Weight-management texts did not reduce weight in postpartum women over 12 months

Objective

To test the effectiveness of a postpartum behavioural intervention delivered by automated text messaging in reducing weight. Design

Two parallel group, multicentre, randomised controlled trial. Setting

Recruitment from five areas across the United Kingdom (Belfast, Bradford, Stirling, London and Cardiff) through healthcare and community pathways, including social media. Participants

A diverse sample of 892 women between 6 weeks and 24 months postpartum, aged 18 years or more and with a body mass index of 25 kg/m 2 or more, enrolled between May 2022 and May 2023: 445 were randomised to the intervention and 447 to an active control (comparator). Interventions

12 months of fully automated text messages with embedded behaviour change techniques and two-way messaging components to support weight loss and maintenance of weight loss in the postpartum period by targeting dietary, physical activity and weight management behaviours. The comparator group received 12 months of text messages on child health and development tailored to child age. Main outcome measures

Primary outcome – weight in kilograms at 12 months (end of intervention). Secondary outcomes recorded at 6 and 12 months were changes in weight (at 6 months), body mass index, proportions of women with weight gain more than 5 kg, waist circumference, self-reported dietary intake, physical activity and infant feeding practices. Results

674 (75.6%) participants were included in the primary analysis. There was no difference found in the adjusted mean weight change between the intervention and active control groups (−0.1 kg (95% confidence interval -1.0 to 0.8, P = 0.84). Sensitivity analyses did not change these results. There was a small improvement in Fat and Fibre Barometer scores at 12 months in the intervention compared with control group (adjusted mean difference 0.09, 95% CI: 0.04 to 0.14; P Conclusions

A 12 month automated, interactive behavioural weight management intervention delivered by text message did not support weight loss for postpartum women but did have a positive impact on diet, physical activity and infant feeding behaviours. Trial registration

ISRCTN Registry ISRCTN16299220 WHAT IS ALREADY KNOWN ON THIS TOPIC

Women desire support with self-care behaviours such as diet, physical activity and weight management in the postpartum period, but little support is currently available. There is a lack of acceptable and effective weight management interventions designed for women during the postpartum period. Most previous studies in the field have been affected by poor recruitment, high rates of attrition, lack of diversity and have not adequately considered the lived experience of women. Mobile technologies can offer a more flexible and individualised ‘any time, any place’ approach to behavioural weight management interventions that may be well suited to this stage of life. WHAT THIS STUDY ADDS

The trial methodology was highly acceptable to postpartum women, and recruitment and retention targets were met. Overall, a fully automated two-way text message intervention did not support weight loss in a diverse sample of postpartum women from the United Kingdom but did support positive changes in diet, physical activity and infant feeding behaviours. There was no differential effect of the intervention across socioeconomic or ethnic groups.