Caesarean delivery and its association with educational attainment, wealth index, and place of residence in Sub-Saharan Africa: a meta-analysis

Caesarean delivery (C-section) has been increasing worldwide; however, many women from developing countries in Sub-Saharan Africa are deprived of these lifesaving services. This study aimed to explore the impact of certain socioeconomic factors, including respondent’s education, husband’s education, place of residence, and wealth index, on C-section delivery for women in Sub-Saharan Africa. We used pooled data from 36 demographic and health surveys (DHS) in Sub-Saharan Africa. Married women aged 15–49 years who have at least one child in the last five years were considered in this survey. After inclusion and excluding criteria, 234,660 participants were eligible for final analysis. Binary logistic regression was executed to determine the effects of selected socioeconomic factors. The countries were assembled into four sub-regions (Southern Africa, West Africa, East Africa, and Central Africa), and a meta-analysis was conducted. We performed random-effects model estimation for meta-analysis to assess the overall effects and consistency between covariates and utilization of C-section delivery as substantial heterogeneity was identified (I2 > 50%). Furthermore, the meta-regression was carried out to explain the additional amount of heterogeneity by country levels. We performed a sensitivity analysis to examine the effects of outliers in this study. Findings suggest that less than 15% of women in many Sub-Saharan African countries had C-section delivery. Maternal education (OR 4.12; CI 3.75, 4.51), wealth index (OR 2.05; CI 1.94, 2.17), paternal education (OR 1.71; CI 1.57, 1.86), and place of residence (OR 1.51; CI 1.44, 1.58) were significantly associated with the utilization of C-section delivery. These results were also consistent in sub-regional meta-analyses. The meta-regression suggests that the total percentage of births attended by skilled health staff (TPBASHS) has a significant inverse association with C-section utilization regarding educational attainment (respondent & husband), place of residence, and wealth index. The data structure was restricted to define the distinction between elective and emergency c-sections. It is essential to provide an appropriate lifesaving mechanism, such as C-section delivery opportunities, through proper facilities for rural, uneducated, impoverished Sub-Saharan African women to minimize both maternal and infant mortality.

We screened all the data set from SSA countries. We selected the data set from 2006 to 2021. We excluded 03 more countries before 2006. Finally, we have selected 36 SSA countries, where similar probability sampling was applied for data collection 33 (Fig. 1). After excluding the missing cases, the participants from 36 SSA countries have been included in the study.
Variables. The participants of this study were women who chose the C-section as delivery mode during their delivery; therefore, C-section delivery is the response variable. This response variable was categorized into two groups: those who had at least one C-section delivery were considered category 'Yes'; those with no C-section were classified as 'No' . For the logistic regression model, the independent variables include maternal education, paternal education, wealth index, place of residence. The categories of the place of residence ('rural' , 'urban'), respondent's education ('No education' , 'Primary' , 'Secondary' , 'Higher') and husband's education ('No education' , 'Primary' , 'Secondary' , 'Higher') remain same as it was in the BDHS data set. For the variable wealth index, were categorized it by adding poorer and poor to 'poor' , middle as middle and rich, and richest to 'rich' . For the meta-analysis, we categorized parental education, including paternal and maternal, as 'Educated' , merging primary, secondary, and higher education, and 'Not educated' , including the not educated individuals. Wealth index was formulated into 'Up to middle' merging the poorest, poorer, and middle, whereas 'Rich' was www.nature.com/scientificreports/ constructed by combining richer and the richest. Place of residence the categories remained the same as it was found in the original dataset as rural and urban.
Moderator. Birth by skilled health staff is recommended by healthcare centres worldwide for a healthy pregnancy period and childbirth. Renowned health organizations train the health staff to ensure safe and convenient delivery 34 . As a result, these attendants could appropriately assess the delivery mode and provide pregnancyrelated awareness throughout gestation. More precisely, they have superior knowledge of dietary intake and subsequent pregnancy-related complications and treatments, enabling them to avoid various health risks. They directly affect childbirth mode, pregnancy care, and pregnancy-related consciousness 34 . Besides, the total percentage of births attended by skilled health staff (TPBASHS) of a country could be utilized to estimate the effect size and identify additional sources of heterogeneity between C-section delivery and socioeconomic variables; however, meta-regression is scarce on this dimension.
Ethics declarations. The secondary source named Demographic Health Survey (DHS) was utilized to obtain the dataset. The only participant of the DHS program is human. We have got permission from https:// dhspr ogram. com/ to use the data through strict instructions and data confidentiality assurance. The DHS program has followed Helsinki Declaration (1964) ethical standards to assure ethical approval for each survey. The survey report from its website illustrates the entire survey information, including participants' selection, sample size determination, ethical approval, sampling procedure, etc.
