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Position of the Academy of Nutrition and Dietetics: Nutrition and Lifestyle for a Healthy Pregnancy Outcome

      Abstract

      It is the position of the Academy of Nutrition and Dietetics that women of childbearing age should adopt a lifestyle optimizing health and reducing risk of birth defects, suboptimal fetal development, and chronic health problems in both mother and child. Components leading to a healthy pregnancy outcome include healthy prepregnancy weight, appropriate weight gain and physical activity during pregnancy, consumption of a wide variety of foods, appropriate vitamin and mineral supplementation, avoidance of alcohol and other harmful substances, and safe food handling. Pregnancy is a critical period during which maternal nutrition and lifestyle choices are major influences on mother and child health. Inadequate levels of key nutrients during crucial periods of fetal development may lead to reprogramming within fetal tissues, predisposing the infant to chronic conditions in later life. Improving the well-being of mothers, infants, and children is key to the health of the next generation. This position paper and the accompanying practice paper (www.eatright.org/members/practicepapers) on the same topic provide registered dietitian nutritionists and dietetic technicians, registered; other professional associations; government agencies; industry; and the public with the Academy's stance on factors determined to influence healthy pregnancy, as well as an overview of best practices in nutrition and healthy lifestyles during pregnancy.
      Position Statement
      It is the position of the Academy of Nutrition and Dietetics that women of childbearing age should adopt a lifestyle optimizing health and reducing risk of birth defects, suboptimal fetal development, and chronic health problems in both mother and child. Components leading to healthy pregnancy outcome include healthy prepregnancy weight, appropriate weight gain and physical activity during pregnancy, consumption of a wide variety of foods, appropriate vitamin and mineral supplementation, avoidance of alcohol and other harmful substances, and safe food handling.
      This position paper provides Academy of Nutrition and Dietetics members, other professional associations, government agencies, industry, and the public with the Academy's stance on factors determined to influence healthy pregnancy, as well as emerging factors. Women with inappropriate weight gain, hyperemesis, multiple gestations, poor dietary patterns (eg, disordered eating), or chronic disease should be referred to a registered dietitian nutritionist (RDN) for medical nutrition therapy. For specific practice recommendations, refer to the Academy's practice paper on “Nutrition and Lifestyle for a Healthy Pregnancy Outcome.”

      Academy of Nutrition and Dietetics. Practice Paper of the Academy of Nutrition and Dietetics: Nutrition and lifestyle for a healthy pregnancy outcome. http://www.eatright.org/members/practicepapers/. Published July 1, 2014. Accessed May 22, 2014.

      Trends Impacting Pregnancy Outcomes

      Birth Defects, Low Birth Weight, and Viable Birth Trends

      Pregnancy is a critical period during which maternal nutrition and lifestyle choices are major influences on mother and child health. Improving the well-being of mothers, infants, and children is key to the health of the next generation. One in 33 babies (approximately 3%) is born with a birth defect

      Centers for Disease Control and Prevention. Division of Birth Defects and Developmental Disabilities. Birth defects. http://www.cdc.gov/ncbddd/birthdefects/index.html. Accessed October 4, 2012.

      ; in 2010, low-birth-weight (LBW) infants comprised 8.1% of US births.

      Centers for Disease Control and Prevention. FastStats: Births and natality. http://www.cdc.gov/nchs/fastats/births.htm. Accessed October 4, 2012.

      Birth defects and LBW are ranked first and second, respectively, among the 10 leading causes of death in US infants in 2006.

      Centers for Disease Control and Prevention. FastStats: Births and natality. http://www.cdc.gov/nchs/fastats/births.htm. Accessed October 4, 2012.

      A woman's chance of having a healthy baby improves when she adopts healthy behaviors, including good nutrition; recommended supplementation; and avoidance of smoking, alcohol, and illicit drugs before becoming pregnant.

      Centers for Disease Control and Prevention. Division of Birth Defects and Developmental Disabilities. Birth defects. http://www.cdc.gov/ncbddd/birthdefects/index.html. Accessed October 4, 2012.

