Knowledge Brief Health, Nutrition and Population Global Practice EARLY CHILDBIRTH AND UNDER-FIVE MALNUTRITION IN THE REPUBLIC OF THE CONGO Adenike Onagoruwa and Quentin Wodon June 2017 Child Marriage Series with Education Global Practice KEY MESSAGES:  In the Republic of the Congo, more than two in ten children under the age of five are stunted; but for children born of mothers younger than 18, the risk of stunting is higher.  Controlling for socio-economic and other characteristics, being born of a mother younger than 18 does not lead to a statistically significant increase in the likelihood of stunting for children under- five, as compared to otherwise similar children born of older mothers. Nearly one-fifth of under-five deaths could be prevented Box 1: Brief and Series Primer with optimal feeding. Poor nutrition at a young age may How is early childbirth defined? Early childbirth is defined in also have irremediable consequences for brain this brief as a child being born of a mother younger than 18. Early development, cognitive skills, and productivity in adult life. childbearing is related to the practice of child marriage. Malnutrition has severe consequences for children. Why a series on child marriage? Child marriage has significant negative impacts – not only for girls, but also for a range of Poor nutrition weakens children’s immune systems, putting development outcomes. Demonstrating these impacts will assist governments and others to make the case for intervening to them at a greater risk of falling sick from preventable reduce the practice. illnesses such as pneumonia and diarrhea. According to Horton et al. (2008), nearly one-fifth of under-five deaths in What are the topics discussed in the series? The series looks the world could be prevented with optimal feeding. at the impacts of child marriage on health, population, education, Research also suggests that poor nutrition at a young age employment, agency, and violence, among other outcomes. The may have irremediable consequences for brain welfare, budget, and non-monetary costs of child marriage are development, cognitive skills, and ultimately productivity in estimated. Legal/institutional aspects and options to reduce the adult life. Unfortunately, a large share of children in the practice are also discussed. developing world are malnourished. The question What is the question asked in this brief? The question is: What considered in this brief is whether early childbirth (defined is the impact at the margin of an early childbirth on the probability as a child being born of a mother younger than 18), which of malnutrition (stunting) for children under-five years of age? in many countries is the result of child marriage, contributes to under-five malnutrition in a significant way in the How is the question answered? Econometric analysis of Republic of the Congo. The brief is part of a series of similar Demographic and Health Survey data is used to estimate the standardized country-specific briefs on the same topic for impact of an early childbirth on under-five malnutrition. a number of countries. Page 1 HNPGP Knowledge Brief  Statistically, children from young mothers in the Table 2 provides key results with baseline and extended Republic of the Congo are eight percentage points models. The interpretation of the coefficients is in terms of more likely to be stunted than if the mother is between marginal impacts in percentage terms. For example, a 18 and 34 years of age. statistically significant coefficient of 0.05 for a mother younger than 18 would indicate that children of very young The focus in this brief is on stunting as a measure of mothers have a likelihood of stunting five percentage points persistent exposure to malnutrition with potentially severe higher than otherwise similar children of older mothers. long-term consequences throughout a person’s life (see box 2 on indicators used to measure malnutrition). The With the baseline specification, table 2 indicates that analysis is based on data from the 2011-2012 deliveries at a young age do not significantly increase the Demographic and Health Survey for the Republic of the likelihood of stunting for the children in comparison to a Congo. Estimates suggest that 30.32 percent of children delivery at 18 to 34 years of age (in the Republic of the born of mothers younger than 18 are stunted. The Congo). The difference in risk of stunting between mothers proportion is still high, but eight points lower at 22.58 ages 18-34 and mothers above 35 is however statistically percent for children born of mothers 18 to 34 years of age. significant. The difference in stunting rate between these two age groups is statistically significant. For children of mothers In the Republic of the Congo, delivery at a young age does older than 35, the incidence of stunting was also lower at not increase the likelihood of stunting for the child in 21.89 percent. comparison to a delivery at 18 to 34 years of age. Table 1: Incidence of Stunting by Age of the Mother Age of the mother Stunting (%) Marginal effects do not change much when additional Mother younger than 18 30.32 controls are added (extended model). There is thus some Mother in 18-34 age bracket 22.58 evidence that in the case of the Republic of the Congo, Mother older than 35 21.89 after controlling for a wide range of other variables, early Source: Authors. childbirth may not contribute to stunting, but prudence remains needed when interpreting these results given the Box 2: Measures of Malnutrition risk of omitted variable bias (see box 3). Three main measures of malnutrition are used in applied work. A Table 2: Impact of Early Childbirth on Stunting child is considered underweight if s/he has a weight more than Age at first marriage Baseline Extended two standard deviations below the reference median weight for model model the child’s age. A child is considered wasted if s/he has a weight Mother younger than 18 0.0677 0.0462 to height ratio more than two standard deviations below the Mother in 18-34 age bracket Reference Reference median weight for height for the reference population. A child is Mother older than 35 -0.0709*** -0.0767*** considered stunted if s/he has a height more than two standard