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THE DETERMINANTS OF BIRTHWEIGHT IN UGANDA

Lawrence Bategeka (Team Leader)

Economic Policy Research Centre, Kampala, Uganda

E-Mail: bategeka@eprc.or.ug

Margret Leah Okurut Asekenye,

Department of Gender, Makerere University

E-Mail: asekenyel@yahoo.co.uk

Mildred Barungi, Kampala

Joy Musiime Apolot, Kampala

A Final Report Submitted to AERC, Nairobi, Kenya

.

January, 2009

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Abstract

The study had two distinctive components, namely, the quantitative and qualitative. The

quantitative study investigated the factors that influence birth weight in Uganda using

instrumental variable (2SLS) model. The study used the Uganda Demographic Health Survey

(UDHS) data for 2006 collected by Uganda Bureau of Statistics (UBOS). The findings suggest

that birth weight is positively and significantly influenced by the mother’s tetanus immunization

status, education level, and antenatal care, but negatively influenced by mother’s smoking of

cigarettes/tobacco and malaria infection.

The qualitative study investigated the relationship between reproductive health services and

household welfare. Specifically it examined how utilization of reproductive health services

improves the health status for the mother and child, additional time created as a result of

improved health, the utilization of that time in economic activities to alleviate poverty. The

findings suggest that the use of reproductive health services results in improved health status of

the mother and child and creation of additional time. However the utilization of this additional

time on productive economic activities by women is constrained by lack of access to credit, the

gender division of labour, and excessive taxation on small businesses.

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1. Introduction

1.1 Governance and Economic Growth

Uganda has a decentralized system of governance and several functions have been devolved to the

local governments. However, the central government retains the role of policy making, setting

standards and supervising.

Following independence in 1962, Uganda had a flourishing economy with a gross domestic

product (GDP) growth rate of 5 percent per annum, compared with a population growth rate of

2.6 percent per annum for the period 1962 to 1970. However, in the 1970’s through early 1980’s,

Uganda faced a period of civil and military unrest, resulting in the destruction of economic and

social infrastructure. Since 1986, however, the government introduced and implemented several

reform programs that have steadily reversed the setbacks and propelled the country towards

economic prosperity. Between 2001 and 2006, the country’s rate of GDP growth rate varied

between 4.7 percent and 6.6 percent per annum (UBOS, 2006)

1.2 Poverty Trends

Restoration of macroeconomic stability in the early 1990s paved way for policy focus on poverty

reduction via the implementation of the Poverty Eradication Action Plan (PEAP). To ensure that

the PEAP is relevant to changing development environments, it is revised every three years to

incorporate new policy responses to emerging challenges. To provide reliable databases for

monitoring poverty reduction progress, the government operates long-term participatory poverty

assessment and national household survey programs. The household survey data have been

analyzed intensively by scholars to demonstrate that the recovery and growth strategies of the

1990s yielded impressive poverty reduction impact. (Okidi et al, 2005)

The headcount index of total income poverty declined from 56% in 1992 (corresponding to 9.2

million persons, in absolute numbers) to 34% (corresponding to 7.2 million persons) in 2000, after

which it rose to 38% (corresponding to 8.9 million persons) in 2003 (Appleton et al., 1999;

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Appleton and Ssewanyana, 2003). However, poverty in Uganda remains a rural phenomenon and

more pronounced among crop farmers. Rural poverty headcount declined from 60% in 1992 to

37% in 2000 before rising to 42% in 2003. The corresponding figures for urban areas are 28, 10

and 12 percent. The disproportionate contribution of rural areas to the national poverty has

remained unchanged at about 96%. Regional imbalance, especially between Northern and the rest

of the country, has persisted, with Northern being the only region where consumption expenditure

declined between 1997 and 2000. Although between 2000 and 2003 the poverty headcount in

Northern remained about the same while it was rising for the rest of the country, this region has

maintained the highest incidence of poverty of not less than 64%. Regarding income groups, the

growth incidence that disproportionately favored the lower end of the income distribution in the

early 1990s was reversed in the recent years when welfare growth was confined to the richest 20%

of Ugandans while the rest of the population reported a decline in consumption expenditure. This

translated into the reported increase in poverty and the rise in welfare inequality from a Gini

coefficient of 0.40 in 1999/2000 to 0.43 in 2002/2003 (Appleton et al., 1999; Appleton and

Ssewanyana, 2003).

1.3 Demographic Indicators of the Population

The demographic indices compiled from the population census 1969 through to 2002 are

presented in table 1. The population more that doubled for the period 1969 to 2002, rising from

9.5 million to 24.2 million. The annual population growth rate between 1969 and 1980 was 2.7

percent, but decreased to 2.5 percent between 1980 and 1991 and later increased to 3.2 percent

between 1991 and 2002. The high growth rate was attributed to the high fertility rate and

declining mortality levels. The level of urbanization is low but increasing over time, rising from

6.6 percent in 1969 to 12.3 percent in 2002. The overall life expectancy has also been rising over

time, from 46.5 years in 1969 to 50.4 years in 2002.

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Table 1: Basic Demographic Indicators of the Population Indicator 1969 1980 1991 2002 Population (thousand) 9,535.1 12,632.2 16,672.2 24,227.3 Intercensal growth rate (%) 3.9 2.7 2.5 3.2 Density (Population/km) 48 64 85 124 Percent urban 6.6 6.7 9.9 12.3 Life Expectancy Male 46 na 45.7 48.8 Female 47 na 50.5 52.0 Total 46.5 na 48.1 50.4 na = not available Source: UBOS (2006) Table 1.1 page 2 1.4 National Population and Health Policy

The 1995 National Population Policy was designed with the key objective of integrating the

population and demographic factors at all planning levels, to promote positive health seeking

behavior and reduce the unmet need for family planning. The policy takes into account the

changing demographic, socio-economic and health environment (UBOS, 2006)

The National Health Strategic Plan 2005/06-2009/10 (HSSP 11) priorities to fulfill the health

sector contribution to the Poverty Eradication Action Plan (PEAP) and the Millennium

Development Goals (MDG). The plan emphasizes the role of communities and households and

seeks to foster a sense of individual ownership of health services. The programme targets among

others the poor, children and women (UBOS, 2006).

