Although an optimal eating pattern before and during pregnancy cannot guarantee a successful outcome of pregnancy, it can improve the chance of a healthy newborn baby, a healthy mom, and a healthy future for both. A woman who is well nourished and within her healthy weight range prior to conception provides an environment conducive to normal fetal growth and development during the critical first trimester of pregnancy. During pregnancy, the fetus cannot meet its genetic potential for development if the supply of energy and nutrients is inadequate. Conversely, excessive weight gain during pregnancy is strongly associated with maternal and fetal complications. An optimal eating pattern provides enough, but not too many, calories and nutrients to optimize maternal and fetal health.
This chapter discusses dietary guidelines for women before, during, and after pregnancy. Weight gain recommendations, common problems of pregnancy, and nutrition interventions for maternal health conditions are presented.
A mother’s health and nutritional status at conception, and even before, can affect the infant’s health, growth, and development over a life time. For instance,
A low folate status prior to conception increases the risk of neural tube defects.
An underweight mother has a higher risk of delivering a low birth weight (LBW) and small for gestational age (SGA) infant. Women who were LBW infants have a greater risk of having an LBW infant. LBW impairs infant growth and development.
Prepregnancy overweight/obesity increases the risk of large for gestational age (LGA), high body weight, macrosomia, and childhood overweight and obesity (Yu et al., 2013
A preconception eating pattern containing fish, meat, chicken, fruit, and whole grains is associated with reduced risk for preterm delivery, whereas an eating pattern high in fat, refined grains, and added sugar is associated with preterm delivery and shorter birth length (Grieger, Grzeskowiak, & Clifton, 2014
Low Birth Weight (LBW) a baby weighing less than 2500 g or 5.5 pounds.
Ideally, when women enter pregnancy they are optimally nourished, at a healthy body weight, exercise regularly, and do not smoke, drink alcohol, or use street drugs. However, even among women planning to become pregnant, only a small proportion implement nutrition and lifestyle changes in the preconception period (Inskip, Crozier, Godfrey, Borland, & Robinson, 2009
). Healthy eating patterns, body weight, folic acid supplementation, and other nutrition concerns are addressed in the following sections.
Healthy Eating Patterns
The basic principles of healthy eating that apply to healthy people are also appropriate before, during, and after pregnancy: Consume a calorie-appropriate eating pattern that includes plenty of fruits and vegetables of various kinds and colors; whole-grain bread and cereals; a variety of lean protein foods; low-fat or fat-free dairy products; and healthy oils in moderation. As with the general public, sodium, solid fats, added sugars, and refined grains should be limited. Nutrient needs should be met primarily through food, not supplements. Evidence suggests that healthy eating patterns prior to conception such as the Mediterranean-style eating pattern (Chapter 8
) and the Dietary Approaches to Stop Hypertension (DASH) eating pattern (Chapter 20
) are associated with a 24% to 48% lower risk of gestational diabetes (Tobias et al., 2012
Common to both of these patterns are a high intake of fruit, vegetables, whole grains, and nuts and legumes, and a low intake of red and processed meats. It is likely that several potential mechanisms are responsible for the lower gestational diabetes mellitus (GDM) risk, including benefits related to weight, insulin resistance, and antioxidant content.
In the United States, more than half of pregnant women are overweight or obese (American College of Obstetricians and Gynecologists [ACOG], 2013b
). Achieving a healthy weight
prior to conception reduces the risk of neural tube defects, preterm delivery, diabetes, cesarean section, and hypertensive and thromboembolic diseases associated with obesity (Centers for Disease Control and Prevention [CDC], 2014c
). All women with a BMI of 18.5 or lower or 25 or higher should be counseled about the risks of unhealthy weight to maternal health and future pregnancies, including the risk of infertility. Clinical care recommendations are based on BMI (CDC, 2014c).
Healthy Weight BMI of 18.5 to 24.9.