Source: Authors. deviations below the median reference height for that age. If a Levels of statistical significance: *** 1%, ** 5%, * 10%. child on any of these measures is below three standard deviations of the norm, s/he is considered as severely underweight, wasted, or stunted. Among the three measures, stunting and wasting tend Box 3: Risk of Omitted Variable Bias to be used the most. Stunting often results from persistent insufficient nutrient intake and infections. It may lead to delayed In many countries, although not in the Republic of the Congo, motor development and poor cognitive skills that can affect school early childbirth appears to be positively correlated with the risk of performance as well as productivity and earnings later in life. stunting after controlling for other factors that may also contribute Wasting tends to result more from acute food shortage or disease to stunting. This could indicate a causal effect. However, other and may lead to death. For the purpose of this brief, given a variables correlated with both early childbirth and stunting not separate brief of under-five mortality, stunting is the best measure included in the analysis could be at the source of the correlation to focus on. between early childbirth and stunting. Because of the risk of omitted variable bias, the results cannot be considered as fully conclusive regarding a causal impact of early childbirth on the risk Controlling for other factors, early childbirth does not of stunting. increase the likelihood of stunting substantially. A number of results from the regression analysis not shown The difference in the likelihood of stunting between children in table 2 are worth mentioning. The impact of wealth on of young and older mothers does not necessarily imply a the likelihood of stunting is statistically significant in the two causal effect of the age at delivery, but it does suggest that highest wealth quintiles. For example, children in the early childbirth may contribute to stunting. To check highest quintile (the richest 20% of households) have a whether controlling for other factors early childbirth is likelihood of stunting sixteen percentage points lower than associated at the margin with higher under-five children in the poorest 20% of households. This is not malnutrition, regression analysis is used (see the annex for surprising, and could be due to the fact that households in details on the methodology). the bottom quintiles are poor or near poor in a country like Page 2 the Republic of the Congo. Given that the incidence of stunting is so high, whether a household is extremely poor, Because only a small share of deliveries are by mothers or simply poor, does not make much of a difference on the younger than 18, very few stunted children can be said to likelihood that children will be stunted. be stunted directly due to early childbirth. As shown in table 3, the marginal impact of a mother having Conclusion a secondary education or better on the likelihood that her child will be stunted is not statistically significant, which is Early childbirth may contribute to the risk of malnutrition for somewhat surprising. children, directly and indirectly. This brief has provided Note though more generally that the inclusion of education estimates of the direct impact of early childbirth on stunting in the Republic of the Congo using the latest DHS survey. as a control points to the possibility of indirect effects of More than two in ten children under the age of five are early childbirth on stunting. Because early childbirth may stunted. Controlling for socio-economic and other have an impact on other variables used as controls in the characteristics, being born of a mother younger than 18 regression, its overall effect on stunting, including indirect effects through these other variables, may be larger than does not have a statistically significant effect on the the (non-significant) direct effect documented in table 2. likelihood of stunting as compared to otherwise similar children born of older mothers. This, together with small For example, for some girls having a baby at a young age, indirect effects of early childbirth through education in the early childbirth could have reduced education attainment, Republic of the Congo, suggests that few children are which could lead to a higher risk of stunting (although not stunted directly or indirectly because of an early childbirth, in the Republic of the Congo according to the regression results). In addition, early deliveries, by increasing the even though some may be. number of household members may also contribute to References lower standards of living. In the Republic of the Congo, as mentioned earlier, the regression results suggest that the Centre Nationale de la Statistique et des Études Économiques level of welfare as measured through wealth quintiles have (CNSEE) [Congo] et ICF International (2013). Enquête an effect on stunting. Démographique et de Santé du Congo (EDSC-II) 2011-2012. Calverton, Maryland, USA : CNSEE et ICF International. Early childbirth may affect under-five malnutrition through lower education attainment for mothers or lower socio- Fall, C. H., et al., 2015, Association between maternal age at childbirth and child and adult outcomes in the offspring: a economic status. prospective study in five low-income and middle-income countries (COHORTS collaboration), Lancet Glob Health 3(7):e366-77. Table 3: Impact of the Mother’s Education on Stunting Age at first marriage Baseline Extended Finlay. J. E., E. Özaltin, and D. Canning, 2011, The association model model of maternal age with infant mortality, child anthropometric failure, No education or below primary Reference Reference diarrhoea and anaemia for first births: evidence from 55 low- and Primary education 0.0234 0.0185 middle-income countries, BMJ 1:e000226. Secondary education or higher -0.00468 -0.00146 Source: Authors. Horton, S., H. Alderman, and J. Rivera. 