Consent to participate. Each selected participant in the survey sampling was sent an informed consent before beginning the interview. It is because of ensuring participants' authorization and confidentiality in the survey.
Statistical analysis. We used statistical software SPSS V.23 (SPSS Inc. Chicago, USA) and R V.3.6.2 (Bell Laboratories, New Jersey, USA) to carry out the analysis. Binary logistic regression was executed using the key factors that impact C-section delivery using pooled data of 36 Sub-Saharan African countries 35,36 . We also applied meta-analysis techniques on the 36 DHS data from Sub -Saharan Africa 37 . Heterogeneity was assessed by enumerating values from I 2 and p values among datasets 38,39 . We performed a random-effects model in the meta-analytical approach as significant heterogeneity was found by which we estimated DerSimonian and Laird's pooled effect 40,41 . The 'leave-one-out' sensitivity analysis was conducted to determine the effect of heterogeneity and outliers 42 . Forest plots were used to display 95% confidence interval (CI), 95% prediction interval, summary measure, and weight of each study for the most significant determinants 43 . The 95% prediction interval is used to estimate ranges that will define the expected effects for 95% of further studies. Subgroup analyses were applied to find out the regional difference of the influencing factors of C-section delivery across SSA countries. Further, the authors deployed random-effects meta-regression with the total percentage of births attended by skilled health staff (TPBASHS) as a moderator in order to detect an extra amount of heterogeneity between C-section and socioeconomic variables, including education, place of residence, and wealth index. Test of moderator was performed by meta-regression to identify the significant influence of the moderator on effect size. The study is presented findings of meta-regression through scatterplot, executing in R Studio version 4.0.5. This study used 'leave-one-country-out' sensitivity analysis to assess the stability of the results and to examine whether one country had an excessive impact on the meta-analysis 44 . As a summary measure, we used Odds Ratio (OR), and all findings were weighted to handle bias due to under sampling and oversampling.
Patient and public involvement. We have used nationally representative Demographic and Health Survey (DHS) secondary data sets. for Sub-Saharan African countries, which were collected following rigorous rules by the authorities. That is why any kind of patient and public involvement was not applicable for this study. Table 1 shows the baseline characteristics for selected variables of 36 Sub-Saharan African countries. The proportion of delivery by caesarean section was lowest in Chad (1.3%); on the other hand, it was highest (24.5%) in South Africa among all countries. Table 2 shows that the respondent from an urban area is 1.51 (OR 1.51; CI 1.44, 1.58) times more likely to use C-section delivery than the respondents forms rural areas. Respondents with high education were 4.12 times (OR 4.12; CI 3.75, 4.51) more likely to use C-section delivery than the respondents with no education. A respondent with a higher educated husband was 1.71 times (OR 1.71; CI 1.57, 1.86) more likely to use C-section delivery than the respondent with a not educated husband. A wealthy family respondent was 2.05 times (OR 2.05; CI 1.94, 2.17) more likely to use C-section delivery than a respondent from a low-income family.

Results
Our study used the random-effects model as the study showed high between-study variations (heterogeneity). Table 3 shows the results of random effect model estimation results of 36 Sub-Saharan African countries, and Table 4 shows the summary effect of different explanatory variables. For respondent's education, the overall OR was 2.55 (95% CI 2.14 to 3.05; p ≤ 0.0001; 95% PI: 0.94 to 6.95), meaning the educated respondents were 155% more likely to use caesarian section delivery than the illiterate respondents. About 85.5% of the variation (I 2 = 85.5%) was found for this variable. For husband's education, the overall OR was 2.41 (95% CI 2.00 to 2.90; p ≤ 0.0001; 95% PI: 0.84 to 6.92), meaning the respondents with educated husbands were 141% more likely to use C-section delivery than the respondents with illiterate husband (I 2 = 89.3%). For the place of residence, the overall OR was 3. 