NUTRITION MANAGEMENT DURING PREGNANCY AND LACTATION

Description
Diets for pregnant and lactating women include additional servings of food from the Regular Diet to meet the increased requirement for nutrients during pregnancy and lactation.

Nutritional Adequacy
The food patterns given will meet the Dietary Reference Intakes (DRIs) for pregnancy and lactation, as outlined in the Statement on Nutritional Adequacy, except for iron during the second and third trimesters of pregnancy.  Factors that may increase nutritional requirements above the estimated demands of pregnancy include poor nutritional status; young maternal age; multiple pregnancy; closely spaced births; breast-feeding one or more children during pregnancy; continued high level of physical activity; certain disease states; and use of cigarettes, alcohol, and legal or illegal drugs.  Dietary intake of iron, folate, zinc, protein, and calcium should be carefully assessed for adequacy (1).  Supplementation is justified when evidence suggests inadequate intake of specific nutrients that increase the risk of an adverse effect on the mother, fetus, or pregnancy outcome.  Vegetarians who exclude all animal products need 2 mg of vitamin B12 daily (1).

How to Order the Diet
Order as “Regular Diet – Pregnancy” or “Regular Diet – Lactation.”  Any special instructions should be indicated in the diet order.

Planning the Diet

Daily Food Group Guidelines (2)
	No. of Servings
Food Group	Pregnant	Lactating
Grains, Breads, and Cereals	9	6-11
Fruits	3	2 -4
Vegetables	4	3-5
Low-fat Meat, Poultry, Fish, and Eggs	2 or more (6 oz)	2 or more (7-8 oz)
Low-fat Milk, Yogurt, Cheese	3-4	4-5
Fats, Oils, and Sweets	As needed to provide energy

Specific Nutrient Requirements During Pregnancy
Weight gain during pregnancy: The National Academy of Sciences’ Food and Nutrition Board (FNB) has stated that the optimal weight gain during pregnancy depends on the mother’s weight at the beginning of pregnancy (1).  The target range for weight gain is associated with a full-term, healthy baby, weighing an average of 3 to 4 kg (6.6 lb to 8.8 lb) (3).  The optimum weight gain for a woman of normal prepregnancy weight, for her height, carrying a single fetus is suggested at 25 to 35 lbs, however individual differences vary based on maternal anthropometry and ethnic decent (3).  The pattern of weight gain is of greater significance than the absolute weight gain.  The desired pattern of weight gain is approximately 3 to 8 lb in the first trimester and about 1 lb per week during the last two trimesters. 

    Body mass index (BMI), defined as weight/height squared (kg/m2) (2), is a better indicator of maternal nutritional status than is weight alone.  Recommendations for weight gain during pregnancy should be individualized according to prepregnancy body mass index.  See Body Mass Index.  To identify the weight for height categories and appropriate weight gain, use Table A-1 (1).

Table A-1             Guidelines for Weight Gain After the First Trimester of Pregnancy (1,4)
BMI	Recommended Rate of Weight Gain	Intervention Suggested	Overall Weight Gain
<19.8 (underweight)	1 lb/wk	<2 lb/mo	28-40 lb
19.8-26 (normal weight)	1 lb/wk	<2 lb/mo >6.5 lb/mo	25-35 lb
>26-29 (overweight)	0.66 lb/wk	>3.5 lb/wk <1 lb/wk	15-25 lb
>29 (obese)	Individualized	<l lb/wk >2.5 lb/wk	15 lb
Twins	1.5 lb/wk	Individualized	34-45 lb
Triplets	Individualized	Individualized	50 lb

    Women with a height under 62 inches should strive for a weight gain at the lower end of the range (2). For twins, a woman should gain 35 to 45 lb (or a rate of 0.7 kg/week after the first trimester); for triplets, more than 50 lb (4).

    On average, each successive birth contributes an additional 2 lb above that normally gained with age.  However, women with high gestational weight gains may surpass this average (1).