      Obesity and Gestational Diabetes

      Prepregnancy body mass index (BMI) is an independent predictor of many adverse outcomes of pregnancy. The prevalence of obesity in women 12 to 44 years of age has more than doubled since 1976. In 1999 to 2004, nearly two thirds of women of childbearing age were classified as overweight (BMI ≥25) and almost one third were obese (BMI ≥30).
      Overconsumption/overweight throughout the reproductive cycle are related to short- and long-term maternal health risks, including obesity, diabetes, dyslipidemia, and cardiovascular disease. Caloric excess does not guarantee adequate intake or nutrient status critical to healthy pregnancy outcomes.
      • Shapira N.
      Prenatal nutrition: A critical window of opportunity for mother and child.
      To improve maternal and child health outcomes, women should weigh within the normal BMI range when they conceive and strive to gain within ranges recommended by the Institute of Medicine (IOM) 2009 pregnancy weight guidelines.
      High rates of overweight and obesity are common in population subgroups already at risk for poor maternal and child health outcomes, compounding the need for intervention.
      In addition to health risks, gestational weight gain beyond the recommendation substantially increases risk of excess weight retention in obese women at 1 year postpartum.
      • Vesco K.K.
      • Dietz P.M.
      • Rizzo J.
      • et al.
      Excessive gestational weight gain and postpartum weight retention among obese women.
      More information on obesity and pregnancy outcomes can be found in the “Position of the Academy of Nutrition and Dietetics and American Society for Nutrition: Obesity, Reproduction, and Pregnancy Outcomes.”
      Academy of Nutrition and Dietetics
      Position of the Academy of Nutrition and Dietetics and American Society for Nutrition: Obesity, reproduction, and pregnancy outcomes.
      New diagnostic criteria for gestational diabetes mellitus (GDM) are expected to increase the proportion of women diagnosed with GDM, with potentially 18% of all pregnancies affected.

      Centers for Disease Control and Prevention. 2011 National Diabetes fact sheet: Gestational diabetes in the United States. http://www.cdc.gov/diabetes/pubs/estimates11.htm. Accessed November 11, 2012.

      Immediately after pregnancy, 5% to 10% of women with GDM are found to have diabetes, usually type 2. Women who have had GDM have a 35% to 60% chance of developing diabetes in the next 10 to 20 years.

      Centers for Disease Control and Prevention. 2011 National Diabetes fact sheet: Gestational diabetes in the United States. http://www.cdc.gov/diabetes/pubs/estimates11.htm. Accessed November 11, 2012.

      RDNs can provide valuable guidance to women seeking assistance regarding optimal weight and healthy food selection before, during, and post pregnancy. Additional information and guidance is available in the Academy's GDM Evidence-Based Nutrition Practice Guideline.

      Academy of Nutrition and Dietetics Evidence Analysis Library. Gestational diabetes evidence-based nutrition practice guideline. http://andevidencelibrary.com/topic.cfm?cat=3733. Accessed December 6, 2013.

      Hypertension and Preeclampsia

      Prevalence of chronic hypertension in pregnancy in the United States is estimated to be as high as 5%. This is primarily attributable to the increased prevalence of obesity, as well as delay in childbearing to ages when chronic hypertension is more common.
      • Seely E.W.
      • Ecker J.
      Chronic hypertension in pregnancy.
      Hypertension in pregnancy can harm both mother and fetus, and women with chronic hypertension are more likely to experience preeclampsia (17% to 25% vs 3% to 5% in the general population).
      • Seely E.W.
      • Ecker J.
      Chronic hypertension in pregnancy.
      Age, preconception weight and health status, access to timely and appropriate health care, and poverty are some of the numerous factors affecting maternal health and the likelihood of a healthy pregnancy. Referral to the RDN and/or social worker may assure appropriate care will be available, given the aforementioned factors that can influence maternal and fetal outcomes.

