Good nutrition and healthy lifestyle are important to a better quality of life, but both can be crucial during pregnancy. Inspection of the research indicates that sound nutritional practices during pregnancy have always been considered important in the development of the unborn child Allen, 2005). However, good maternal nutrition may also be an important factor in the development of the fetus before the mother becomes pregnant and the effects of maternal nutrition on the fetus may extend well beyond childhood into adulthood (Barker, 1992).
Obviously the use of alcohol and certain drugs is not recommended during pregnancy. The consequences of alcohol and drug use during pregnancy have been well-documented and need not be discussed here (e.g., Streissguth, Barr, & Martin, 1984). With respect to pre-pregnancy plans, the National Institute of Health suggests three things that should be undertaken before a woman becomes pregnant: (1) both prospective parents should have physical examinations with their primary care physician; (2) potential mothers should lose excess weight before becoming pregnant; and (3) both parents should make appropriate healthy lifestyle changes such as quitting smoking, exercising, and improving diet prior to the mother becoming pregnant (http://nih.gov/). Establishing good dietary habits before pregnancy can lead to the maintenance of good nutritional intake during pregnancy and beyond.
Interestingly, good nutrition during pregnancy has generally been regarded as important in the development of the baby despite an early lack of empirical evidence on humans to support this notion. Nonetheless, early empirical research with animals demonstrated that a lack of adequate nutrition by the mother during gestation can have permanent effects on the offspring, especially if inadequate nutrition occurs at during sensitive periods of fetal development (e.g., Winick & Noble, 1966). The early animal research established that inadequate maternal nutrition resulted in offspring that were of lower weights at birth and offspring that were not as hardy as those born to well-nourished mothers. Later epidemiological studies in humans indicated that the most important determinants of restricted fetal growth in humans are: (1) cigarette smoking by the mother during pregnancy; (2) a low maternal pre-pregnancy Body Mass Index (BMI); and (3) a low gestational weight gain in the mother (Kramer, 1998). These last two factors most likely reflect inadequate food intake by the mother during pregnancy, especially inadequate intake of so-called macronutrients. Macronutrients come from sources of nutrition that comprise the bulk of a normal diet and include carbohydrates, proteins, fats, certain minerals, and water.
The consequences of restricted fetal growth and low birth weight in humans include increased infant mortality and numerous childhood health issues that were previously well-documented in the literature (e.g., McCormick, 1985). Epidemiologic studies linking size at birth to disease in adulthood have also demonstrated that placental weight and thinness at birth, indicated by ponderal index, is a valid marker of fetal growth in addition to weight for gestational age. For instance, Moore, Davies, Willson, Worsley, and Robinson (2004) using both the weight of the infant and the ponderal index found that the mother's diet was directly related to the size of the baby at birth in a large sample of Australian mothers. Such an inadequate intake of food may be related to poverty or to a cultural desirability to maintain a thin figure. The interest in nutrition during pregnancy has also been bolstered by the Fetal Origins of Adult Disease Theory (Baker, 1992). This theory proposes that low birth weight in infants is strongly associated with an increased susceptibility to cardiovascular disease, cancer, and Type II diabetes in adulthood as a consequence of physiologic adaptations of the fetus to poor nutrition in the womb (Godfrey & Barker, 2000).
Micronutrients consist of vitamins and trace minerals that are required in very small amounts. Of course a lack of micronutrients would also be present in most anyone not eating an adequate diet, but could also be an issue for pregnant women who maintain good term weight gains. Micronutrient inadequacies can affect the development of the fetus throughout pre-pregnancy to lactation, but it is difficult to determine how much of a specific nutrient is needed by women as there is a general lack of pregnancy-specific laboratory indexes for nutritional evaluation (Allen, 2005). However, several micronutrients are recognized as important. Iron deficiency in the mother has been linked to low birth weights and anemia (e.g., Picciano, 2003). Deficiencies in folic acid, riboflavin, vitamin B-6, or vitamin B-12 have been linked to adverse pregnancy outcomes such as abruptio placentae, spontaneous abortions, neural tube deficits, or low birth weights (Allen, 2005). Iodine deficiency has been long known to effect fetal status (McCormick, 1985). Recently, poor vitamin D intake, associated with poor fetal skeletal development has become a concern for pregnant women that do not eat dairy products or take supplements (Allen, 2005). Other micronutrients of concern could include adequate intake of zinc, vitamins A and C, calcium, and antioxidants. However it should be noted that there is some research that indicates that taking supplements, other than iron, may not significantly increase infant birth weights (Ramakrishnan, Gonzalez-Cossio, Neufeld, Rivera, & Martorell, 2003).