    Energy: The total energy needs during pregnancy range between 2,400 and 2,800 kcal/day for most women (3,5).  However, the mother’s age, pre-pregnant BMI, rate of weight gain, and physiologic appetite must be considered in determining individual needs (3).  Based on the review of evidence, the average additional intake of approximately 300 kcal/day is suggested after the first trimester in addition to normal energy needs (5,6).  For normal and overweight women in developed countries, the additional energy need may actually be less than the 300 kcal/day usually recommended, especially in sedentary women (3).  Appropriate weight gain and appetite are better indicators of energy sufficiency than the amount of energy (calories) consumed (3). The additional 500 kcal/day for a twin pregnancy after the first trimester are added to calculated needs.  There is no absolute recommendation in the literature for the number of additional calories for a multiple pregnancy.  The indication is to add 500 kcal/day in the first trimester as soon as the multiple pregnancy is diagnosed, as these pregnancies usually do not go to term and the goal is to maximize the weight gain early (4).    

    Protein: The 2002 DRIs list the Recommended Daily Allowances (RDA) for protein for all age groups during pregnancy and lactation to be 1.1 g/kg per day of protein or an additional 25 g/day of protein in addition to the 0.8 g/kg per day for a nonpregnant state (5).  On average this equates to approximately 71 g, but for some women with greater energy needs, protein needs may need to be adjusted.  For twin pregnancy, an additional 50 g/day of protein above the RDA of 0.8 g/kg per day for a nonpregnant state is suggested during the second and third trimesters (5).  Protein utilization depends on energy intake.  Therefore, adequate energy intake is important so that protein may be spared.

    Vitamins and minerals: A multivitamin and mineral supplement is recommended during pregnancy in several circumstances (1,3).  Pregnant women who smoke or abuse alcohol or drugs should take a multivitamin and mineral supplement (3).  A multivitamin and mineral supplement is also recommended for women with iron deficiency anemia or poor-quality diets and for those who consume animal products rarely or not at all (3).  B12 supplementation is recommended in persons who follow a vegetarian diet pattern (3).  Additional nutrients that may require the need for supplementation include folic acid, iron, zinc, copper, and calcium.  The Nutrition Board recommends supplements or fortified foods be used to obtain desirable amounts of some nutrients, such as iron, and recommends 400 mg/day of synthetic folic acid from fortified foods, supplements, or both in persons wanting to become pregnant, and 600 mg/day for persons who are pregnant (7).

    Iron: So that a woman meets the required additional 30 mg of ferrous iron per day during pregnancy, a low-dose supplement is recommended beginning with the first prenatal visit (1,3,6).  An iron supplement containing 150 mg of ferrous sulfate, 300 mg of ferrous gluconate, or 100 mg of ferrous fumarate can provide this additional need.  Iron deficiency anemia is the most common anemia during pregnancy.  If the maternal iron stores are low, 60 to 120 mg of iron may be recommended (4), in addition to a multivitamin supplement containing 15 mg of zinc and 2 mg of copper, since iron may interfere with absorption of zinc and copper (3).  If the laboratory values indicate macrocytic anemia, vitamin B12 and folate levels should be assessed (1).

    Zinc and copper: Iron can interfere with the absorption of other minerals.  Therefore, women taking supplements with more than 30 mg of iron a day should add 15 mg of zinc and 2 mg of copper (3).  These amounts of zinc and copper are routinely found in prenatal vitamins.   