2008. “Copenhagen Levels of statistical significance: *** 1%, ** 5%, * 10%. Consensus 2008 Challenge Paper: Hunger and Malnutrition.” http://www.copenhagenconsensus.com. Simulations suggest that very few children under-five are stunted directly due to early childbirth. The last step in the analysis consists in assessing the potential impact of eliminating early childbirth on stunting. This can be done by predicting (i.e. simulating) the likelihood that children who were born of mothers younger than 18 would have been stunted if they had been born of older mothers. In other words, we are considering the direct effects of the age of the mother on stunting, shifting in the data deliveries by young mothers to deliveries at a later age, and observing the difference that this makes for stunting rates nationally. In the case of the Republic of the Congo, because the effect of early childbirth on stunting is not statistically significant, direct effects are not (statistically speaking) present. Page 3 HNPGP Knowledge Brief  Annex: Methodological Note In this brief, due to space constraints and because of the interest There is an existing literature on the relationships between early in the share of stunting that could be attributed to early childbirth, childbirth, child marriage, and the risks of under-five malnutrition the focus is on reporting results from probit regressions. In those (e.g., Fall et al., 2015, and Finlay et al. 2011). This literature regressions, the dependent variable is whether a child is stunted suggests that children born of young mothers are at higher risk of or not. malnutrition. How much higher in the case of Niger is the question to be answered. To answer this question, this brief focuses on Different specifications are estimated to assess the robustness of stunting as the measure that tends to best capture persistent the results to the choice of models. Overall, the results are fairly exposure to malnutrition with likely long term negative robust to different specifications. For the baseline model, the consequences for children. independent variables are the following: (1) the age of the mother at the time of delivery by categories; (2) the child’s age and There is no doubt that children born to very young mothers are gender; (3) whether the child had siblings born at the same time more likely to be malnourished than other children, but this might (multiple birth); (4) the birth order of the child and the child’s birth not specifically be due to the fact that the mothers are young. Girls weight by categories; (5) the length of time between the child’s who have children before the age of 18 tend to be poorer. This birth and a previous birth for the mother; (6) whether the child has implies that their children are at higher risk of inadequate received recommended immunizations; (7) whether the delivery nutritional intake. Early pregnancies are more common in areas took place in a health facility and was attended by skilled where access to healthcare is limited to prevent or treat personnel; (8) the mother’s height and education level, as well as malnutrition. Young girls also often suffer from a lack of agency whether she works and the type of work involved; (9) the father’s and decision-making power in the household, which may reduce occupation and his level of education; (10) the location of the child their ability to seek care for their children when needed. Girls who by region and by urban-rural category; (11) whether the give birth early are likely to have dropped out of school due to household has access to an improved water source and improved pregnancy or marriage, which may also affects the nutritional sanitation; (12) whether the household has more than two status of their children due to lack of education or knowledge on children under-five; and finally (13) the wealth quintile of the how to best take care of young children. household. These risk factors correlated with early childbirth do not In the extended model, additional controls are added: (14) necessarily imply that early pregnancies by themselves contribute whether the household practices polygyny; (15) whether the in a direct way to child malnutrition. Controlling for other factors, distance to health facility is a major problem for the household; it could be that early childbirth does not lead to a higher risk of (16) the age gap between the spouses; (17) indicators of malnutrition for children. But it could also be that there is a direct decision-making power for the mother; (19) tolerance towards causal link between early childbirth and child malnutrition, for wife beating; and (20) whether the mother is able to get example if some young mothers giving birth are not yet be ready permission to access healthcare. physiologically to give birth, which could in turn affect the health of their children. This brief estimates the direct impact of early This brief was produced by a World Bank team as part of the Economic childbirth on under-five malnutrition. Impacts of Child Marriage study. The synthesis report under the study was produced jointly with the International Center for Research on Women. In addition, the brief provides an assessment of the extent to The study benefitted from support from the Bill & Melinda Gates which under-five malnutrition would be reduced if early Foundation, the Children’s Investment Fund Foundation, and the Global pregnancies/deliveries were eliminated. In order to measure the Partnership for Education. Comments from colleagues and peer potential impact of early childbirth at the margin on stunting for reviewers are gratefully acknowledged. The opinions expressed in this brief are those of the authors only and need not reflect the views of the children under the age of five, regression analysis is used. In the World Bank, its Executive Directors, of the countries they represent. more detailed paper on which this brief is based, both tobit regressions (to measure the degree of stunting among children who are stunted) and probit regressions (to measure the likelihood of stunting) are provided. The Health, Nutrition and Population Knowledge Briefs of the World Bank are a quick reference on the essentials of specific HNP-related topics summarizing new findings and information. These may highlight an issue and key interventions proven to be effective in improving health, or disseminate new findings and lessons learned from the regions. For more information on this topic, go to: www.worldbank.org/health. Page 4