21  www.nature.com/scientificreports/ C-section delivery was 221% higher to the individuals who came from urban areas compared to those who were from rural settings (I 2 90.8%,). For wealth index, I 2 was 87.8%, where the overall OR was 3.31 (95% CI 2.89 to 3.77; p ≤ 0.0001; 95% PI: 1.52 to 7.20), which reveals that the utilization of C-section delivery was 231% higher for the individuals from rich families compared to the respondents from low-income families. Table 5 and Fig. 2 show that place of residence significantly affected the C-section delivery concerning the region in SSA countries. For instance, women who lived in urban areas were more likely to utilize C-section delivery in the East Africa region (OR 3.56, p < 0.01, I 2 = 94%) than the other regions of SSA countries. Figure 3 and Table 5 show that the respondents from a rich family background were more likely to take C-section delivery. The West Africa region has the highest tendency of C-section (OR 3.66, p < 0.01, I 2 = 87%) than the other SSA regions. Figure 4 indicates that the respondent's education significantly influenced the C-section delivery in SSA countries. For instance, educated women were more likely to utilize C-section delivery in the East Africa region (OR 2.65, p < 0.01, I 2 = 84%) than the other regions of SSA countries. In Fig. 5, it is clear that the husband's education significantly influenced the utilization of C-sections across the SSA countries. Results indicated that the respondents with educated husbands were more prone to use C-section delivery in West Africa (OR 2.71, < 0.01, I 2 = 91%). www.nature.com/scientificreports/ Tests of moderator for educational attainment, residence, and wealth index are exhibited in Table 6. The findings reveal that these tests are statistically significant for all socioeconomic variables. Consequently, TPBASHS has a significant influence on the countries' effect size and could significantly explain the extra amount of heterogeneity for all four variables. Figure 6 shows the odds of C-section utilization to determine the influence of TPBASHS in all 36 countries from the Sub-Saharan African sub-continent. A significant negative association is observed between TPBASHS and C-section delivery for all four socioeconomic variables. For respondent educational attainment and accommodation, the estimated value of TPBASHS were -0.0160 (95% CI − 0.0233 to − 0.0087; R 2 = 41.75%) and − 0.0181 (95% CI − 0.0240 to − 0.0122; R 2 = 46.44%). The findings also include that 41.75% (respondent education) and 46.44% (place of residence) of variation in true effect sizes could be explained by TPBASHS.

Discussion
Over past decades, an uncertain increase in C-section rate is occurring. Education, wealth, and residence were strongly associated with the utilization of C-section in the SSA regions. The current study was more informative in providing the rate and association of C-section delivery with education, wealth, and place of residence as compared to that of previous findings. In the current study, the highest caesarean rate was found in Latin America and the Caribbean regions (40.5%), followed by Northern America (32.3%), Oceania (31.1%), Europe (25%), Asia (19.2%), and Africa (7.3%). This trend is increasing worldwide, especially in Egypt, Turkey, Dominican Republic, Georgia, and China, except for two countries (Guinea and Nigeria). The C-section rate decreased in Zimbabwe. These different rates of C-section in different countries showed that it was varying widely among the SSA countries, while WHO recommends that it should be 5-15% 45 . Dikete et al. reported that C-section rate in sub-Saharan Africa was 14 to 24%, which showed variation from the current study 46 . Bonsaffoh et al. reported a higher level of C-section rate i.e., 46%, as compared to current findings 47 . Betran et al. reported a study similar to the present finding in which 18.6% of all births occurred by C-section. In that previous finding, the highest caesarean rate was in Latin America, Caribbean regions, and Northern America (42.9%) followed by northern Africa (27.8%), Africa (7.3%), Saharan Africa (3.5%). Sanni et al. reported a study dissimilar to the present study in which the public health care centres rate of C-section was 3% in Burana and 15.6% in Ghana. While the private health care centers were having a C-section rate of 0% and 64% in Sao tome and Rwanda 48 .
