==== Front BMC Public Health BMC Public Health BMC Public Health 1471-2458 BioMed Central London 9917 10.1186/s12889-020-09917-6 Research Article ‘I decided to go back to work so I can afford to buy her formula’: a longitudinal mixed-methods study to explore how women in informal work balance the competing demands of infant feeding and working to provide for their family Luthuli Silondile 1 Haskins Lyn 1 Mapumulo Sphindile 1 Rollins Nigel 2 http://orcid.org/0000-0003-4395-1423Horwood Christiane horwoodc@ukzn.ac.za 1 1 grid.16463.360000 0001 0723 4123Centre for Rural Health, University of KwaZulu-Natal, Durban, South Africa 2 grid.3575.40000000121633745Department of Maternal, Newborn, Child and Adolescent Health, World Health Organization, Geneva, Switzerland 2 12 2020 2 12 2020 2020 20 184715 7 2020 18 11 2020 © The Author(s) 2020Open AccessThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.Background In South Africa almost 2 million women work informally. Informal work is characterised by poor job security, low earnings, and unsafe working conditions, with high rates of poverty and food insecurity. The peripartum period is a vulnerable time for many working women. This study explored how mothers navigate the tension between the need to work and the need to take care of a newborn baby, and how this affects their feeding plans and practices. Methods A mixed methods longitudinal cohort method was employed. Informal workers were recruited in the last trimester of pregnancy during an antenatal visit at two clinics in Durban, South Africa. Data were collected using in-depth interviews and quantitative questionnaires at three time points: pre-delivery, post-delivery and after returning to work. Framework analysis was used to analyse qualitative data in NVIVO v12.4. Quantitative analysis used SPSSv26. Results Twenty-four participants were enrolled and followed-up for a period of up to 1 year. Informal occupations included domestic work, home-based work, informal trading, and hairdressing, and most women earned