Following the 1994 International Conference on Population and Development (ICPD), the

Government of Uganda (GOU) developed the Reproductive Health Policy Guidelines. The

guidelines help the GOU and reproductive health service providers to provide safe motherhood

services and reduce the number of maternal-related deaths and improve child health. Other related

policies to population and health that have been implemented by the GOU in collaboration with

development partners include Adolescent Sexual and Reproductive Health Policy, the Nutrition

Policy, the HIV/AIDS Strategic Plan, the Gender Policy, the Poverty Eradication Action Plan, the

National Malaria Control Plan and the New Born Health Strategy. The various population and

reproductive health programmes are aimed at improving health behaviors of the population (CSO,

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2006).

2. The Reproductive health Concept

Reproductive health is the outcome of consumption of both reproductive health care and other

goods and services (Ajakaiye and Mwabu, 2007). The reproductive health indicators include

maternal mortality, infant mortality, total fertility rates, weight at birth and child survival rates. The

key components of reproductive health care include family planning, safe delivery services,

prenatal and postnatal care, treatment of placental malaria, nutrient supplements during pregnancy

and behaviours that promote fetal growth.

The utilization of reproductive health care inputs is constrained by market and non-market factors.

The market factors include availability of reproductive health inputs and their prices, and

household income. The non –market factors include household characteristics (such as rural or

urban location) and individual characteristics [such as age, education, health status, and the

information they posses about the quality of reproductive health care services] (Ajakaiye and

Mwabu, 2007).

This study specifically focuses on birth weight as a measure of reproductive health outcome and

the factors that influence it. The results from this study are instrumental in the design of policies to

improve the provision and consumption of reproductive health care services and thus improve

child health.

2.1 Demand for Reproductive Health Services

The demand behaviour for reproductive health services by a mother will be analyzed using a model

in which the child is embedded in a utility function (Ajakaiye and Mwabu, 2007; Rosenzweig and

Schultz, 1982). The demand for reproductive health care is analyzed within the framework of

utility maximization behaviour of the mother:

U = U(X, Y, H) …………………………………………………………. (1)

Where:

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U = Utility derived from consumption of goods, including reproductive health

X = Health neutral goods that yield utility to a mother but have no direct effect on

reproductive health status of the mother

Y = Health related goods or behaviour that yields utility to the mother and also affects birth

weight

H = Reproductive health status of the child, measured by birth weight

The reproductive health production function is given by:

H = H(Y, Z, μ) ………………………………………………………… (2)

where:

Z = Purchased market inputs such as medical care that affect child health directly

μ = the component of child health due to either genetic or environmental conditions uninfluenced

by behaviour.

The mother maximizes (1) and (2) subject to the budget constraint:

I = XPx + YPy + ZPz ………………………………………………. (3)

where:

I = Exogeneous income

Px, Py and Pz are the prices of health neutral good X (such as clothing); health related consumer

good Y (such as quitting smoking) and health investment good Z (such as tetanus immunization)

respectively.

The health investment goods are purchased only for the purpose of improving the child

reproductive health, so they enter the mother’s utility function only through H. The birth weight

production function (Equation 2) has the property of constrained utility maximization behaviour

of the mother (Equations 1 and 3). Equations 1 – 3 can be re-expressed to yield reproductive

health care demand functions of the form:

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X = Dx(Px, Py, Pz, I, μ) …………………………………………….…….. (4.1)

Y = Dy(Px, Py, Pz, I, μ) …………………………………………….…….. (4.2)

Z = Dz(Px, Py, Pz, I, μ) …………………………………………….…….. (4.3)

The effects of the changes in the prices of the three goods on health input demand can be derived

from equations 4.1 – 4.3 since from equation (2) a change in child health can be expressed as

follows:

dH = FydY + FzdZ + Fμdμ ……………………………………….…….. (5)

where:

Fy , Fz and Fμ are the marginal products of health inputs Y, Z and μ respectively computed as

follows: Fy = δH/δY; Fz = δH/δZ; Fμ = δH/δ μ.

From equation (2), the change in health can be related to changes in respective prices of health

inputs:

dH/dPx = FydY/dPx + FzdZ/dPx + Fμdμ/dPx ……………………………. (6.1)

dH/dPy = FydY/dPy + FzdZ/dPy + Fμdμ/dPy ……………………………. (6.2)

dH/dPz = FydY/dPz + FzdZ/dPz + Fμdμ/dPz ………………………………………. (6.3)

where: dμ/dPi = 0, for i = x, y and z so that the terms Fμ

(.) = 0 in equation (6) as μ is a random

variable unrelated to commodity prices.

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3. Methodology

The study used two techniques: quantitative and qualitative analysis. The quantitative technique

investigated the determinants of birth weight using econometric methods, while the qualitative

approach investigated how reproductive health impacts household welfare. The data sources and

analytical techniques for each of the approaches are discussed below.

3.1 Quantitative Methods

3.1.1 Data and Hypothesized Relationships

The study used Uganda Demographic Health Survey (UDHS) data set for 2006 collected by

Uganda Bureau of Statistics (UBOS). The survey collected data on variables that will be used to

jointly estimate the demand for tetanus immunization and the birth weight production function.