The World Health Organization (WHO, 2012), Institute of Medicine (IOM, 1998
), CDC (2014c), U.S. Preventive Services Task Force (USPSTF, 2009), and 2015-2020 Dietary Guidelines for Americans
(U.S. Department of Health and Human Services [USDHHS] & U.S. Department of Agriculture [USDA], 2015
) are among the many experts who recommend that synthetic folic acid
be consumed prior to conception to prevent neural tube defects. Because neural tube defects
originate in the first month of pregnancy before a woman may even know she is pregnant, all women of childbearing age who are capable of becoming pregnant are urged to consume 400 mg of synthetic folic acid every day from fortified food or supplements in addition to consuming natural folate
in a varied eating pattern. Synthetic folic acid is recommended because it is better absorbed and has greater availability than natural folate in foods.
Folic Acid synthetic form of folate found in multivitamins, fortified breakfast cereals, and enriched grain products.
Neural Tube Defect a serious central nervous system birth defect, such as anencephaly (absence of a brain) and spina bifida (incomplete closure of the spinal cord and its bony encasement).
Folate natural form of the B vitamin involved in the synthesis of DNA; only one-half is available to the body as synthetic folic acid.
Other Nutrition Concerns
Because of the high prevalence of iron deficiency anemia among menstruating women, screening for anemia is recommended prior to conception. Counseling should include dietary sources of heme iron and how certain foods promote nonheme iron absorption (e.g., orange juice, meat), whereas others impair nonheme iron absorption (e.g., tea, coffee). Screening should also identify all supplements used, including vitamins, minerals, herbs, weight loss products, and home remedies so that safety and efficacy can be discussed.
NUTRITION AND LIFESTYLE DURING PREGNANCY
Epidemiologic evidence suggests that intrauterine environment plays a significant role in the origins of adult disease, including in utero programming of obesity and diabetes (Barker, 1990
; Oken & Gillman, 2003
). Many women are motivated during pregnancy to adopt healthy lifestyle changes, which have the potential to make a long-lasting impact on the health of mother and infant. Counseling on healthy weight and lifestyle should ideally start before conception or as soon as pregnancy is confirmed, particularly to prevent excess fat development in the fetus, infant, and adult (Davenport, Ruchat, Giroux, Sopper, & Mottola, 2013
). Best practices for nutrition care are outlined in the following sections.
Recommended Amount and Pattern of Weight Gain
Current weight gain recommendations for pregnancy are based on prepregnancy BMI (see Table 11.1
). Recommended weight gain is 25 to 35 pounds in women of normal weight, 28 to 40 pounds for underweight women, 15 to 25 pounds for overweight women, and 11 to 20 pounds for women who are obese at the time of conception (IOM, 2009). Although record numbers of American women have BMI values ≥35, the IOM (2009) stated there was insufficient data available to issue specific weight gain recommendations for this population. Recent data suggest that women with a BMI ≥40 who lose weight during pregnancy have a decreased risk of adverse birth outcomes compared to women who gained within the IOM recommendations (Blomberg, 2011
). Women pregnant with twins need to gain somewhat more weight than that recommended for single births but not double the amounts.
Regardless of prepregnancy BMI, it is recommended that all women gain 1 to 4 pounds in the first trimester; thereafter, weekly weight is based on prepregnancy BMI (see Table 11.1
). Normal-weight women are urged to gain approximately 1 pound per week during the second and third trimesters; recommended amounts of weekly gain for underweight, overweight, and obese women are slightly different (see Table 11.1
) (IOM, 2009). Although slightly higher or lower rates of weight gain can be considered normal, obvious or persistent deviations warrant further investigation.
Table 11.1 Recommended Weight Gain Ranges Based on Maternal Prepregnancy Body Mass Index (BMI)
Prepregnancy BMI Status
Total Weight Gain (pounds)
Rate of Weekly Weight Gain in Second and Third Trimester (mean range in pounds per week)*
Less than 18.5
30 or greater
Obese (all classes)
* Calculations assume 1.1- to 4.4-pound weight gain in the first trimester.
Source: National Research Council. (2009). Weight gain during pregnancy: Reexamining the guidelines. Washington, DC: The National Academies Press.
