1.1 Background to the study
Nutrition is a major intrauterine environmental factor that alters expression of the foetal genome and may have life long consequences (Guoyao, Fuller, Timothy, Cynthia & Thomas, 2005). Alterations in foetal nutritional status may result in developmental adaptations that permanently change the structure, physiology and metabolism of the offspring, thereby predisposing individuals to metabolic, endocrine, and cardiovascular diseases in adult life (Guoyao et al., 2005). Maternal nutrition comprises of anthropometric factors such as pre-pregnancy weight for height (body mass index (BMI) and gestational weight gain which partly reflects the balance between energy intake and energy expenditure, but also includes increases in body water, as well as intake of protein and micronutrients (Tannys, Pat, Francesca & Leah, 2006). Of the pregnancy outcomes that might be affected by maternal nutrition, the one encountered most often in research literature is low birth weight. Other outcomes are deformities, morbidity and mortality rate (Kramer, 1998).
Low birthweight is defined as a body weight at birth of less than 2500g . There are two main causes of low birth weight: prematurity and intrauterine growth retardation (IUGR). Infants born with low birth weight suffer from extremely high rates of morbidity and mortality from infectious disease, and are underweight, stunted and wasted beginning in the neonatal period through childhood (ACC/SCN, 2000). The causes and effects of low birth weight are complex and best considered withins the lifecycle conceptual framework. Poor nutrition often begins in the intrauterine environment and extends throughout the lifecycle. Low birthweight is an intergenerational problem where low birthweight infants grow up to be undernourished and stunted children and adolescents and, ultimately undernourished women of child bearing age, and undernourished pregnant women who deliver low birthweight infants. This amplifies risk to the individual’s and perpetuates the cycle of poverty, undernutrition and disease. This is especially so when adolescents become pregnant before their own growth is completed, leaving little to fulfil their own or their infant’s nutritional requirement (ACC/SCN, 2000).
Any successful pregnancy requires the net deposition of tissue within the mother, the placenta and the foetus. Thus, there is a fundamental relationship between the nutritional status of the mother and her ability to transfer nutrients to the foetus at the appropriate time during pregnancy. The mother’s ability to achieve effective and timely transfer may however be constrained by factors other than her immediate dietary intake or overall nutritional status. The mother may have her own demands for nutrients that compete with the needs of the foetus. In a younger woman, the needs to complete her own growth and development have to be satisfied (Alan, Zulfiqar & Pisake, 2003).
Sub-optimal foetal growth is associated with higher foetal mortality, neonatal morbidity and mortality. Small size at birth is associated with greater susceptibility to infection and both altered postnatal growth and neuro cognitive development (Alan et al., 2003). Nutrition, acting either directly, or through specific endocrine mechanism is a major determinant of the pace and balance of foetal growth, with effects that have adverse consequence later in infancy and childhood. Modest changes in maternal diet, from very early in pregnancy, or even in the preconception period, can have marked effect on the ability of the foetus and newborn to withstand other infective or physical environmental stresses (Alan et al., 2003).
High rates of pregnancy-related mortality and morbidity persist in the poorer countries of the world (including Nigeria) with maternal mortality rates reaching over 1000 per 100,000 live births in some countries, and millions of infants are born too early, too small or with serious infections (ACC/SCN, 1993). Poor maternal nutritional status leads to many other complications for the mother and baby in both the short and long term. From nutritional status stems maternal weight gain, which strongly influences birth weight (Tannys et al., 2006).
Maternal under nutrition during gestation reduces placental and foetal growth of both domestic animals and humans. Available evidence suggests that foetal growth is most vulnerable to maternal dietary deficiencies of nutrients (such as protein and micronutrients) during the peri-implantation period and the period of rapid placental development (Wu et al., 2005). Under nutrition in pregnant women may result from low intake of dietary nutrients owing to either a limited supply of food or severe nausea and vomiting as hyperemesis gravidarum. This life threatening disorder occurs in 1-2% of pregnancies and generally extends beyond the 16th week of gestation. Pregnant women may also be at increased risk of under nutrition because of early or closely spaced pregnancies (Vause, Martz, Richard, & Gramlich, 2006).