    Folate: The DRI for folate for women 19 to 50 years of age is 600 mg/day (7-8).  This level of folate is to be consumed through synthetic folic acid from fortified food or supplements or both, in addition to intake of folate from a varied diet (3,6).  Compared to naturally occurring folate found in foods, the folic acid contained in fortified foods and supplements is almost twice as well absorbed, so that 1 mg from these sources is equivalent to 1.7 mg dietary folate equivalents (3).  Studies have documented that women taking folic acid at the time of conception are less likely to give birth to a child with neural tube defects (9-12).  To ensure that blood vitamin levels are adequate at the time of neural tube closure, supplementation should begin at least 1 month before conception (3).  It also has been reported that women taking multivitamins containing folic acid 1 to 2 months before conception have a reduced risk of having a child with orofacial clefts (13).  Research also indicates that abnormal folate metabolism may play a role in Down syndrome and other birth defects (3).  It has been suggested that women who have delivered an infant with neural tube defects may need to consume more than the recommended amount of dietary folate equivalents (3).  Until more information becomes available, it is recommended that women older than 19 years of age not exceed the tolerable upper limit of 1,000 mg/day of folate from foods, fortified foods, and supplements (3).

    Calcium: Due to the increased efficiency of calcium absorption, calcium requirements are similar to those in the nonpregnant state.  A daily intake of 1000 mg is recommended for pregnant and lactating women (13) older than 19 years (<19 years, 1,300 mg/day) (13).

Sodium: Sodium is required during pregnancy for the expanding maternal tissue and fluid compartments and to provide fetal needs.  Routine sodium restriction is not recommended (6).

    Vitamin A: High doses of vitamin A during pregnancy have resulted in children with birth defects of the head, heart, brain, or spinal cord.  The Food and Drug Administration (FDA) and the Institute of Medicine recommend that vitamin A intake be limited to DRIs of 5,000 IU during pregnancy (14-16).  In addition, pregnant women should limit their intake of liver and fortified cereals.  The FDA recommends that women of childbearing age choose fortified foods that contain vitamin A in the form of beta carotene rather than preformed vitamin A whenever possible.  A high intake of fruits and vegetables rich in beta carotene and other carotenoids is not a concern (15).

    Fluids: Adequate fluid intake is extremely important.  It is recommended that pregnant women drink 8 to 10 cups of water and other fluids a day or 35 to 40 mL/kg of pregravid weight (3,17).

    Fiber: Ingestion of fiber is important to speed digestion and help prevent constipation and hemorrhoids.  The 2002 DRI for Adequate Intake (AI) of total fiber is 28 g/day for all age groups during pregnancy(5). 

Other Substances
Alcohol: The consumption of alcohol during pregnancy may result in fetal alcohol syndrome (FAS).  Studies suggest that even light to moderate drinking may cause neurologic abnormalities not detectable at birth.  Since a safe level has not been determined, it is recommended that pregnant women abstain from alcohol (3,18).

    Caffeine: Studies on caffeine consumption are inconclusive.  Caffeine can readily cross the placenta and can affect fetal heart rate and breathing (3).  Some studies have found no adverse effects as a result of moderate caffeine consumption, while others noted an increase in stillbirths, spontaneous abortions, and malformations in pregnant women who consumed high levels of caffeine (>300 to 500 mg/day) (19-21).  Until further evidence provides guidelines for setting a specific limit on caffeine intake, it is recommended to limit caffeine during pregnancy to moderate consumption (<200 mg/day) (2,19-21).

    Olestra: Studies of the fat substitute olestra conclude that pregnant or breast-feeding women should not consume products containing olestra.  Olestra has been shown to cause gastrointestinal distress and diarrhea, which may lead to the loss of the necessary fat-soluble vitamins A, D, E, and K (22).

    Sugar substitutes: The FDA has approved five nonnutritive sweeteners for general use: saccharin, aspartame, acesulfame-K, neotame, and sucralose.  The studies on the effects of these sweeteners on reproductive abilities in females and males as well as on the developing fetus have been reviewed and deemed safe by numerous regulatory bodies and expert communities around the world (23). Thus, consumption of acesulfame-K, aspartame, saccharin, sucralose, and netotame within the acceptable daily intakes is safe during pregancy (23).  Research continues to indicate that aspartame is safe during pregnancy, although women with phenylketonuria should exercise caution with this sweetener because they need to monitor their intake of phenylalanine closely (3,23).  There is limited evidence that saccharin can pass through the placenta and that it remains in fetal tissues; therefore, women should moderate their intake of this sweetener (3).  Acesulfame K crosses the placenta, but it has shown no adverse effect on the fetus and is considered safe (23). 