The specific variables include immunization of mothers against tetanus during pregnancy, birth

weight, whether a child was delivered at home or health facility, mother’s education level, father’s

education level, mother’s age, mother’s employment status, household ownership of agricultural

land (used as a proxy for wealth), household access to the media (radio, TV, or newspapers), time

taken by mother to collect water, and location of household (rural/urban).

Child health is measured by birth weight (Rosenzweig and Schultz, 1983). Birth weight is a good

indicator of health of the child in the womb because the weight is taken immediately after birth.

Hence a malnourished fetus will be born at low birth weight. The key determinants of birth weight

include nutritional status and age of the mother, mother’s immunization against preventable

diseases and behavioural change during pregnancy. Other factors such as areas of residence, which

are proxies of availability of health care and nutrients, also affect the health of the child in the

uterus.

Immunization against tetanus during pregnancy is used as a proxy for antenatal care services

received by the mother. Immunization against tetanus is further assumed to be complementary to

other inputs that improve the health of the child in the womb, such as presumptive malaria

treatment and avoidance of risky behaviours (Dow et al, 1999). Tetanus immunization for

pregnant women is one of the major components of the Expanded Program on Immunization

(EPI), a world-wide vaccination initiative sponsored by the World Health Organization, which also

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provides maternal services to women such as safe delivery and post-natal care. In accordance with

complementarity argument, it can be argued that women who received tetanus immunization

during the UDHS 2006 survey were more likely to engage in demand behaviour that increased

birth weight than women who were not immunized. The central argument is not that tetanus

vaccination directly increases birth weight, but that vaccination is strongly correlated with health

care consumption and behaviours that increase birth weight (Ajakaiye and Mwabu, 2007). By

implication, the adoption of a specific behaviour or the uptake of a specific input improves health,

creates incentives to engage in other health-augmenting behaviours or consumption that improve

birth weight.

However, the mother’s immunization against tetanus could also induce moral hazard, a form of

negative social externality. For example, knowing that immunization against tetanus protects them

and their newborns from tetanus infection during child birth, the mothers might choose to deliver

at home rather than at health facilities. Such a choice could expose the newborn to death risks

associated with poor general care during delivery, despite being at good health in the uterus.

The demand for tetanus immunization is estimated simultaneously with a model of birth weight

determination. In the birth weight model, tetanus immunization is assumed to improve child health,

which is consistent with the complementarity hypothesis.

3.1.2 Estimation Issues

Equation (2) is the basic model for estimation of the effect of tetanus immunization on birth

weight when Z is interpreted as tetanus vaccination, and H as birth weight. In equation (2), tetanus

immunization is endogenous to birth weight because it is a choice variable. Hence, instruments for

tetanus immunization are needed in order to consistently estimate the effect of immunization on

birth weight (Bound et al, 1995). The instruments for mother’s tetanus immunization are factors

that affect the demand for tetanus vaccination without influencing directly the birth weight. From

the UDHS 2006, the identified instruments for mother’s tetanus immunization include household

residence (urban or rural), household access to mass media, household ownership of agricultural

land (as a proxy for wealth), mother’s employment status, and time taken by mother to collect

water.

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Estimation of equation (2) has potential sample selection bias because some of the children in the

1996 survey did not have birth weight. In particular, children born at home did not have birth

weights. The Heckman model is used to correct for sample selection bias (Ajakaiye and Mwabu,

2007; Wooldridge, 2002; Heckman, 1979). The Heckman model involves the specification of the

equation of interest and the selection equation. The selection equation is a probit model for

selection of the unit of study into the estimation sample without directly affecting birth weight. In

this study the unit of analysis is the child. A child is included into the estimation sample only if he

or she had a birth weight extracted from a growth-monitoring card. The factors that identify the

sample selection equation are the same as those that identify the demand for tetanus immunization.

In addition, the heterogeneity of birth weight due to non-linear interaction of tetanus vaccination

with unobservables and omitted variables could bias the estimated structural coefficients. The

control function approach is used to address the issue (Ajakaiye and Mwabu, 2007; Garen, 1984;

Wooldridge, 1997).

Following Ajakaiye and Mwabu (2007) and Wooldridge (2002), the estimation equations can be

summarized as follows:

B = w1δb + βM + ε1 ……………………………………………. (7.1)

M = wδm + ε2 …………………………………………………… (7.2)

G = 1(wδg + ε3 >0) ……………………………………………… (7.3)

where:

B, M, G are birth weight, immunization status of the mother, and an indicator function for the

selection of the observation into the sample respectively;

w1

w = exogenous variables, consisting of w

= a vector of exogenous covariates (mother’s age, mother’s education level, father’s education

level);

1 covariates that belong in the birth weight equation and a

vector of instrumental variables, w2, that affect immunization status (M) but have no direct

influence on birth weight (B). The instrumental variables (w2) include household residence (urban

or rural), household access to mass media, wealth index (as a proxy for household income),

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mother’s employment status, and time taken by mother to collect water;

δ, β, ε = vectors of parameters to be estimated, and a disturbance term, respectively.

The instrumental variable (2SLS) model based on equations 7.1 – 7.3 was estimated for the

determinants of birth weight. The variable definitions for the various equations are given in table 2

below.

