Modifiable Risk Factors Associated with Adverse Perinatal Outcomes in Bangladesh

Abstract

Background Globally, perinatal mortality accounts for approximately five million deaths (2.6 million stillbirths and 2 million early neonatal deaths) every year. Further, low birthweight which is a major adverse perinatal outcome constitutes more than 20 million births every year. Approximately 97%-99% of these adverse perinatal outcomes occur in low- and middle-income countries including Bangladesh. In Bangladesh, the burden of perinatal mortality remains high at 44 deaths per 1,000 pregnancies and low birthweight accounts for approximately 36% of births every year, yet many modifiable factors associated with these adverse perinatal outcomes remain under-investigated in the country. Aim and objectives The primary aim of this thesis was to gain a deeper understanding of modifiable risk factors contributing to adverse perinatal outcomes in Bangladesh. The specific objectives included investigating the association between polluting cooking fuels and perinatal mortality (stillbirth and early neonatal mortality) in Bangladesh; examining the effect of short and long birth intervals on adverse perinatal outcomes (first-day neonatal mortality, early neonatal mortality and small birth size) in Bangladesh; exploring community perceptions on birthweight and care practices for low birthweight infants in Bangladesh; and identifying modifiable socio-cultural factors influencing women’s early and adequate utilisation of antenatal care in rural Bangladesh. Methods In this thesis, both quantitative and qualitative methods were used. For the quantitative analyses (studies I and II), data were derived from the Bangladesh Demographic and Health Surveys (BDHS) from the years 1996-1997, 1999-2000, 2004, 2007, 2011 and 2014. Bivariate and multivariable analyses were conducted to obtain the crude and adjusted odds ratio (aOR) respectively. Wald test was used to assess statistical significance with a 95% confidence interval (CI). The ‘svy’ command was used in all the analyses to calculate the weighted values in order to adjust for the clustering effect and sample stratification. Data for the qualitative analyses (studies III and IV) were derived from the results of in-depth interviews, key-informant interviews and focus group discussions conducted in two rural settings of Bangladesh. In total, 32 in-depth interviews were conducted with 11 pregnant women, 12 recently delivered women, four husbands whose wives were pregnant or had a recent birth, and five mothers-in-law whose daughters-in-law were pregnant or had a recent birth. Two focus group discussions were conducted with husbands with eight participants in each and four key-informant interviews were conducted with community health workers. Thematic analysis was used to analyse the data. Results Study I included in this thesis examined the association between polluting cooking fuels (kerosene, coal/lignite, charcoal, wood, straw/shrubs/grass, agricultural crop and animal dung) and perinatal mortality (stillbirth and early neonatal mortality) using BDHS data from the years 2004, 2007, 2011, and 2014. In the multivariable analysis, maternal exposure to polluting fuels compared with exposure to clean fuels (electricity, liquefied petroleum gas, natural gas, and biogas) was associated with early neonatal mortality (aOR: 1.46, 95% CI: 1.01, 2.10); however, no association was found for stillbirth (aOR: 1.25, 95% CI: 0.85, 1.84). While examining the impact of each type of polluting fuels on perinatal mortality, the association with perinatal mortality varied by types of polluting fuels. Maternal exposure to agricultural crop waste as the main fuel was associated with increased odds of both stillbirth (aOR: 1.76, 95% CI: 1.10, 2.80), and early neonatal mortality (aOR: 1.78, 95% CI: 1.13, 2.80). Maternal exposure to wood as the main fuel posed greater odds for early neonatal mortality (aOR: 1.52, 95% CI: 1.04, 2.21). Using polluting cooking fuels in an indoor kitchen was associated with four times higher odds of stillbirth (aOR: 4.12, 95% CI: 1.49, 11.41). Study II of this thesis was an investigation of the effect of short (<36 months) and long (≥60 months) birth intervals on adverse perinatal outcomes including first-day neonatal death, early neonatal death and small birth size using BDHS data from the years 1996-1997, 1999-2000, 2004, 2007, 2011 and 2014. In the multivariable analysis, infants with a birth interval of <36 months had increased odds of first-day neonatal mortality (aOR: 2.11, 95% CI: 1.17, 3.78) and early neonatal mortality (aOR: 1.58, 95% CI: 1.13, 2.22) compared with births spaced 36-59 months. A birth interval of ≥60 months was associated with increased odds of first-day neonatal mortality (aOR: 2.02, 95% CI: 1.10, 3.73) and small birth size (aOR: 1.17, 95% CI: 1.02, 1.34) compared with births spaced 36-59 months. In this study, maternal perception of an infant’s size at birth was very “small” or “smaller than average”, was used as a proxy for “low birthweight” due to the lack of birthweight estimates in Bangladesh. Using a qualitative design, study III aimed to gain an insight into the families’ perceptions on birthweight, including local meaning, terminology and causes of different categories of birthweight and families’ preventive and care practices for a low birthweight infant in the rural community of Bangladesh. Birthweight was not well-recognised and often excluded from the assessment criteria of a newborn’s health status in rural Bangladesh. Low birthweight was not considered as a criterion of an infant’s illness unless the infant appeared unwell. A common belief that giving birth to a small infant could avoid pregnancy complications and caesarean section, predominantly restricted women’s adoption of preventive practices of low birthweight, such as, pregnant women’s adequate and nutritious food consumption. Common practices to treat a low birthweight infant who appeared ill included breastfeeding, feeding animal milk, feeding sugary water, feeding formula, oil massage, and seeking care from formal and informal care providers including a spiritual leader. Care-seeking for a low birthweight infant was often delayed in the rural community due to financial constraints, home birth and several socio-cultural factors including maternal lack of decision-making autonomy and superstition. The contribution of the socio-cultural factors to the delays occurring in antenatal care utilisation in rural Bangladesh was a key focus in study IV. There were various socio-cultural factors in the rural community that influenced women’s early initiation of antenatal care, which subsequently hindered women’s adequate utilisation of antenatal care. Women’s lack of awareness on the appropriate timing of the first antenatal care contact, lack of decision-making autonomy and fear of medical interventions were the major barriers to early and continued antenatal care utilisation. There were many superstitions around pregnancy in the rural setting which prevented women seeking early and adequate antenatal care and led them to seek care from unskilled traditional care providers whose treatments were associated with several harmful practices. Conclusion The findings of this thesis highlight the importance of various factors associated with adverse perinatal outcomes which are modifiable within the context of existing programs in Bangladesh and potentially in other low- and middle-income countries. This thesis sheds light on the deleterious effect of polluting cooking fuels on the perinatal outcomes which could be modified with clean cooking interventions. Birth intervals shorter than 36 months and longer than 59 months are found to be associated with a range of adverse perinatal outcomes. Promoting an optimal birth interval of 36-59 months through postpartum family planning may reduce adverse perinatal outcomes. In rural Bangladesh, a lack of awareness of birthweight persists, which along with socio-cultural factors constrain preventive and care-seeking practices for a low birthweight infant. There are also various socio-cultural barriers contributing to the delayed and inadequate antenatal care utilisation of rural women in Bangladesh. Targeting these socio-cultural barriers with context- and community-specific interventions could prevent delays at the community level which would lead to significant improvements in perinatal outcomes.