Midwife observations on the impact of hot weather on poor perinatal outcomes in central Australia: a qualitative study

Abstract

Remote arid Australian towns already experience high summer temperature and are projected to have warmer future temperatures due to climatic changes. It is also home to many Indigenous women who prefer an outdoor lifestyle and have poor perinatal outcomes. Quantitative analysis of preterm birth and temperature data indicated higher risks to preterm births among Indigenous women in central Australia. This paper aims to report midwives’ observations on the effects of hot weather on poor perinatal outcomes in a central Australian town. Semi-structured interviews were conducted with 12 registered midwives providing perinatal services to families in central Australia. The interview responses were coded and classified against the major themes. None of the midwives perceived any direct relationship between heat exposure and preterm birth, but reported increased incidences of dehydration, exhaustion, discomfort and requests for induction among pregnant women which were often treated before further complications. A quarter of the respondents also mentioned that Indigenous pregnant women do not complain, even when symptoms of heat stress are evident. Quantitative analysis of perinatal and temperature data indicated increased risks to preterm births, but did not provide information on discomfort, dehydration, exhaustion or more requests to be induced. The study also shows that it is important for midwives and health practitioners to be culturally-sensitive to the fact that certain population groups tend not to complain, even if they are experiencing symptoms of heat stress. This research highlights the importance of cultural training for midwives and their role in alerting pregnant women to take precautionary measures during summer periods. Introduction Poor perinatal outcomes such as stillbirths (baby born with no signs of life at or after 28 weeks’ gestation) and preterm births (births before completing 37 weeks of gestation) often lead to economic costs and stress on families (Trasande et al., 2016; Ten Hoope-Bender et al., 2016; Petrou et al., 2001). Pre-term 1 Corresponding author 99 Learning Communities | Number 24 – October 2019 births were one of the leading causes of death among children under the age of 5 years (WHO, 2016a). Globally, for every 1000 births, around 18 babies were still born in 2015 (WHO, 2016b). Preterm infants are likely to experience short and long term health problems and even permanent disability (Petrou et al., 2001; Wen et al., 2004; Soilly et al., 2014). Despite improved antenatal programs and access to technology to monitor pregnancy, the incidence of poor pregnancy outcomes such as preterm births have risen globally in the past two decades (Blencowe et al., 2012). While preterm births are highest in low income countries (Beck et al., 2010), such risks are also quite high among Indigenous populations in high income countries such as Australia, Canada and the United States (Shah et al., 2011; Heaman et al., 2005). In Australia, the rate of Indigenous preterm birth and perinatal mortality is nearly double that of the non-Indigenous population making it important to understand factors that may influence such poor perinatal outcomes (AIHW, 2016b; AIHW, 2017). Several risk factors have been linked to preterm births, low birth weights and stillbirths. Maternal characteristics (e.g. age), maternal medical conditions (e.g. overweight, diabetes, high blood pressure), maternal reproductive history (personal or family history of preterm birth, previous preterm births or miscarriages) and general maternal health (nutritional status, infection and chronic disease, e.g. diabetes and hypertension) include some of the risk factors (AIHW, 2016a; AIHW, 2017; AIHW, 2016b; Goldenberg et al., 2008; Flenady et al., 2011). Certain fetal characteristics such as multiple pregnancies, small for gestation age and growth restriction also contribute towards poor perinatal outcomes (AIHW, 2016a; AIHW, 2017; AIHW, 2016b). Other risk factors include social factors such as low education, domestic violence, poor socio-economic conditions (Negger et al., 2004; Chiavarini et al., 2012), Indigeneity (e.g. 16% preterm births compared to 6% preterm births for non-Indigenous Australian mothers) and access to antenatal care (e.g. living in very remote locations or locations with low access to antenatal care) (AIHW, 2016a; AIHW, 2017; AIHW, 2016b, Goldenberg et al., 2008). Exposure to environmental variables such as extreme temperature, humidity, ozone, carbon monoxide, nitrous oxide and particulate matter (Trasande et al., 2016; Strand et al., 2011a; Basu et al., 2010; Dadvand et al., 2011; Flouris et al., 2009; Zhang et al., 2017; Wang et al., 2013) and certain lifestyle choices such as use of alcohol and other drugs (Flenady et al., 2011; Varner et al., 2014) also contribute to poor perinatal outcomes. A few Brisbane based studies have explored the impact of ambient temperature (Strand et al., 2011b; Li et al., 2018) and heat waves (Wang et al., 2013) and identified increased preterm birth risks. Another study in arid Australia indicated statistically significant increase in risks of preterm births due to exposure to extreme maximum temperature (>41°C) during the last 3 weeks of pregnancy (Mathew et al., 2017). Environmental risk factors such as exposure to extreme heat and its impact on perinatal outcomes have been under-researched in Australia. All the existing Australian studies exploring the association between heat exposure and perinatal outcomes used hospital level health record data. The studies did not collect place-based data or explore the impact of temperature exposure on less severe heat related health symptoms such as dehydration or tiredness. This paper focuses on the same geographical area as Mathew et al. (2017) and aims to explore further the issue using midwives’ observations on the effects of hot weather on poor perinatal outcomes. Specifically, the paper explores the following research questions: What impacts of heat are observed among pregnant women in a central Australian town? What are the factors that might be contributing towards the impact? Do the observed impacts differ for specific groups of the population?