Table 2: Definitions of Variables for the Study

Variable Definition

birthweight Weight of the child at birth, measured in kilograms birthreport Availability of the birth report (=1 if child born at a health facility,

otherwise zero) immunization status

Mother’s immunization status against tetanus (=1 if immunized, otherwise zero)

education level Mother’s educational level, measured in completed years of schooling age Mother’s age, measured in completed years birth interval Birth interval between the last pregnancy, measured in months antenatal visits Number of antenatal visits for last pregnancy smoking Mother’s smoking status (=1 if mother smokes cigarettes/tobacco,

otherwise zero) malaria Malaria infection dummy (=1 if mother infected with malaria during last

pregnancy, otherwise zero) wealth index Wealth index of the household, in quintiles (1=lowest, 2=second,

3=middle, 4=fourth, 5=highest). Used as a proxy for income urban Urban location of household (=1 if urban, otherwise zero) radio Dummy for access to radio (=1 if listened to radio at least once a week) newspapers Dummy for access to newspaper (=1 if read newspaper at least once a

week) television Dummy for access to television (=1 if listened to television at least once

a week) land Amount of agricultural land owned by the household, measured in acres.

This is used as a proxy for wealth employment status

Mother’s employment status (=1 if in paid employment in either the public or private sector, otherwise zero)

water Time taken by mother to collect water cooking and drinking. It is used as a proxy for the opportunity cost of time for immunization

Central Dummy for central region (=1 if central region) Eastern Dummy for eastern region (=1 if eastern region) Western Dummy for western region (=1 if western region) Northern Dummy for northern region (=1 if northern region)

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3.2 Qualitative Methods

3.2.1 The Qualitative Research Method

The qualitative data was generated using focus group discussions. Two focus groups were

selected from Kampala (representing the urban area) and Hoima (representing the rural area)

Homogeneity was achieved by recruiting groups which comprised seven mothers each who were

selected on the basis of their experience in child bearing and participation in antenatal services.

The mothers were selected in consultation with the local leaders who helped to identify suitable

participants for the discussions.

3.2.2 Qualitative Data Collection

For purposes of ethical considerations, participants were assured of confidentiality and their

consent was sought before the commencement of the discussions. As a result the names of the

participants have not been included in the report. The focus group discussions were conducted in

languages that participants are fluent Luganda for Kampala and Runyoro for Hoima). Discussions

were taped with the consent of the discussants.

The discussions were conducted using one topic guide which was formulated within the objectives

of the study and designed to capture different aspects of information regarding tetanus

immunization and poverty reduction. The purpose of the focus group discussions was to collect

data from several mothers at the same time and to provide them with relaxed enjoyable discussions

which are stimulated by arguments in order to generate shared views, feelings, experiences and

perceptions regarding the role of tetanus immunization to health status of the children/mothers,

household welfare and its subsequent contribution to poverty reduction. The discussions further

aimed at capturing information to supplement the findings of the quantitative analysis.

3.2.3 Qualitative Data Analysis

The qualitative data was captured using two techniques namely; tape recording and hand writing

by research assistants. The taped data were transcribed and edited together with written notes in

order to eliminate errors as soon as the interviews were done. Data were analysed using the

interpretive analysis. Data reduction was done by reading the data, identifying concepts and

breaking down the data in small parts/categories of concepts. The connections between the

categories of concepts were identified. Similar concepts were grouped together to form lager

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themes. More complex themes were identified in the existing themes while memos (important

thoughts) which were used to document issues were recorded. Interpretation was done by

drawing conclusions around patterns and trends. Some of the responses have been quoted

verbatim for purposes of illustration of thoughts.

4. Findings of the Study

The findings of the study are in two separate sections: quantitative method findings and the

qualitative method findings.

4.1 Quantitative Method Findings

4.1.1 Descriptive Statistics Weight at birth is an important reproductive health outcome which is indicative of the child’s

vulnerability to the risk of childhood illnesses and the chances of survival (UBOS, 2007). Weight

at birth is greatly influenced by the mother’s immunization status against tetanus and antenatal

care during pregnancy, including socio-economic factors. The demand for immunization and

antenatal care is also influenced by the mother’s socio-economic characteristics. According to

UBOS (2007), the likelihood of mothers having their last birth protected against neonatal tetanus

is influenced by education level, rural/urban residence, and regional location (see table 3).

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Table 3: Mother's Tetanus Immunization Status and Antenatal Care for last birth

Mother's Characteristics

Percentage Immunized against Neonatal Tetanus

Percentage Receiving Antenatal Care from a skilled provider

Number of Mothers

Mother's Age <20 73.6 95.4 777 20 - 24 76.4 93.7 3,427 35 - 49 74.6 92.0 831

Residence Urban 77.7 97.2 668 Rural 75.3 93.0 4,367

Region Central 1 62.8 89.7 497 Central 2 75.5 93.1 428 Kampala 75.4 96.7 298 East Central 77.0 92.7 510 Eastern 77.8 95.1 755 North 79.1 93.6 872 West Nile 83.7 98.7 289 Western 74.7 93.8 772 Southwest 74.8 91.4 615

Education No education 73.7 90.1 1,087 Primary 74.4 94.0 3,156 Secondary + 83.4 96.4 792

Wealth Quintile Lowest 77.0 93.2 1,074 Second 73.7 92.3 1,088 Middle 75.3 92.9 985 Fourth 75.5 93.2 961 Highest 76.9 96.4 928

Total 75.6 93.5 5,035 Source: UBOS (2007) Table 10.1 p. 118 and Table 10.5 p.122

Urban women (77.7 percent) were more likely to have their last pregnancy protected against

neonatal tetanus as compared to rural women (75.3 percent). Women with a higher level of

education were more likely to have their last pregnancy protected against neonatal tetanus (83.4

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percent for those with secondary and higher education as compared to 73.7 percent for those with

no education). By implication education level makes the mothers to be more informed of the

benefits of immunization. The mothers in the various wealth quintiles were almost equally likely to

have their last pregnancy protected against neonatal tetanus, which may be explained by the

government policy of free provision of immunization services. On a regional level, West Nile had

the highest neonatal immunization rates (83.7 percent).

