CHAPTER ONE
BACKGROUND TO THE STUDY
1.0 INTRODUCTION
Expectant and nursing mothers, infants and children constitute the most vulnerable segments of a population from the nutritional standpoint. In any consideration of the problem of malnutrition,' these segments require special consideration, as this unfortunate nutritional situation is prevalent in many under-developed countries today. Pregnancy constitutes states of considerable physiological stress which impose increase nutritional demands (Gopalan, 2000).
Pregnancy deserves planning because many practices or conditions of the mother that harm the developing fetus are modifiable, such as the following: Alcohol consumption, Use of certain medications, such as heavy use of aspirin, Use of illegal drugs, such as cocaine or marijuana, Job-related hazards and stresses, Smoking, Inadequate diet, such as too little iron, zinc, and synthetic folic acid, Excess vitamin A intake and mega dose use of other nutrient supplements, Heavy caffeine use, Lack of medical treatment with HIV -positive status or AIDS, Poor control of ongoing diabetes or hypertension (ADA Reports, 2000).
Women need to pay attention to these risks in the months before conception. This precaution is necessary because women often do not suspect they are pregnant during the first few weeks after conception and may not seek medical attention until after the first 2 to 3 months.
Still, even without fanfare, the child-to-be grows and develops daily. For that reason, the health and nutrition habits of a woman who is trying to become pregnant - or has the potential to become, pregnant - are particularly important. Although some aspects of fetal and newborn health are beyond control, a woman's conscious decisions about Social, health, and nutritional factors affect her infant's health and future. Much research suggests that an adequate vitamin and mineral intake at least 8 weeks before conception and during pregnancy can help prevent birth defects such as neural lube defects. This problem has been Iinked-in part to a foliate deficiency.
In addition, about 50% of pregnancies are unplanned. For these reasons, parents should be aware of the role nutrition plays in the development of a healthy infant both before and during pregnancy. According to Scholl &Johnson, 2000), the stages of pregnancy include: Prenatal Growth, Development and the Early Growth. For B weeks after conception, a human embryo develops from an ovum into a fit for about another 32 weeks, the fetus continues to develop. When its body finally matures, the infant is born. Until birth, the mother nourishes it via a placenta, an organ that forms in her uterus. The placenta separates the blood supply of the mother from the blood supply of the fetus. Nutrients pass from the mother's blood through the placenta to accommodate the growth and development of the fetus.
In the formation of the human organism, egg and sperm first unite, producing the Zygote. From this point, the reproductive process occurs very rapidly: Within 30 hours-zygote divides in, half to form 2 cells, Within 4 days cell number climbs from 64 to128 cells. At 14 days-the group of cells is called an embryo, Within 35 days-heart is beating, embryo is / of an inch (8 millimeters) long eyes and limb buds are clearly visible, At 8 weeks-the embryo is known as a fetus, At 13 weeks (end of first trimester-most organs are formed, and the fetus can move.
For purposes of discussion, the duration of pregnancy-normally, 37 to 41 we from the mother's last menstrual period-is commonly divided into three periods called trimesters. Growth begins in the first trimester with a rapid increase in cell number.
The most serious damage to the fetus from exposure to toxins is likely to occur during the first 8 weeks after conception, two¬ thirds of the way through the first trimester. However, damage to vital parts of the body - including the eyes, brain, and genitals ¬can also occur during the last months of pregnancy.
This type of growth dominates embryonic and later fetal development. The newly formed cells then begin to grow larger. Further growth and development then involve mostly an increase in cell number with some increase in cell size. By the end of 13 weeks-the first trimester-most organs are formed and the fetus can move.
Nutritional deficiencies and other insults transmitted through the mother to the embryo or fetus-for example, injuries caused by medications and other drugs, high intakes of preformed vitamin A" radiation, or trauma-can alter or arrest the current phase of development. . The effects may last a lifetime. The most critical time for these problems to happen is during the first trimester. Most miscarriages (more correctly termed spontaneous abortions) occur at this time. Currently, about one-half or more of all pregnancies either fail to attach to the uterine wall or undergo spontaneous abortions, often so early that a woman does not even realize she was pregnant. The early spontaneous abortions usually result from a genetic defect or fetal error in fetal development. Stuart, et al., (2003).
A woman should avoid substances that may harm the developing fetus, especially during the first trimester. This holds true for the time when a woman is trying to become pregnant. As previously mentioned, she is unlikely to be aware of her pregnancy for at least a few weeks. In addition, the fetus develops so rapidly during the first trimester that if an essential nutrient is not available, the fetus may be affected even before evidence of the deficiency appears in the mother.