JMIR Publications

ABSTRACT

Background:

There is limited individual-level personalised data measuring the effect of heat exposure on health outcomes. While technologies that provide individual-level continuous, physiological, and behavioural metrics are increasingly available, their use in low- and middle-income countries (LMICs) remains limited, where the implementation of mHealth and wearable devices faces unique challenges.

Objective:

To describe experiences from implementing wearable devices to track heat exposure and key physiological parameters among pregnant and postpartum women in Tshwane, South Africa.

Methods:

Pregnant women (gestational age 30-36 weeks) were enrolled and trained on the use of a wearable Fitbit Inspire 3 activity tracking device worn on their wrist, with an iButton temperature monitor attached. Women were asked to wear the device daily, from enrolment up to six weeks postpartum; with data downloads every 4-6 days. The devices collected data periodically on ambient temperature, sleep, physical activity and heart rate. At study exit, women completed questionnaires about their experiences with the wearables.

Results:

Of 25 women enrolled, 64% lived in informal dwellings, 92% had iron sheet roofing, and 35% lacked access to electricity, necessitating frequent home visits by study staff to provide wearable charging via power banks. Internal storage on the FitBit device was limited to 7-days so data downloads were required every 4-6 days. Among 22 women who completed the study, time wearing the device for over four hours per day accounted for 37.0% overall during the study period but varied considerably between participants. Women reported feeling unsafe wearing the device (24%) and forgetting or not wearing it while doing daily chores (15%). Wear-time improved after engagement to encourage and support more regular use of the devices through additional counselling during study visits to download the data. Women reported the wearables increased awareness of their activity levels, motivating them be more active.

Conclusions:

The study describes our experiences with wearable devices use among pregnant women predominantly living in informal settlements with limited access to basic services and poor dwelling infrastructure. The influence of access to physiological parameters and its impact on personal activity has not been previously reported in this population. Despite high cellphone penetration, which can facilitate the use of mHealth technologies, significant implementation challenges remain in terms of access to smartphones to sync data, electricity supply, user safety concerns, and data completeness.