Randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Infant motor/psychosocial development


All infants were recruited at birth and randomised to swaddling versus non-swaddling groups. Babies were then followed up intensely for 7 months (see phase I for more details) and then not seen again until 12 months of age; they had another follow-up contact at 13 months of age (or as soon after this time when they came for testing). There was also another visit at 3.5 years of each to each child and family when background, morbidity and mother related data were collected, and children tested for development achievements..

Swaddling group:
The babies randomised into the swaddling group were to be swaddled in the common traditional Mongolian method as much as they felt comfortable at least until 7 months follow-up. Traditional swaddling in Mongolia was as follows:
Swaddling was a tightly wrapping (2 adult fingers pass under the cloth) of a baby in several layers of cloth, covered by one warmer blanket from head to toe in a straight position after birth for about six months. Two or three ropes were used across a baby's body for binding to avoid unwrapping. For the first three months baby was swaddled most of the day and night with changes of the soiled cloth made every three or eight hours. After this age, practice varies with reducing hours of swaddling, but most infants were swaddled during sleep at least until 7 - 12 months. Duration and tightness of wrapping decreased with age. Furthermore as the baby grew, swaddling clothes for indoor may not have covered the head and would enclose the legs, trunk and arms up to the infant's necks, while after 6 months, in some occasions it only enclosed up to the waist. In the swaddling group, there was expected to be some variation in the swaddling period after 2 to 3 months, but it was usually expected to be more than 17 in 24 hours for those living in colder dwellings. Since the non-swaddling clothes had to be provided with alternatives to the readily available swaddling clothes and blankets, the swaddled group were given a blanket and 3 cotton sheets at the time of recruitment.

Swaddling, a cultural norm, was not a difficult infant care practice to achieve in this study. Swaddled babies would often be placed horizontal on a bed or carried, and not positioned vertically as with some cultures.

Non-swaddling group:
The non-swaddling group were instructed not to swaddle at all. The Mongolian stores did not sell the required size and warmth of clothing required to keep a newborn infant warmly clothed during the Siberian winters of Mongolia. Our recruitment pilot, in September 2000, indicated that in order to enable this alternative childcare method to be possible for the families randomised to the non-swaddling group, the project needed to provide some alternatives. Therefore, at the time of recruitment, the project gave each family a sheepskin sleeping bag and hat, a cotton sleeping bag, 8 cotton 0 - 3 months outfits. At 4 and then 12 weeks, the non-swaddling group was given another sheepskin hat and 10 outfits of a bigger size, which would fit the babies until 6 months of age. Half the outfits were made in Mongolia and half were body-suits made in the UK and transported to Mongolia. The sleeping bags were designed in consultation with 'Grobags' company in England, who have worked closely with Professor Fleming (a collaborator with the study at Bristol University, and an international expert in infant temperature regulation and SIDS). The sleeping bags were made in Mongolia but the manufacturers applied specific requirements developed in the UK. The families were encouraged to make or buy their own additional outfits for their infants, but if they could not, the project ones given to them were supplied in a large enough number in order to allow for washing dirty outfits at the same time as wearing up to 3 layers of outfits for the cold winter.

The sleeping bags were to be used at the parent's discretion, but the sheepskin sleeping bag especially was thought to be particularly useful for the cold evenings and when going outside. A leaflet was prepared for each family to explain what outfits they should expect to receive and how to use these to clothe their baby.

In the non-swaddling group, it was expected that some families would not adhere to their instructions of not swaddling because of cultural pressures. To monitor compliance and obtain a measure of exposure, multiple sources of information were used:
1. A retrospective 24-hour history of swaddling/clothing: recorded by the field-workers during each 3-weekly home visit through recording the carer's descriptions of the style of dress/clothing/ swaddling and length of each during the past 24-hour within the 24-hour retrospective diaries (a kind of behaviour diary adapted to record swaddling/clothing pattern)
2. Direct observation of fieldworker during 3-weekly visits: of the dressing/clothing/ swaddling of each child and discreetly recording observations of the type of baby clothing items that each family washed and hung to dry on the day of visit (available for observation during the majority of visits)
3. Analysis of the 4-days prospective mother's diaries used for sleeping and crying/fussing outcome measure: as mother's own reported behaviour during 2 time periods
4. Unscheduled visits from a monitoring fieldworker: in order to estimate unreported non-compliance conducted for all families 1 to 3 times
5. End-study fieldworker impressions' questionnaire: of their impression about compliance in each family and the consistency and extent of accuracy of the reports from each family during each 3 months of child's life

For analysis, the first and third methods of exposure recordings above were quantifiable and were combined to reveal exposure to swaddling per child for use in per-protocol analysis. The other three methods detailed above were triangulated with the data from the diaries and concluded that over 95% of families' compliance was revealed through the 3-weekly 24-hour retrospective diaries and the 4-day prospective diaries.

Data was collected retrospectively at 13 months on the last dates of swaddling during day time and sleep. For the swaddling group most were after the 7 months follow-up. These were triangulated with the data from the phase I (mentioned in the hypothesis above).

Intervention type



Not Applicable

Drug names

Primary outcome measure

BSID-II, an internationally acclaimed test of mental and psychomotor development in early childhood, measured at 12 - 15 months of age and again at 3.5 years:
1. BSID-II mental scale: evaluates children’s sensory/perceptual acuities, discriminations, and response; acquisition of object constancy; memory learning and problem solving; vocalization and beginning of verbal communication; basis of abstract thinking; habituation; mental mapping; complex language; and mathematical concept formation
2. BSID-II psychomotor scale: evaluates the degree of body control; large muscle coordination; fine manipulatory skills of the hands and fingers; dynamic movement; postural imitation; and stereognosis (ability to recognize objects by sense of touch)

Test scores are reported as scaled scores based on the infant’s age, with a normed mean of 100 (SD = 15 points). Both scales have high correlation coefficients (0/83 and 0/77 respectively) for test-retest reliability.

Secondary outcome measures

Length or height, head circumference, or Mid Upper Arm Circumference (MUAC) in cm (to the nearest 0.5cm); and weight in grams. Measured at 12 - 15 months of age.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. All babies born in the only four maternity hospitals of Ulaanbaatar (greater than 95% births were in these facilities)
2. Within 48 hours of birth if resident of Ulaanbaatar
3. Mother was well enough to discuss consent

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Refusal to consent
2. Birth weight less than 2500 g
3. Less than 36 weeks gestation
4. Obvious congenital abnormalities (with clear medical consequences)
5. Need for infant intensive care treatment
6. Residence in ‘very warm’ apartments (defined by the mother) since a pilot study indicated such families considered the home to be too hot for the baby to be wrapped

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Public Health, Epidemiology & Biostatistics
B15 2TT
United Kingdom

Sponsor information


Individual Sponsor (UK)

Sponsor details

c/o Semira Manaseki-Holland
Public Health
Epidemiology & Biostatistics
University of Birmingham
B15 2TT
United Kingdom

Sponsor type




Funder type


Funder name

The Wellcome Trust (UK) (grant ref: 063468)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Funder name

United Nations Children's Fund (UNICEF) Mongolia office and Canada Fund (Mongolia) (ref: MON2003/2004.02)

Alternative name(s)

Funding Body Type

Funding Body Subtype


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

2007 results in

Publication citations

  1. Results

    Narangerel G, Pollock J, Manaseki-Holland S, Henderson J, The effects of swaddling on oxygen saturation and respiratory rate of healthy infants in Mongolia., Acta Paediatr., 2007, 96, 2, 261-265.

Additional files

Editorial Notes