Mothers who were more likely to seek for antenatal care from skilled providers (public and private

health facilities) were those resident in urban areas (97.2 percent), those with higher level of

education (96.4 percent), and those from the highest wealth quintile (96.4 percent). Again the

mothers from West Nile region were more likely to seek for antenatal care from skilled providers

(98.7 percent). It should be noted that the primary objective of antenatal care is to identify and

treat problems during pregnancy (such as anaemia and infections), screen for complications and

advice on a range of issues that promote the well-being of the unborn baby and the mother. The

minimum antenatal health care package for Uganda includes provision of iron tablets or syrup,

treatment for intestinal parasites, weight measurement, checking blood pressure, testing of blood

and urine samples. Table 4 presents the status of antenatal care visits by rural/urban residence.

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Table 4: Number of Antenatal Care Visits (ANC) and Timing of First Visit

Number and timing of ANC visits Urban Rural Total None 1.8 4.9 4.5 One 5.1 5.7 5.6 Two to three 30.9 43.3 41.7 Four or more 59.6 45.3 47.2 Don’t know 2.5 0.8 1.0 Total 100.0 100.0 100.0

Number of months pregnant at time of first ANC visit

Urban Rural Total

No antenatal care 1.8 4.9 4.5 Less than 4 18.7 16.3 16.6 Four to five 39.9 41.5 41.3 Six to seven 35.2 32.9 33.2 Eight or more 4.3 4.2 4.2 Total 100.0 100.0 100.0

Number of women 668 4367 5035 Source: UBOS (2007) Table 10.2 page 119

Of the 5,035 women, the majority (47.2 percent) had four or more antenatal care visits, while 41.7

percent had between two to three antenatal care visits. However the urban women were more

likely to have four or more antenatal care visits (59.6 percent) as compared to rural women (45.3

percent). The majority of the women (41.3 percent) were more likely to go for the first antenatal

care visit when the pregnancy was between four to five months. There is a need for concerted

efforts to improve early antenatal care attendance so as to provide early opportunities to diagnose

problems, provide treatment, and prevent further complications. UBOS (2007) also notes that

provision of the minimum antenatal health care package in Uganda is largely inadequate.

The major constraints reported by mothers in accessing health care include lack of money to pay

for treatment (65 percent), distance to the health facility (55 percent), lack of transport (49

percent) and unavailability of medications (46 percent) [UBOS, 2007].

As earlier pointed out, the mothers’ tetanus immunization status and antenatal care attendance

have significant implications on the child’s birth weight, which is a reproductive health outcome.

Children with a birth weight of less than 2.5 kgs are considered as low birth weight (LBW) and

have a higher than average risk of early childhood death (Kutty, 2004). Table 5 presents the

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distribution of child birth weights in Uganda by mothers’ characteristics.

Table 5: Distribution of Child Birth Weights by Mother’s Characteristics Mother's Characteristics

Less than 2.5 kgs

2.5 kgs or more

Total No. of births

(Percent) (Percent) (Percent)

Mother's age <20 12.9 87.1 100.0 593 20 - 34 9.9 90.1 100.0 2,024 35 - 49 13.6 86.4 100.0 327

Mother's smoking status

Smokes ciggaretes/tobbaco

15.0 85.0 100.0 72

Does not smoke 10.8 89.2 100.0 2,872

Residence Urban 9.0 91.0 100.0 694 Rural 11.5 88.5 100.0 2,251

Region Central 1 14.8 85.2 100.0 331 Central 2 12.0 88.0 100.0 287 Kampala 8.5 91.5 100.0 327 East Central 10.5 89.5 100.0 330 Eastern 9.5 90.5 100.0 485 North 12.5 87.5 100.0 495 West Nile 7.5 92.5 100.0 158 Western 11.3 88.7 100.0 338 Southwest 8.8 91.2 100.0 192

Education No education 12.6 87.4 100.0 425 Primary 11.0 89.0 100.0 1,762 Secondary + 9.7 90.3 100.0 758

Wealth Quintile Lowest 12.7 87.3 100.0 521 Second 9.9 90.1 100.0 471 Middle 9.1 90.9 100.0 439 Fourth 13.0 87.0 100.0 610 Highest 9.9 90.1 100.0 904

Total 10.9 89.1 100.0 2,945 Source: UBOS (2007), Table 11.1 page 136

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Of the 2,945 births with a reported birth weight, 10.9 percent were below the recommended 2.5

kg weight. Birth weight is lower among children born to older women (age at birth 35 – 49),

children born to smoking mothers, and children of women with no education. Birth weight also

varies by the mothers place of residence. Rural women have 11.5 percent of births with a birth

weight of less than 2.5 kgs as compared to 9.0 percent of urban women. Central region has the

highest proportion of low birth weight as compared to other regions (UBOS, 2007).

4.1.2. Instrumental Variable (2SLS) Estimation Results for Determinants of Birth Weight

The regression results are presented in table 6. For the first-stage regression, the dependent

variable was the probability of a mother receiving at least one tetanus injection during the last

pregnancy (= 1 if immunized against tetanus, otherwise zero). For the instrumental variable

(2SLS) regression, the dependent variable was the birth weight (in kgs).