      Optimizing Pregnancy Outcomes with Healthy Lifestyle Choices

      Evidence is building that maternal diet and lifestyle choices influence the long-term health of the mother's children. Prepregnancy adherence to healthful dietary patterns, including the alternate Mediterranean Diet, Dietary Approaches to Stop Hypertension (DASH), and alternate Healthy Eating Index, have been associated with a 24% to 46% lower risk of GDM.
      • Tobias D.K.
      • Zhang C.
      • Chavarro J.
      • et al.
      Prepregnancy adherence to dietary patterns and lower risk of gestational diabetes.
      Population-based research provides evidence that maternal metabolic conditions may be associated with neurodevelopmental problems, including autism and developmental delays in children.
      • Krakowiak P.
      • Walker C.K.
      • Bremer A.A.
      • et al.
      Maternal metabolic conditions and risk for autism and other neurodevelopmental disorders.
      Inadequate levels of key nutrients during crucial periods of fetal development may lead to reprogramming within fetal tissues, predisposing the infant to chronic conditions in later life. Those conditions include obesity, cardiovascular disease, bone health, cognition, immune function, and diabetes.
      • Hanley B.
      • Dijane J.
      • Fewtrell M.
      • et al.
      Metabolic imprinting, programming and epigenetics—A review of present priorities and future opportunities.
      Maternal weight gain during pregnancy outside the recommended range is associated with increased risk to maternal and child health.
      Although physiological responses to prenatal overnutrition result in poor health outcomes that emerge in childhood and adolescence, fetal undernutrition responses range from fetal survival to poor health outcomes emerging later in the offspring's adult life.
      • McMillen I.C.
      • MacLaughlin S.M.
      • Muhlhausler B.S.
      • Gentili S.
      • Duffield J.L.
      • Morrison J.L.
      Developmental origins of adult health and disease: The role of periconceptional and foetal nutrition.
      The IOM recommends that more US women achieve gestational weight gain within the range identified for their prepregnant BMI.
      Pregnant women benefit from eating a variety of foods to meet nutrient needs and consuming sufficient calories to support recommended weight gain. Details regarding recommended energy requirements and recommended weight gain during pregnancy can be found in the related practice paper.

      Academy of Nutrition and Dietetics. Practice Paper of the Academy of Nutrition and Dietetics: Nutrition and lifestyle for a healthy pregnancy outcome. http://www.eatright.org/members/practicepapers/. Published July 1, 2014. Accessed May 22, 2014.

      Energy Expenditure

      Physical activity during pregnancy benefits a woman's overall health. In a low-risk pregnancy, moderately intense activity does not increase risk of LBW, preterm delivery, or miscarriage.
      US Department of Health and Human Services
      Physical activity for women during pregnancy and the postpartum period.
      Recreational moderate and vigorous physical activity during pregnancy is associated with a 48% lower risk of hyperglycemia, specifically among women with prepregnancy BMI <25.
      • Deierlein A.L.
      • Siega-Riz A.M.
      • Evenson K.R.
      Physical activity during pregnancy and risk of hyperglycemia.
      A prenatal nutrition and exercise program, regardless of exercise intensity, has been shown to reduce excessive gestational weight gain and decrease weight retention at 2 months postpartum in women of normal prepregnant BMI.
      • Ruchat S.M.
      • Davenport M.H.
      • Giroux I.
      • et al.
      Nutrition and exercise reduce excessive weight gain in normal-weight pregnant women.

      Appropriate and Timely Nutrient Supplementation

      Iron

      Iron deficiency with resultant anemia is the most prevalent micronutrient deficiency worldwide, affecting primarily pregnant or lactating women and young children.
      • Gautam C.S.
      • Saha L.
      • Sekhri K.
      • Saha P.K.
      Iron deficiency in pregnancy and the rationality of iron supplements prescribed during pregnancy.
      Iron-deficiency anemia in pregnant women in industrialized countries is 17.4%,
      • Khalafallah A.A.
      • Dennis A.E.
      Iron deficiency anaemia in pregnancy and postpartum: Pathophysiology and effect of oral versus intravenous iron therapy.
      with approximately 9% of adolescent girls and women of childbearing age in the United States having inadequate stores of body iron.
      US Department of Agriculture, US Department of Health and Human Services
      2010 US Dietary Guidelines Advisory Committee. Part D. Section 2: Nutrient adequacy.
      The high incidence of iron deficiency underscores the need for iron supplementation in pregnancy. During the first two trimesters of pregnancy, iron-deficiency anemia increases the risk for preterm labor, LBW, and infant mortality.
      • Gautam C.S.
      • Saha L.
      • Sekhri K.
      • Saha P.K.
      Iron deficiency in pregnancy and the rationality of iron supplements prescribed during pregnancy.
      Maternal and fetal demand for iron increases during pregnancy; this increase cannot be met without iron supplementation.
      • Gautam C.S.
      • Saha L.
      • Sekhri K.
      • Saha P.K.
      Iron deficiency in pregnancy and the rationality of iron supplements prescribed during pregnancy.

