This study provides evidence that along with the socio-demographic factors known to be associated with a high prevalence of SBI in Bangladesh 14,19,27, area-level variations are also important. This is the first study in the Bangladesh context that explored the factors determining such area level variations, including factors responsible for SBI hot spots and cold spots. Unemployed women, those who gave birth to three or more children, experienced the death of a child, or whose husbands received no formal education were significantly more likely than others to be located in SBI hot spots. Women who gave their first birth at the age of 19 years or earlier and 20–34 years were significantly more likely to be living in SBI cold spots. These findings are robust as we have selected these variables following a proper statistical model-building technique. Therefore, we believe these findings are reliable and implications in designing policies and tailored programs.
The observed prevalence of SBI (26%) is consistent with the results of a nationally representative study conducted recently in Bangladesh 28 and in the range of SBI (19%-66%) reported in LMICs 29,30. This study also found a relatively high prevalence of SBI in the Sylhet division, where a majority of SBI hot spots are located. On the other hand, SBI cold spots are mainly located in parts of the Rajshahi and Khulna divisions. This is a new observation for Bangladesh. These divisional variations in SBI hot spots and cold spots are due to the division-level variations in socio-demographic and cultural characteristics of women and their partners and their perceptions regarding the desired number of children.
Previous studies in Bangladesh consistently reported high rates of early marriage, relatively low age at first birth, and low rates of formal education in the Sylhet division 31,32. These characteristics, both individually and together, can affect SBI. Our results also suggest that these factors are the significant predictors of SBI in the SBI hot spots area in the Sylhet division. A possible reason for such association is that couples with these characteristics are less likely to access maternal healthcare services, including intrapartum, birthing, and post-partum care 33–35. Moreover, in the current form of maternal healthcare services delivery in Bangladesh, post-partum care visit on the fourth weeks of the live birth is dedicated to providing counselling regarding family planning and contraception 36. This approach is not helpful in increasing family planning and contraception services because post-partum care visits at the fourth week of live birth are still very low in Bangladesh 36. Indeed, many women in Bangladesh have a misapprehension that once a live birth has occurred, the issue of pregnancy is over, and it is unnecessary to visit a healthcare center for post-partum care, particularly at the fourth week of live birth. This tendency is even higher among women of disadvantaged backgrounds. Consequently, many women end up with another pregnancy in a short interval. Additionally, women with these characteristics are less likely to receive family planning counselling which is offered at the household level by family planning workers 37.
Although the underlying reasons for such low use of services in the Sylhet division have yet not been explored, we believe this is mainly due to inadequate knowledge of reproductive goals 37. Moreover, there are studies in Bangladesh, including the Sylhet division, that found women of disadvantaged backgrounds are highly influenced by religious misconceptions. For instance, many couples believe that the religion Islam (the religion of over 90% of the population in Bangladesh) supports taking children as many as they want, and contraception use is comparable to the killing of humans 37–39. Consequently, the current approach to family planning services, including visits to women’s homes by family planning workers every 14 days to provide reproductive counselling and contraception, may not work effectively in this division. Indeed, several recent studies reported a high prevalence of unmet need for contraception and particularly modern contraception in Sylhet compared to the other divisions 40,41. Also, the prevalence of unintended pregnancy in this division is higher than in other parts of Bangladesh 37,42, and most of them occur in shorter intervals of the previous births 27. Also, a relatively high proportion of men in the Sylhet division is either migrated aboard or locally 43. Women having migrated partners are less likely to receive maternal healthcare services, a finding reported in Nepal 44 and Bangladesh 45. Consequently, they have inadequate knowledge regarding birth spacing.
Literature suggests that the prevalence of adverse pregnancy outcomes, including child mortality, is relatively high in the Sylhet division and low in the Rajshahi and Khulna divisions 46,47 and are aligned with the SBI hot spots and cold spots, respectively. There seems to be a two-way relationship between adverse pregnancy outcomes and SBI; adverse outcomes occur due to a relatively high number of births in shorter intervals and vice versa. Findings from the studies in other settings of LIMCs 48–50 demonstrate relatively high birth intervals among couples with fewer children. Couples experiencing the death of a child or even witnessing such an event among the neighbours, are usually motivated to take another child considering the uncertainty, often in a shorter interval 49. Similarly, women who are not engaged in formal jobs are likely to take babies in short intervals 15.
The findings of this study highlight the need for tailored programs in Bangladesh in general and the Sylhet division in particular to reduce the prevalence of SBI. Strengthening reproductive healthcare service delivery, including intrapartum, delivery, postpartum, and postpartum contraceptive services should be prioritized. Providing integrated reproductive healthcare services may help improve the current service delivery. Also, tailoring service modality considering the divisional level barriers is needed 36, as it is not possible in the current uniform top-down policy approach 35,36.
As far we know, this is the first study that explored the hot spots and cold spots of SBI and its associated factors in Bangladesh. The explanatory variables considered in this study were chosen based on a comprehensive review of the existing literature and finally by following the proper statistical model building techniques. The data were collected from two nationally representative surveys conducted in the same year using validated questionnaires. However, the analysis of cross-sectional data means that the findings are correlational only. To ensure the privacy of the respondents, the BDHS displaced cluster locations that we used in plotting our results in maps, up to five km in rural and two km in urban areas. Thus, the areas plotted in the maps as SBI hot spots or cold spots are slightly different from the actual areas from where data were collected, although divisions of data collection were the same. However, the findings are still valid as our results only highlight the potential areas of SBI hot spots or cold spots. Moreover, besides the socio-demographic factors included in this study, area level and environmental factors could also be important predictors of SBI hot spots and cold spots in Bangladesh, but we could not consider those variables in our analysis as they were not available. However, our adjusted variables explained around 65% of the total occurrences of SBI hot spots and cold spots.