Table 6: Instrumental Variable (2SLS) Model for Determinants of Birth Weight

First-stage Regression Dependent Variable: Mother's Immunization Status (=1 if immunized against tetanus) Explanatory Variables Coefficient t Prob>t Mother's age, in years 0.0059 4.01 0.0000 Mother's education, in years 0.0032 2.87 0.0084 Number of antenatal visits 0.0296 5.99 0.0000 Malaria infection dummy 0.0391 1.79 0.0730 Mother's smoking status (=1 if smokes cigarates) 0.0737 1.66 0.0970 Wealth Index, in quintiles 0.0250 2.68 0.0070 Urban dummy (=1 if urban) 0.0669 1.89 0.0590 Time spent fetching water, in hours -0.0027 0.57 0.5670 Frequency of listening to radio 0.0043 2.46 0.0090 Frequency of reading newspapers 0.0432 2.51 0.0120 Frequency of listening to television 0.0096 0.56 0.5730 Constant 0.8475 15.82 0.0000

No. of observations 1,726 F(11, 1714) 8.25 Prob>F 0.0000 R-squared 0.0503 Adjusted R-squared 0.0442 Root MSE 0.4144

Instrumental Variables (2SLS) Regression Dependent Variable: Birth Weight (in kgs) Explanatory Variables Coefficient t Prob>t Mother's immunization status 0.0356 3.51 0.001 Mother's age, in years 0.0039 1.37 0.1710 Mother's education, in years 0.0079 1.71 0.0870 Number of antenatal visits 0.0139 2.12 0.0260

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Malaria infection dummy -0.0794 2.29 0.0220 Mother's smoking (=1 if smokes cigarates) -0.1520 2.10 0.0360 Constant 3.3413 12.09 0.0000

No. of observations 1,726 F(11, 1714) 3.82 Prob>F 0.0009 R-squared 0.2139 Adjusted R-squared 0.2075

(i) First Stage Regression Results: Determinants of Mother’s Immunization Status

The first-stage regression results give the determinants of the probability for mother’s tetanus

immunization. The estimated parameters of the model are jointly statistically different from zero as

indicated by the Prob>F = 0.0000. The t-value measures the significance of the parameter

estimate, holding other factors constant. In general any t-value which is equal to or greater than

two implies that the estimated parameter is statistically different from zero. The actual measure of

the probability that the parameter estimate is equal to zero is given by prob>t, where prob>t being

less than or equal to 0.1 denotes that the parameter estimate is statistically different from zero at

least at the 10 percent significance level.

Age has a positive and significant effect (at the 1 percent significance level) on the probability of a

mother being immunized against tetanus. This is consistent with the expectation because older

mothers are more likely to have received tetanus immunization for the last pregnancy or previous

pregnancies. According to UBOS (2007), tetanus immunization is given to pregnant mothers to

prevent neonatal tetanus. If a woman has received no previous tetanus toxoid (TT) injections, for

full protection, a pregnant mother needs two doses of TT during pregnancy. However if a woman

was immunized before she became pregnant, she may require one or no TT injections during

pregnancy. For a woman to have lifetime protection, a total of five doses is required. Hence older

women have a higher likelihood of receiving tetanus immunization.

Mother’s education level as measured in completed years of schooling has a positive and

significant effect (at the 1 percent significance level) on the probability of a mother being

immunized against tetanus. The intuition of this result is that education increases the level of

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awareness of the dangers neonatal tetanus which includes death, hence raises the demand for

immunization. The policy implication of this result is that improving the levels of education of girls

is critical in enhancing the health status of future unborn children through increased demand for

tetanus immunization. The current universal primary and secondary education policy in Uganda

which focuses on the girl child is a step in the right direction. These findings are consistent with

Elo (1992) who observed a strong positive association between female education and the use of

maternal health-care services in Peru. Blunch (2004) also noted that in Ghana educated mothers

were more likely to seek pre-natal care for themselves and post-natal care for their children and

also experience lower child mortality as compared to mothers with no education.

The wealth index of the household (used as a proxy for household income) was constructed in

quintiles (1 = poorest, 2 = poorer, 3 = middle, 4 = richer, 5= richest). The results suggest that

income has a positive and significant effect (at the 1 percent significance level) on the demand for

tetanus immunization. By implication the women from the wealthier households were more likely

to have a higher demand for tetanus immunization as compared to women from poorer

households. Given the fact that government policy is to provide tetanus immunization free of

charge to all pregnant mothers, what these results suggest is that there are some costs associated

with immunization (such as distance to health facilities and transport costs) that may constrain the

demand by women from poorer households. This view is supported by UBOS (2007) which

observed that access to health care by women is constrained by distance to health facilities (55

percent) and lack of transport (49 percent). Ssengooba et al (2003) also argued that overall

maternal health status in Uganda is correlated with women’s access to household income.

Ssengooba et al (2003) further argued that women’s occupation and ability to earn money are

important for their ability to save for maternity care. This is explained by the fact that the sharing

of information between couples about their household incomes is generally poor , which negatively

affects women’s bargaining power when they needed to decide to seek maternal health services

with their partners. They further argued that the decision-making power of women for seeking

health services during pregnancy is limited by social and cultural factors (for example, in most

cases decisions are taken or dictated, by relatives and their husbands).

The time spent on collecting water was included in the model to capture the opportunity cost of

22

tetanus immunization. It was hypothesized that mothers who spend long hours fetching water (for

drinking and general home use) would have a higher opportunity cost and would more likely not

go for immunization. However the empirical results suggest that time spent on fetching water has

a negative but insignificant effect (at least at the 10 percent significance level) on the probability of

mother’s tetanus immunization.

Being located in urban areas has a positive and significant effect (at 1 percent significance level)

on the probability of mother’s tetanus immunization. This may be explained by the fact that urban

areas are better endowed with infrastructure which reduces the travel opportunity costs (both

financial and time) to health facilities. In addition, the health facility distribution tends to be higher

in urban areas as compared to rural areas. In addition to major public health facilities (such as

hospitals) which are located in urban areas, the private health facilities tend to be highly

concentrated in urban areas and they also provide free tetanus immunization services funded by

the government. This explains why access to tetanus immunization is higher in urban areas than

rural areas. These findings are consistent with Elo (1992) who observed that women who grew

up in rural towns were less likely to seek modern maternal health-care services during pregnancy

and delivery as compared to women who grew up in cities.