    Herbal and alternative therapies: Very few randomized clinical trials have examined the safety and efficacy of alternative therapies during pregnancy (3).  Several identified herbal and botanical supplements have been identified to be harmful if used during pregnancy (3).  The American Academy of Pediatrics recommends that pregnant women limit the consumption of herbal teas.  If women opt to consume herbal teas, it is recommended to limit intake to two 8-oz servings per day and to choose herbal teas in filtered tea bags (3).

Risk Factors During Pregnancy (1,21)
Women should be evaluated for factors that may put them at risk while they are pregnant.  If any of the following risks are identified, appropriate medical and nutritional monitoring should be provided throughout the pregnancy.

Risk factors at the onset of pregnancy:

Adolescence:  younger than 15 years at time of conception or less than 3 years of age since onset of menses	Unusual dietary practices Smoker Excessive alcohol intake
Older than 35 years of age	Recreational drug usea
Three or more pregnancies within 2 years	Chronic systemic disease
History of poor obstetric or fetal performance Economic deprivation	Pre-pregnancy BMI under 19.8 or over  29 Multiple gestation
aRecreational drug use or use of over-the-counter medications or dietary supplements having adverse affects, eg, laxatives, antacids, or herbal remedies containing teratogens.

• Risk factors during pregnancy (1,21,24):
• Hemoglobin level <11 g/dL (first and third trimesters); <10.5 g/dL (second trimester); or hematocrit below 33% (first and third trimesters), <32% (second trimester)
• Inadequate weight gain:   
  • Below 1 lb/month for very overweight women
  • Below 2 lb/month for normal or slightly overweight women
  • Below 4 to 8 lb/month for women with multiple gestation and underweight women                                                       
• Excessive weight gain (more than 6.6 lb/month after first trimester), possibly associated with fluid retention
• Ferritin below 20 mg/dL (24)
• Serum folate level below 3 mg/dL
• Serum albumin level below 2.5 g/dL
• Total serum protein level below 5.5 g/dL
• Vitamin B12 level below 80 pg/mL

Nausea and Vomiting of Pregnancy
Nausea and vomiting, known as nausea and vomiting of pregnancy (NVP), are the most common symptoms experienced in early pregnancy, with nausea affecting 70% to 85% of women, and about 50% experiencing vomiting (25).  Current recommendations for managing nausea include consumption of lemonade, potato chips, or foods with a mild salt flavor (26).  Increased olfactory senses often are the leading cause of nausea during early pregnancy and can be minimized by avoiding strong or sensitive odors (26).  Other management techniques include the following:

• Eat small frequent meals and snacks
• Eat low-fat protein foods and easily digested carbohydrate foods
• Eat dry crackers before rising in the morning
• Avoid spicy food and gas-forming fruits and vegetables
• Drink fluids between meals
• Avoid drinks with caffeine and alcohol

    When nausea and vomiting are persistent and severe, causing dehydration, fluid and electrolyte abnormalities, acid-base disturbances, weight loss, and ketonuria, a diagnosis of hyperemesis gravidarum is made (27-29).  Hyperemesis gravidarum (HG) occurs in approximately 1% to 2% of pregnant women (27).  Studies indicate that women with hyperemesis have similar demographic characteristics to the general obstetric population (racial status, marital status, age, and gravidity) (30).  The pathogenesis of HG is not well understood.  Potential causes include hormonal changes, thyroid changes (eg, hyperthyroidism), bacterial infection (eg, underlying Helicobacter pylori infection), and increasing levels of human chorionic gonadotrophin (27,31,32).