When the mother has little control over family fund, dietary arrangement may become difficult. A woman’s access to and control over income and assets would be a major determinant of her nutrient intake (Mulokozi, 1999). Women’s occupation is such that they control fewer productive assets at every socio-economic level. In spite of the fact that they are responsible for meeting the family needs, they earn less income. This makes them resort to labour intensive jobs which add to their nutritional risk particularly for the pregnant women. Heavy workload for women might lead to poorer diets not only for their children and other members of the family but also for the women themselves (Mulokozi, 1991). The risk of improper nutrient intake and nutritional inadequacy during the periods of heavy physical work is high (Mozie, 2000).
Nutritional imbalance could cause detrimental effects to the pregnant woman, influence pregnancy outcome, and impair breast milk composition (Kontic-Vucinic, Sulovic & Radunovic, 2006). It is a well-known fact that foetal growth and development is strongly linked with maternal supply of essential nutrients e.g. vitamins. It is estimated that up to 30% of pregnant women suffer from a nutrient deficiency (Kontic-Vucinic et al., 2006). Without supplementation, about 75% would show a deficit of at least one nutrient (especially vitamins). Moreover, multi-nutrient deficit combinations often co-exist, and sub clinical depletions are probably common; consequences could be severe (Barasi, 1997; Kontic-Vicinic et al., 2006).
Maternal dietary imbalances at critical periods of development in utero can trigger an adaptive redistribution of foetal resources, including growth retardation. Such adaptations affect foetal structure and metabolism in way that predispose the individual to later cardiovascular and endocrine diseases. The correlation between low birth weight and later cardiovascular diseases and diabetes may arise from the fact that nutritional deprivation in utero programmes a newborn for a life of scarcity. Problems arise when the child’s system is later confronted by a world of plenty (ACC/SCN, 2000). Recent studies have shown a link with immune system development and subsequent risk of infection related mortality in adulthood. Analyses of over a thousand deaths in one community has shown that infants born in the wet season were ten times more likely than infants born in the dry season to die prematurely in adulthood, mainly from infection. The difference was manifested only after adolescence. This phenomenon may be due to abnormal growth of the thymus gland (immune cell producer) or the lymph system (immune cell transporter) during pregnancy (Barasi, 1997).
From the information enumerated above the importance of the nutritional status of women/mothers cannot be overemphasized. The consequences of inadequate nutrition and its impact on the unborn child are grave hence priority should be given to research in this area.
1.2 Statement of the Problem
Across the world, there is a high prevalence of adverse outcomes of pregnancy, which can be life threatening for both the mother and her baby. One of such outcomes is low birth weight (LBW). LBW is a major determinant of mortality, morbidity and disability in neonates, infants and children and also has a long-term impact on health outcomes in adult life. It accounts for up to 70% of neonatal deaths in some countries (Ross & Naeye 1999). Poor maternal nutrition and the resulting low birth weight (LBW) infants remain the single most important cause of infant morbidity and mortality in the world. Babies whose birth weight is low because of undernourishment face a greatly increased risk of death during the first months and years of life (ACC/SCN, 2000). The evidence also suggests that those children who do survive may be more likely to experience health problems throughout their lives; these include impaired cognitive development, as well as diabetes and coronary disease in adulthood (Bhargava, Sachdev, Fall, Osmond, Lakshmy & Baker, 2004).
In majority of LBW infants, the seed of death is sown much earlier before they are born. According to UNICEF (2012) infant mortality rate in Nigeria in 1990 was 126 per 1000 live births while in 2010 it was 88 per 1000 live births. Neonatal mortality was also estimated at 40 per 1000 live births. Current data from the Nigeria Demographic health Survey (NPC & ICF Macro, 2009) shows infant mortality to be 75 per 1000 live births, indicating a 25% drop from the value of 99 deaths /1000 live births recorded in 2003; while neonatal death remains at 40 per 1000 live births. Although these values are decreasing, they are still higher than the African average of 71/1000 live births of 2010 and almost equal to the Sub-Saharan average of 76/1000 in the same year in 2010 for infant mortality (UNICEF, 2012). Maternal mortality stands at 545 deaths/100,000 live births (NPC & ICF Macro, 2009).