The variables for access to mass media (radio, newspapers, television) were constructed as

dummies (=1 if accessed at least once a week, otherwise zero). The results suggest that access to

radio and newspapers have positive and significant effects (at 1 percent and 5 percent significance

levels respectively) on the demand for immunization services. These results may be explained by

the wide coverage of radio services even in rural areas. In addition to the state radio, there are

now many private radio stations operating within the various regions of the country and broadcast

health education programmes in local languages. This contributes to an increase in knowledge on

the benefits of maternal and child immunization, which explains the positive and significant

coefficient for radio access. The state-owned newspaper (The New Vision) and the several

private newspapers in the country also have health education columns which educate the public on

the benefits of maternal and child immunization. This may explain why those with access to

newspapers are more likely to demand tetanus immunization. Television access, though having a

positive coefficient, was statistically insignificant. This may be explained by the fact that television

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access is not widely spread especially in rural areas.

In conclusion, the demand for tetanus immunization services is positively and significantly

influenced by age, education level, income, being urban based, and access to radio and

newspapers.

(ii) Instrumental (2SLS) Regression for Determinants of Birth Weight

Mother’s tetanus immunization status has a positive and significant effect (at 1 percent

significance level) on birth weight. This underscores the fact that tetanus immunization is an

important health input that impacts on the infant’s well-being through birth weight (Corman et al,

1987; Currie and Moretti, 2003; Rosenzweig and Schultz, 1983). Birth weight may also be viewed

as an input for the initial endowment of an infant’s “health human capital”

Mother’s age has a positive but insignificant effect (at 10 percent significance level) on birth

weight. These results are consistent with Mansour et al (2002), who in a study of 2000 mothers

in Egypt, observed that old maternal age (35+ years) is a significant risk factor for low birth

weight. However Makki (2002) observed that younger mothers (19 years or less) were more likely

to have low birth weight babies in Yemen.

Mother’s education has a positive and significant effect (at 10 percent significance level) on birth

weight. The intuition is that more educated mothers have better information that influences their

behaviour towards nutrition, tetanus immunization and antenatal care during pregnancy all of

which have positive effects on the child’s birth weight. These findings are consistent with the

Tennessee Department of Health (2007) findings that the incidence of low birth weight decreased

with increasing maternal education level, from 11.3 percent among women with less than a high

school education to 7.2 percent among those with a bachelor’s or higher level college degree. The

women with less than a high school education were 40 percent more likely to deliver a low birth

weight infant than women with higher levels of education (p<0.001).

Malaria infection during pregnancy has a negative and significant effect on birth weight (at 5 per

cent significance level). The malaria infection dummy variable was constructed as follows: (=1 if

24

mother had malaria infection during pregnancy, otherwise zero). The negative coefficient of the

malaria infection dummy is consistent with Guyatt and Snow (2004) who argued that malaria

infections have a substantial adverse effect on pregnancy outcomes (causing both premature birth

[gestation of <37weeks] and intrauterine growth retardation [IUGR], which lead to low birth

weight (LBW).

Antenatal visits have a positive and significant effect (at 5 percent significance level) on birth

weight. As pointed out in the descriptive statistics, the antenatal care visits are used to diagnose

and treat for any infections which affect the unborn babies. The results suggest that the higher the

number of antenatal visits, the higher the birth weight. These results agree with the findings by

Negi et al (2006) that mothers with one antenatal visits had almost six times higher risk of having

a LBW as compared to mothers who had 5 or more antenatal visits. Further evidence by Joshi et

al (2005) suggested that in India the proportion of LBW was higher (61.7 percent) in mothers

who did not receive any antenatal care, followed by those who received inadequate care (46.5

percent). There was significant association between birth weight and utilization of antenatal care

by mothers (p < 0.001).

The mother’s smoking of cigarettes /tobacco during pregnancy has a negative and significant

effect (at 5 percent significance level) on birth weight, which is consistent with empirical literature.

Vogazianos et al (2005) noted that smoking by pregnant mothers was a major cause of LBW in

Cyprus. There was evidence of significant weight decrements for babies born prematurely to

smoking mothers (mean decrements of 886 grams in the period 1990-1998 and 821 grams in the

period 1998-2002). Similar evidence was adduced by Deshmukh (1998) who noted that tobacco

exposure was a significant risk factor for LBW. Further empirical evidence by Almond et al

(2002) also suggested that maternal smoking during pregnancy has negative and significant effects

on birth weight and gestation length (thus lead to premature birth).

In summary, birth weight is positively and significantly influenced by mother’s immunization status

against tetanus, education level and antenatal care. However, birth weight is negatively and

significantly influenced by mother’s smoking of cigarettes/tobacco and malaria infection during

pregnancy.

25

4.2 Qualitative Study Findings

4.2.1 Utilization of Reproductive Health Services/ Tetanus Immunization

The findings of the study indicated that most of the women utilized antenatal services/care. The

services they received as part of the antenatal services included: tetanus immunization, family

planning services, testing for HIV/AIDS, folic acid tablets, vitamin tablets, general medical check

up, general education on health of the mother. The consensus of the respondents was that tetanus

immunization is important for protection against tetanus of both the child and mother during birth.