On the other side of the coin, gaining too much weight during pregnancy can result in the risk of obesity in the mother, complications with delivery, and a greater risk of obesity in the child. One study found that nearly 40% of pregnant women gain more than the recommended amount during their pregnancy (Rooney & Schauberger, 2002) and other studies indicate that less than 50% of women adhere to recommended weight gain guidelines and gain more or less than the recommended amounts (Picciano, 2003). Current recommendations for healthy American women at a normal weight for their height (BMI of 18.5 to 24.9) indicate a gain 25 to 35 pounds during pregnancy should be considered healthy. For women that would be considered underweight (BMI less than 18.5) there should be a higher weight gain, 28 to 40 pounds, whereas women with a higher BMI (25 to 29.9) should gain only between 15 to 25 pounds (Picciano, 2003). In general, women who start with a normal BMI should expect to gain an average of a pound a week during the second and third trimesters and much less during their first trimester. Individual weight gain can of course vary substantially depending on a number of factors including the mother's pre-pregnancy weight or her age, so expectant mothers should always keep in close contact with their physicians in order to determine the exact weight gain that is appropriate for them.
A healthy diet during pregnancy is one that should include all the basic food groups including plenty of fruits, vegetables, whole grains, dairy products, and protein, while keeping the intake of saturated fats, trans fats, cholesterol, added sugars, and salt to a minimum. Additional caloric intake need only be an extra 300 calories a day for most women (Picciano, 2003). If a balanced diet is eaten and this rule of thumb is followed most pregnant women will easily satisfy their macronutrient needs (Institute of Medicine, 1990). Micronutrient needs are often met with a combination of diet and vitamin supplements.
According to the Institute of Medicine and other researchers (e.g., Allen, 2005; Picanno, 2003) nutrients that may be important to add by way of supplementation include:
(1.) Iron. Foods rich in iron include meats (especially red meat and liver), fish, poultry, leafy green vegetables, and eggs. There is iron in some enriched grains, but this may not be easily absorbed. Iron supplements can also be taken under a physician's supervision.
(2.) Folic acid. Supplementation with folic acid should start before the woman becomes pregnant and guidelines suggest that an additional 400 micrograms (mcg) of folic acid per day should be taken by most pregnant women (Rosenquist & Finnell, 2001). Foods high in folic acid include liver, lean meat, dark green leafy vegetables, oranges, grains and legumes.
(3). Calcium. Many most women do not get sufficient calcium in their diet prior to being pregnant (Picciano, 2003). Institute of Medicine (1990) recommends between 1000 and 1300 milligrams of calcium per day depending on age. Calcium should be taken under a physician's supervision as 2,000 mg/day or more of calcium can produce adverse health effects and certain supplements may not be absorbed easily into the body. Calcium-rich foods include dairy products, leafy green vegetables, and salmon. Vitamin D helps the body absorb calcium and the Institute of Medicine recommends 600 international units (IUs) per day depending on age, diet, and health issues.
There are also certain foods a pregnant woman should avoid. Undercooked meat can lead to toxoplasmosis which can lead to miscarriages or CNS disorders in the baby. Certain varieties of fish, (shark, swordfish, king mackerel, and tilefish) should be avoided during pregnancy due to potentially high levels of methyl mercury. In addition, pregnant and nursing women should not eat more than six ounces of albacore tuna or tuna steak per week and should limit fish consumption to two servings or 12 ounces per week.
For pregnant women or women considering becoming pregnant it is…