According to Dietary Reference Intakes (DRIs), pregnant women do not need any additional calories until the second trimester. Even then, the increase is surprisingly small: An extra 340 cal/day is recommended during the second trimester and an additional 452 cal/day in the third (IOM, 2005). Most women of healthy prepregnancy weight need a total of 2200 to 2900 cal/day (Lessen & Kavanagh, 2015
). Throughout pregnancy, adequacy of calorie intake is measured by adequacy of weight gain.
Healthy Eating Pattern
The foundation of a healthy eating pattern—as presented during preconception—is consistent throughout the lifespan, including during pregnancy. For pregnant women, choosing a variety of nutrient-dense foods within each food group is especially important so that the increase in nutrient needs can be met without exceeding the relatively small increase in calories recommended during the second and third trimesters.
A tool to help pregnant women choose a calorie-appropriate healthy eating pattern is MyPlate Daily Checklist for Moms (www.choosemyplate.gov/moms-daily-food-plan
). For ease of use, patterns generated for pregnant women of healthy body weight increase by 400 cal/day beginning in the second trimester and lasting through the course of pregnancy. Figure 11.1
features eating patterns for a woman whose nonpregnant calorie requirements are 2000 cal/day. Notice the increase in food recommended during the second and third trimesters is relatively small, with a daily increase of
Additionally, although not part of the traditional food groups, oil allowance increases by 4 g/day, and an additional 80 calories are allotted for solid fat, added sugar, or more food from any of the food groups.
▶ Sample MyPlate Daily.
Checklists During Pregnancy and Lactation. (Source: U.S. Department of Agriculture, Center for Nutrition Policy and Promotion. . Available at www.choosemyplate.gov. Accessed on 4/8/16.)
Although most nutrient requirements increase during pregnancy (Table 11.2
Nutrient needs are not constant throughout the course of pregnancy. Nutrient needs generally change little during the first trimester (folic acid is an exception) and are at their highest during the last trimester.
Nutrient needs do not increase proportionately. For instance, the need for iron increases by 50% during pregnancy, yet the requirement for vitamin B12 increases by only about 10%.
Actual requirements during pregnancy vary among individuals and are influenced by previous nutritional status and health history including chronic illnesses, multiple pregnancies, and closely spaced pregnancies.
The requirement for one nutrient may be altered by the intake of another. For instance, women who do not meet their calorie requirements need higher amounts of protein.
The intake of more food to meet increased calorie requirements and the increase in absorption and efficiency of nutrient use that occurs in pregnancy are generally enough to meet nutrient needs when healthy food choices are made (Lessen & Kavanagh, 2015
). Exceptions are discussed in the following section.
Folic acid has a vital role in DNA synthesis and thus is essential for the synthesis of new cells and transmission of inherited characteristics. Synthetic folic acid in fortified food and supplements is better absorbed than folate that occurs naturally in foods. It is recommended that before and during pregnancy, women consume a total of 600 µg of dietary folate equivalents (DFE) daily of which 400 mg is from a supplement or fortified food and the remaining amount is folate naturally present in food.
Dietary Folate Equivalents (DFE) a measure of total folate available that accounts for the lower availability of natural folate in food compared to synthetic folic acid used in fortified foods and supplements. Total DFE = micrograms of food folate + 1.7 × micrograms of synthetic folic acid.
Table 11.2 Selected Nutritional Needs for Women (Aged 19-30 Years) During Pregnancy and Lactation
1st tri: +0
2nd tri: +340
1st 6 months: +330
3rd tri: +450
2nd 6 months: +400
Vitamin A (µg)
Vitamin C (mg)
Vitamin D (IU)
Vitamin E (mg)
Vitamin K (µg)*
Vitamin B6 (mg)
Vitamin B12 (µg)
Recommended Dietary Allowances are in boldface; Adequate Intakes (AIs) appear in roman type followed by an asterisk (*). tri, trimester.