The majority of the mothers had received at least one tetanus immunization by the time of giving

birth. The birth weight of the babies as recorded by a majority of the discussants was normal;

ranging between 3.3 kg and 3.6 kg. However some few respondents who had not utilized antenatal

services and delivered at home did not have their babies weighed at birth. Evidence from those

mothers that had not utilized antenatal health care services for the last pregnancies suggests that

there is misconception that tetanus immunization causes still birth as stated by some respondents:

“…. we fear tetanus immunization because it causes still birth…”

The mothers who never utilized antenatal health care reported that they receive both advice and care from old mothers that did not receive antenatal services themselves. By implication this misconception is being passed from old mothers to new mothers. The additional reason for not utilizing antenatal care services was the poor handling by medical personnel. One respondent reported:

“…they press your stomach and leave you in much pain…”

What this points to is the need for improvement in the delivery antenatal services so as to

encourage their utilization. Apart from the professional training, it is important for medical

personnel to have attitudes of tender care for the mothers. In addition to that there is need to

invest in sensitization programmes so as to change the attitudes of those women who do not use

antenatal services.

5.2.2 Economic Activities

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The study confirmed that good health condition of the mothers and their babies creates time which

can be used for various economic activities. As reported by the discussants a majority of women

are engaged in small business such as selling agricultural produce (such as milled rice, beans,

vegetables) and general merchandise. The estimated monthly earnings from those small business is

about Uganda Shs120,000 which is not much. Concerning the earnings, the study established that a

majority of the participants make independent decisions regarding the use of earnings by

themselves. The earnings are used for daily needs such as food, clothing, soaps, school fees,

medical treatment and rent payments.

However, all discussants generally acknowledged that the income which they get is not sufficient

to meet household needs. They asserted that there is no improvement in their conditions of living

due to increasing cost of living. The participants expressed dissatisfaction with the income which

they have as shown in their responses below:

“…the money is too little... it is not improving our living conditions at all…”

However, discussants were of the view that although the income they receive from

their economic engagements is little, their living conditions would have been much

worse without it.

“…. the income is helpful although it does not change our quality of life very much ….

Our living condition would have been worse without this business income because though

it is small it helps us to feed the families, educate children, pay house rent … ”

On what Government should do to assist them to improve their living condition, the

discussants pointed to improved service delivery especially health services.

“….the government health facilities are poorly stocked with drugs so we spend most of

the earnings on medical treatment in private clinics….the cost of drugs is very high…”

27

The above expressions reveal that despite the earnings, high levels of poverty still persist due to

increasing costs of living. In addition inadequate provision of social services (especially inadequate

supply of drugs to government health facilities) to the poor is a contributory factor to their poverty

state because their meager earnings which would have been utilized on income

generating/developmental projects are spent on private health care.

4.2.3 Factors Which Hinder Proper Utilization of Time

Lack of capital

The findings of the study revealed that the available time which has been created by good health

conditions of the mothers and their babies is not being utilized effectively to generate adequate

income to address poverty. The participants asserted that they do not have enough capital to

enable them to carry out profitable businesses. As a result they use time on activities that hardly

generate income (e.g. subsistence agriculture) which nonetheless are important for the

improvement of their welfare. The respondents expressed dissatisfaction regarding accessibility to

credit as shown by the expressions below:

“…. the loan conditions are not good…. the interest rates are too high and we can not borrow money from banks….”

High Taxes

In addition to lack of capital, the respondents reported that they experience high levels

of taxation on their small businesses. There is a lot of disrupt ion of their businesses by

the city/town council tax authorities such that a significant amount of the earnings go

for tax. Some of the taxes such as market levy are paid on a daily basis and in the

event that one is not able to raise it due to poor sales the goods are confiscated by the

tax collectors.

Gender Division of Labour

The gender division of labour was also identified as a barrier to utilization of time for economic

activities. A majority of participants expressed that they cannot use all the time which they have on

28

economic activities because they have additional reproductive roles which are perceived by society

as women’s roles. Reproductive roles include child care, cooking, washing and caring for the sick.

The combination of domestic roles with business activities make them very tired as noted in their

response below:

“…. in diversifying sources of livelihood, one has to do digging in the garden first before

reporting to the small business activity …… and later do household work …”

In conclusion, the study confirmed that tetanus immunization enhances the normal birth weight of

the babies and promotes good health conditions of the mothers and babies. Consequently, the time

which would be spent in sickness is freed for utilization in economic activities. However, the

utilization of the additional labour supply in economic activities is constrained by lack of capital, lack

of access to bank credit, high taxes, and gender division of labour.

4.2.4 Policy Recommendations from Qualitative Study

Reduction of Taxes

The respondents argued that the high taxation of their small business is stifling their growth and

reduces their earnings. Their recommendation was that the taxes should be reduced.

Improvement in Supply of Drugs in Government Health Units

Currently the supply of drugs to government health units is very poor forcing the people to rely on

private health facilities where the cost of drugs is very high. As a result, a high proportion of the

income goes to the purchase of drugs. The recommendation from the respondents is that

government should improve the supply of drugs to the health units to improve the welfare of the

poor.

Improvement of Access to Credit and Loan Terms

Mechanisms should be designed to enable women access bank as well as government credit

schemes. The terms for the government credit scheme “Boona Bagagawale” (interpreted as

“Prosperity for All”) which was designed to improve the welfare of the poor should be improved by

29

reducing interest rates and longer repayment periods.

Improvement for Antenatal Services /Care

The participants expressed that whereas government has tried to sensitize and put in place antenatal

care facilities, improvement should be done in service delivery and more sensitization regarding

tetanus immunization. The mothers need more explanation on how tetanus immunization helps to

protect the unborn baby and the mother. In addition, antenatal care should strictly be provided by

qualified and experienced medical personnel.

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