      Folic Acid

      Folic acid is recognized as important before and during pregnancy because of its preventive properties against neural tube defects. All women, including adolescents, who are capable of becoming pregnant should consume 400 μg/day folic acid from fortified foods and/or dietary supplements, in addition to eating food sources of folate.
      US Department of Agriculture
      US Department of Health and Human Services. Dietary Guidelines for Americans, 2010.
      Pregnant women are advised to consume 600 μg dietary folate equivalents daily from all food sources. Dietary folate equivalents adjust for the difference in bioavailability of food folate compared with synthetic folic acid. One dietary folate equivalent is equal to 1 μg food folate, which is equal to 0.6 μg folic acid derived from supplements and fortified foods taken with meals.
      • McMillen I.C.
      • MacLaughlin S.M.
      • Muhlhausler B.S.
      • Gentili S.
      • Duffield J.L.
      • Morrison J.L.
      Developmental origins of adult health and disease: The role of periconceptional and foetal nutrition.
      Women who have had an infant with a neural tube defect should consult with their health care provider regarding the recommendation to take 4,000 μg folic acid daily before and throughout the first trimester of pregnancy.

      Centers for Disease Control and Prevention. Folic acid: Recommendations. http://www.cdc.gov/ncbddd/folicacid/recommendations.html. Accessed September 24, 2012.

      An association between the lack of periconceptual use of vitamins or supplements containing folic acid with an excess risk for birth defects due to diabetes mellitus
      • Correa A.
      • Gilboa S.M.
      • Botto L.D.
      • et al.
      Lack of periconceptional vitamins or supplements that contain folic acid and diabetes mellitus-associated birth defects.
      highlights ongoing research.

      Vitamin D

      The function of vitamin D during pregnancy for both mother and fetus is not fully defined at present.
      • Hollis B.W.
      • Johnson D.
      • Hulsey T.C.
      • Ebeling M.
      • Wagner C.L.
      Vitamin D supplementation during pregnancy: Double-blind, randomized clinical trial of safety and effectiveness.
      Although vitamin D supplementation during pregnancy has been suggested as an intervention to protect against adverse gestational outcomes, including LBW,
      • Thorne-Lyman A.
      • Fawzi W.W.
      Vitamin D during pregnancy and maternal, neonatal and infant health outcomes: A systematic review and meta-analysis.
      the need, safety, and effectiveness of vitamin D supplementation during pregnancy remains controversial.
      • Hollis B.W.
      • Johnson D.
      • Hulsey T.C.
      • Ebeling M.
      • Wagner C.L.
      Vitamin D supplementation during pregnancy: Double-blind, randomized clinical trial of safety and effectiveness.
      The IOM recommends 600 IU per day of vitamin D to meet the needs of most North American adults, including pregnant women.

      Institute of Medicine. Dietary Reference Intakes for calcium and vitamin D. 2010. http://www.iom.edu/Reports/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D.aspx. Published November 30, 2010. Accessed September 4, 2012.

      Ongoing research suggests higher levels of supplementation are safe and effective for improving maternal and infant vitamin D status.
      • Hollis B.W.
      • Johnson D.
      • Hulsey T.C.
      • Ebeling M.
      • Wagner C.L.
      Vitamin D supplementation during pregnancy: Double-blind, randomized clinical trial of safety and effectiveness.

      Choline

      Choline is an essential nutrient during pregnancy because of its high rate of transport from mother to fetus. Maternal deficiency of choline can interfere with normal fetal brain development. Although choline is found in many foods, the majority of pregnant women are not achieving the Adequate Intake for pregnancy of 450 mg choline per day.
      • Caudill M.A.
      Pre- and postnatal health: Evidence of increased choline needs.

      Calcium

      The Dietary Reference Intake for calcium in pregnancy is equal to that of nonpregnant women of the same age because of increased efficiency in calcium absorption during pregnancy and maternal bone calcium mobilization.

      Institute of Medicine. Dietary Reference Intakes for calcium and vitamin D. 2010. http://www.iom.edu/Reports/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D.aspx. Published November 30, 2010. Accessed September 4, 2012.