The Recommended Dietary Allowance (RDA) for iron increases from 18 to 27 mg/day during pregnancy to support the increase in maternal blood volume and to provide iron for fetal liver storage, which sustains the infant for the first 4 to 6 months of life. Even with careful selections, women are not likely to consume adequate amounts of iron during pregnancy from food alone. Most prenatal vitamins contain 30 mg of elemental iron. Prenatal supplementation with daily iron effectively lowers the risk of LBW and maternal anemia (Peña-Rosas, De-Regil, Dowswell, & Viteri, 2012
); intermittent supplementation (one to two times a week) has also been shown effective in reducing maternal anemia or iron deficiency (Peña-Rosas & Viteri, 2009
Vitamin and mineral supplements may be necessary for certain populations, such as women who (Kaiser & Campbell, 2014
Specific vitamin and mineral supplements that may be needed based on individual circumstances are as follows:
Pregnant women who consume little or no animal products should take a supplement of vitamin B12 if a reliable dietary source is not consumed. Reliable sources are vegan foods fortified with vitamin B12, such as yeast extracts, vegetable stock, veggie burgers, textured vegetable protein, soymilk, vegetable and sunflower margarines, and ready-to-eat breakfast cereals.
The RDA for calcium does not increase during pregnancy because the rate of absorption and maternal bone calcium mobilization increases (Procter & Campbell, 2014
). However, women who consume less than 500 mg calcium per day may need supplements to meet maternal and fetal bone requirements (Procter & Campbell, 2014
Women who do not consume adequate vitamin D or have insufficient sunlight exposure are at risk of vitamin D deficiency. The ACOG (2011) maintains that supplements of 1000 to 2000 IU per day are probably safe for pregnant women who are vitamin D deficient.
Zinc supplementation may be advisable in women who have impaired zinc absorption secondary to a plant-based eating pattern that is high in phytates, GI disorders, or use of high doses of supplemental iron.
Because little is known about the safety and efficacy of herbal supplements during pregnancy, it is recommended that they not be used during pregnancy and lactation. Herbal products, including herbal teas, are technically unapproved drugs; most drugs cross the placental barrier to some degree, exposing the fetus to potentially teratogenic effects. Unlike approved drugs, little animal or human testing has been done to determine if herbs can cause birth defects or potentially harm mothers and infants.
Alcohol use during pregnancy can cause physical and neurodevelopmental problems, such as mental retardation, learning disabilities, and fetal alcohol syndrome. Alcohol does its damage by dehydrating fetal cells, leaving them dead or functionless, or by causing secondary nutrient deficiencies. Because alcohol is a potent teratogen and a “safe” level of consumption is not known, women are advised to completely avoid alcohol before and during pregnancy.
Fetal Alcohol Syndrome a condition characterized by varying degrees of physical and mental growth failure and birth defects caused by maternal intake of alcohol.
Teratogen anything that causes abnormal fetal development and birth defects.
The half-life of caffeine increases during pregnancy from 3 hours in the first trimester to 80 to 100 hours in late pregnancy (Procter & Campbell, 2014
). Results of studies are mixed on the effect of caffeine on the risk of adverse pregnancy outcomes (Brent, Christian, & Diener, 2011
; Hoyt, Browne, Richardson, Romitti, & Druschel, 2014
). The ACOG (2010) recommends pregnant women limit their intake of caffeine to less than 200 mg/day, which is the approximate amount in 16 oz of coffee (Table 11.3
Table 11.3 Caffeine Content of Selected Beverages and Foods
Average Caffeine Content (mg)
Starbucks brewed (grande)
Brewed, leaf or bag
Snapple iced tea (all flavors)
Dr. Pepper, Sunkist Orange
Club soda, ginger ale, 7Up, Squirt, tonic water, Sprite
Sobe No Fear
Chocolate milk or hot cocoa
Yoo-hoo chocolate drink
Dark chocolate, semisweet
Sources: Adapted from U.S. Department of Agriculture, Agricultural Research Service. (2005). USDA National Nutrient Database for Standard Reference, Release 18. Available at www.ars.usda.gov/northeast-area/beltsville-md/beltsville-human-nutrition-research-center/nutrient-data-laboratory/docs/sr18-home-page/; Center for Science and the Public Interest. (2014). Caffeine content of foods and drugs. Available at www.cspinet.org/new/cafchart.htm. Accessed on 4/9/16; and McCusker, R. R., Goldberger, B. A., & Cone, E. J. (2006). Caffeine content of energy drinks, carbonated sodas, and other beverages. Journal of Analytical Toxicology, 30, 112-114.
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