There is significant variation in the incidence of low birth weight across regions. According to UNICEF (2012) data, values range from 6-27%, with South Asia having the highest incidence, while East Asia/Pacific has the lowest. India is home to nearly 40 per cent of all low-birth weight babies in the developing world. In Sub-Saharan Africa (including Nigeria) 13 per cent and in the Middle East/North Africa 11 per cent of infants are born with low weight. In Nigeria the prevalence of low birth weight is estimated at 12% (UNICEF, 2012). Report from Ebonyi State Ministry of Health indicates that pregnancy outcome in terms of maternal mortality and neonatal birth weight is not quite different from what is obtainable in other developing countries (Igboji, 2005). Based on hospital records collected from 1997-2000, a prevalence of low birth weight of 49.9% was recorded in Ebonyi State (Mozie, 2000). There is however a dearth of information on low birth weight rate presently in Ebonyi State.
Low birth weight in developing countries occurs primarily because of poor maternal health and nutrition. In addition, diseases such as diarrhea, malaria and respiratory infection, which are common in many developing countries, can significantly impair foetal growth when women become infected during pregnancy (ACC/SCN, 2000). More than 96 per cent of low birth weight occurs in the developing world, reflecting the higher likelihood of these babies being born in poor socio-economic conditions, where women are more susceptible to poor diet and infection and more likely to undertake physically demanding work during pregnancy (UNICEF & WHO, 2004). It reflects, further, a generational cycle of under nutrition, the consequences of which are passed along to children by mothers who are themselves in poor health or undernourished.
In a study conducted by Mozie (2000), she observed that women in Ebonyi State tend to work very hard; that theoretically, their husbands are looked upon as the bread-winners of the family but in practice the women are. This makes the women to work as hired labourers in quarries and in farms. They do domestic work, work in their own farms, do petty-trading and other strenuous jobs in order to feed the family and survive. Their level of physical exertion, lack of opportunity to rest and exposure to dangerous chemicals may be a contributing factor to low nutritional status and adverse pregnancy outcome.
Poor nutrition knowledge leads to superstition and misconceptions about food requirements and nutritive value of food, a very common condition in developing countries of the world (Mozie, 2000). Due to their level of poverty, poor educational background, and nature of their work, Mozie (2000) observed that Ebonyi women fed more or less on foods such as dried bread, roasted or boiled yam with little or no oil, occasionally and foo-foo with watery type soup devoid of vegetable in the midst of work. In other words, their feeding is predominantly starchy foods. This is also a major determinant of nutritional status, and pregnancy outcome.
Teenage pregnancy has been observed in some studies in Nigeria. Ene-Obong, Enugu & Uwaegbute (2001) found the mean age (in years) at marriage for less educated women (farmers and traders) to be 16.5 ±4.0 and 17.1± 4.0, respectively. Since pregnant teenage mothers are themselves growing, they compete with their own foetuses for nutrients. Low birth weights and pre-term delivery in adolescent pregnancies is almost three times higher than for adult pregnancies (Kontic-Vucinic et al., 2006). Bases on hospital records collected from 1997-2000, a prevalence of low birth weight of 50% was found among mothers of reproductive age and 75% for mothers below 20 years of age (Mozie, 2000). No wonder the government of Ebonyi State mounted various Mother and Child health programme in order to solve some of the problems enumerated. This study is therefore an attempt at determining the prevalence of low birth weight and identifying the factors that determine the birth weight of neonates.
1.3 Objectives of the study
The general objective of the study was to determine the effect of maternal nutrition knowledge and nutritional status on pregnancy outcome in rural and urban areas of Ebonyi state. The specific objectives included to:
(1) describe the general characteristics of pregnant women in rural and urban areas of Ebonyi State;
(2) assess the nutrition knowledge of pregnant women in rural and urban areas of Ebonyi State;
(3) assess the dietary habits of pregnant women in rural and urban areas of Ebonyi State;
(4) assess mothers’ perception of the effect of poor nutrition on pregnancy outcome in rural and urban areas of Ebonyi State;
(5) determine the mortality rate of neonates in rural and urban areas of Ebonyi State;
(6) determine the nutritional status of pregnant women in urban and rural areas in Ebonyi State using their hemoglobin status, nutrient intake and weight gain during pregnancy;
(7) determine the birth weight and anthropometric indices of neonates; and
(8) determine the effects of mothers’ nutrition knowledge, nutritional status and nutrient intake on pregnancy outcome in Ebonyi State.