A metanalysis on 36 different countries of sub-Saharan showed that 41.75%, 18.11%, 46.44%, and 36.35% of the C-section deliveries occur due to respondent education, husband education, place of residence, and wealth index, respectively. The BLR model and meta-analysis revealed that parents' education is a crucial factor that is the reason behind the increased rate of C-sections. Educated respondents are more likely to use C-section delivery compared to respondents with no education. Regarding the association of C-section rate with education, the current study showed similarity with many of the previous studies except a few ones. Majid et al. (2019) presented a study in Iran that showed that the probability of utilizing the C-section is higher among educated women than women having lower education 49    www.nature.com/scientificreports/ women make their own decision regarding delivery, and they, in general, prefer C-section delivery [50][51][52][53] . However, previous findings of Epistein et al., Lee et al., and Mumtaz et al. reported that the educated women prefer C-section as the level of pain is lower, and they believe it is safer and interferes less with the workload, leisure time, and socially more prestigious than the normal vaginal delivery 49,54,55 . Another study by Long et al. (2015) showed that the overall OR for paternal education also showed that husbands with education are more likely to use C-section delivery than husbands with no education. The result delivered a similar statement from the BLR model and was consistent with previous studies 56 . A study reported by Bandori et al. showed exception. It showed that high education is not always positively associated with the likelihood of having the C-section. Therefore, in South Korea, the negative association between education and C-section rate has also been seen in the literature. The reason for this exception is that the education is also providing information on health-promoting behaviour, more educated women have more knowledge about the risk of unnecessary C-sections [57][58][59] . The second determent highlighted by this study was the place of residence that plays an essential role in the increased C-section rate. The utilization of C-section delivery is higher to individuals from urban areas, whereas the rate is comparatively lower to individuals from rural settings. Similar to the current study, a previous www.nature.com/scientificreports/ study reported by Bahadori et al. (2013) showed that the women from rural areas had less chance to utilize the C-section delivery than women from urban areas 57 . Another study showed similarity with the current study by describing the prevalence of C-sections rates ranging from 4.6% to 12.2% for urban areas, whereas the prevalence of C-section rate ranging from 1.6% to 3.9% for rural areas 60 . The findings of this study are also in line with the previous studies, which suggest that the prevalence of C-sections in urban areas is significantly higher than those in rural areas. Maybe women who live in rural areas have fewer delivery mode options, awareness, and limited financial resources 58,61,62 . Based on 80 demographic and health surveys conducted in 26 countries in Southern Asia and SSA, a study reported by Cavallaro et al. (2013) revealed that women from urban areas were more likely to utilize the C-section delivery than rural women 59 . Availability, accessibility, and affordability of C-sections in urban areas women are more than the rural women, more private C-section facilities and higher women employment rate in urban areas could be the reasons behind the high caesarean rate in urban areas compared to rural areas 63,64 . Wealth status is another determinant of increased C-section. Wealthy families utilize C-sections more than low-income families, which is in line with current findings. Previous studies reported that the C-section tendency is more among women with a wealthy family background than women with low-income family background 55,[65][66][67] , and the other study reveals that 12.3% of the rich women had a C-sections delivery compared to 1.7% of the poor women 60 . Different studies suggested that poor women in the developing world cannot afford this lifesaving procedure and give birth at home, which is another reason for wealthy family women's high caesarean delivery in SSA 48,68,69 . A data analysis based on over 20,000 births shows that women of higher socioeconomic backgrounds who had better access to antenatal services are the most likely to undergo a C-section 70 . However, the opposite trend has also been observed in developed countries, where higher education and economic status were protective against C-sections as awareness and knowledge of childbirth are expected to be high among this group of women 71 . Strength and limitation. This study used a large sample size involving multiple nationally representative datasets from 36 countries in SSA to investigate the prevalence of C-sections in the sub-Sahara Africa region. We combined two methods: binary logistic regression and meta-analysis of 36 DHS data of Sub-Saharan African countries. The integrated findings enlarged the validity of the outcome of the research. We unfolded a new research approach by introducing this mixed-method design. Because of its extensive and acute quality, better knowledge and insights could be generated. Also, we applied subgroup analysis to find out the regional effect. www.nature.com/scientificreports/ Nonetheless, the data lacks information relating to clinical indications for C-sections, as the data did not distinguish between elective and emergency C-sections. Also, the use of this information for decision-making and comparison should consider the cross-sectional nature of the data, which is inadequate to sufficiently establish causality. Another limitation is that for estimating OR from random-effects meta-analysis, we had to create 2 × 2 cross-tabulation for which each variable was categorized into two categories only. Moreover, a vast number of factors that could influence C-sections could not be included in our study because the DHS has very limited information on both supply-and demand-side variables regarding C-section.

Conclusion
The findings from the present study show that educated women and husbands, women residing in the urban area, and the wealthiest households are more likely to utilize C-section delivery in the Sub-Saharan region. Additionally, the higher percentage of births attended by skilled health staff of a country can significantly reduce the C-section delivery for variables educational attainment (respondent & husband), place of residence, and wealth index, exhibited by meta-regression. Although maternal, neonatal, and infant mortality and morbidity can be influenced by unnecessary C-sections, it can save women and their new-born lives in case of life-threatening pregnancy and childbirth-related complications. Therefore, our results suggest that strategies are needed to provide C-sections through proper facilities for rural, uneducated, impoverished Sub-Saharan African women to minimize maternal and infant mortality so that they can get access to the lifesaving procedure when necessary. Furthermore, the significant role of skilled health staff in the delivery period must be illustrated among pregnant women by health-related programs in each Sub-Saharan African country.