    Often HG spontaneously resolves after the first trimester (27).  Treatment depends on the risk level of the patient and severity of symptoms, such as the inability to meet nutrition needs orally and dehydration.  Intensive nutrition counseling and individualized meal planning is the first line of treatment (25-33).  In patients in whom nutrition and behavior modification does not alleviate symptoms, medication is often prescribed, such as metoclopramide (Reglan), ranitidine (Zantac), prochlorperazine (Compazine), and ondansetron (Zofran) (27).  In patients whose symptoms are severe, hydration with intravenous fluids, electrolyte replacement, and in some cases vitamin replacement is needed (27,31,32).  Nutrition interventions for severe hyperemesis gravidarum may include nasogastric, gastrostomy, and jejunostomy feedings or total parenteral nutrition (TPN).  The percentage of women requiring TPN is low but varies from 2% to 5% (27).  Nearly all of the literature regarding nutrition support during pregnancy is anecdotal, consisting of case studies.  Treatment and intervention strategies are based on experience and patient needs.  If nutrition support is indicated, treatment is consistent with standards outlined for nonpregnant adults or in managing coexisting disease states, as outlined in Specialized Nutrition Support and as outlined in Specific Nutrient Requirements During Pregnancy.

Pregnancy-Induced Hypertension (3,16-18)
Hypertension (>140mg systolic blood pressure or >90 mg diastolic blood pressure), proteinuria ( >300mg/24 hour) (34), and edema characterize pregnancy-induced hypertension (PIH), also called preeclampsia.  Preeclampsia occurs more often in primigravid women and in women over 35 years old with chronic hypertension and/or renal disease.

    Pregnancy-induced hypertension is associated with marked changes in renal function that may lead to excessive extracellular fluid retention.  When PIH is accompanied by convulsions, it is called eclampsia.  Preeclampsia usually occurs after the 20th week of conception.  It is more common in women with chronic hypertension, and renal disease, and among adolescents, underweight women who fail to gain weight properly, women from low-income populations, and women carrying multiple fetuses.

    No specific nutrition therapy has been proven to be effective in preventing or delaying preeclampsia and improving pregnancy outcomes (3,34).  Adequate calcium, protein, energy, and potassium may be necessary.  A meta-analysis of 17 randomized controlled trials concluded that calcium supplements (1 to 2 g/day) reduced blood pressure and the risk of preeclampsia but had no significant effect on reducing maternal and infant morbidity and mortality (35).  Other nutrients have been studied (eg, vitamins C and E); however, inconclusive results were found.  Dietary modifications, including sodium restriction, magnesium supplements, zinc supplements, and consumption of fatty fish oils have not been proved effective (3).  Diuretics should be avoided unless given under strict medical supervision.

Specific Nutrient Requirements During Lactation
    Energy:  The average energy costs of lactation are an additional 500 kcal/day (5) in the first 6 months and 400 kcal/day in the second 6 months (5).  Excessive restriction of energy may compromise milk production.  Consumption of less than 1800 kcal/day may result in a decrease in milk production.  

    Fluids: Intake of 2 to 3 qt of fluid daily is encouraged to compensate for the volume of milk produced.

    Alcohol: Discourage consumption of alcohol unless permitted by the physician.

    Caffeine: Limit consumption to two 5-oz cups of coffee (<200 mg) daily (16,21). 

    Fiber:  The 2002 DRI for Adequate Intake of total fiber is 29 g/day for all age groups during lactation (5).

References

1. Subcommittee on Nutritional Status and Weight Gain During Pregnancy, Committee of Nutritional Status During Pregnancy and Lactation, Food and Nutrition Board, Institute of Medicine, National Academy of Sciences: Nutrition During Pregnancy.  Washington, DC: National Academy Press; 1992.
2. Food Guide Pyramid: A Guide to Daily Food Choices. Washington, DC: US Dept of Agriculture, Human Nutrition Information Service. Home and Garden Bulletin No. 252.
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