      Women with suboptimal intakes (<500 mg/day) may need additional amounts to meet both maternal and fetal bone requirements.
      • Hacker A.N.
      • Fung E.B.
      • King J.C.
      Role of calcium during pregnancy: Maternal and fetal needs.

      Iodine

      Iodine is required for normal brain development and growth; iodine deficiency worldwide is a growing concern. During pregnancy, iodine requirements increase, making mother and developing fetus vulnerable. Congenital hypothyroidism is associated with cretinism, and clinical hypothyroidism has been associated with increased risk of poor perinatal outcomes, including prematurity, LBW, miscarriage, preeclampsia, fetal death, and impaired fetal neurocognitive development.
      • Obican S.G.
      • Jahnke G.D.
      • Soldin O.P.
      • Scialli A.R.
      Teratology public affairs committee position paper: Iodine deficiency in pregnancy.
      Recent national surveys indicate a subset of pregnant and lactating US women may have mild to moderately inadequate dietary iodine intake.
      • Stagnaro-Green A.
      • Abalovich M.
      • Alexander E.
      • et al.
      Guidelines of the American Thyroid Association for the diagnosis and management of thyroid disease during pregnancy and postpartum.
      The IOM recommends an iodine intake from dietary and supplement sources of 150 μg/day before conception, and 220 μg per day for pregnant women.
      • Swanson C.
      • Zimmermann M.
      • Skeaff S.
      • et al.
      Summary of an NIH workshop to identify research needs to improve the monitoring of iodine status in the United States and to inform the DRI.

      Environmental and Dietary Issues

      Foodborne Illness during Pregnancy

      Pregnant women and their fetuses are at increased risk of developing foodborne illness because of the hormonal changes of pregnancy that lead to decreased cell-mediated immune function. Of greatest concern during pregnancy are Listeria monocytogenes, Toxoplasma gondii, Brucella species, Salmonella species, and Campylobacter jejuni.

      Dean J, Kendall P. Food safety during pregnancy. 2012;9.372. Colorado State University Extension. Food and Nutrition Series. http://www.ext.colostate.edu/pubs/foodnut/09372.pdf. Accessed December 5, 2012.

      Pregnant women should closely adhere to food-safety recommendations outlined in the 2010 Dietary Guidelines for Americans.
      US Department of Agriculture
      US Department of Health and Human Services. Dietary Guidelines for Americans, 2010.
      Updated food-safety guidelines can be reviewed on the Food and Drug Administration at www.fda.gov/Food/ResourcesForYou/HealthEducators/ucm083308.htm.

      Benefits and Concerns Regarding Fish and Seafood Consumption

      The nutritional value of seafood is particularly important during fetal growth and development, as well as in early infancy and childhood.
      • McMillen I.C.
      • MacLaughlin S.M.
      • Muhlhausler B.S.
      • Gentili S.
      • Duffield J.L.
      • Morrison J.L.
      Developmental origins of adult health and disease: The role of periconceptional and foetal nutrition.
      Intake of n-3 fatty acids, particularly docosahexaenoic acid, from at least 8 oz of seafood per week for pregnant women is associated with improved infant visual and cognitive development.
      • McMillen I.C.
      • MacLaughlin S.M.
      • Muhlhausler B.S.
      • Gentili S.
      • Duffield J.L.
      • Morrison J.L.
      Developmental origins of adult health and disease: The role of periconceptional and foetal nutrition.
      Although prenatal mercury exposure (≥1 μg/g) was found to be associated with a greater risk of attention-deficit hyperactivity disorder−related behaviors, prenatal fish consumption of more than two servings per week was protective of those behaviors.
      • Sagiv S.K.
      • Thurston S.W.
      • Bellinger D.C.
      • Amarasiriwardena C.
      • Korrick S.A.
      Prenatal exposure to mercury and fish consumption during pregnancy and attention-deficit/hyperactivity disorder-related behavior in children.
      RDNs and dietetic technicians, registered, can help pregnant women balance the benefits of eating fish while avoiding high-mercury content seafood.

      Non-Nutritive Sweeteners

      Although calorie and blood glucose control are acknowledged benefits of non-nutritive sweeteners, limited research addresses the safety of non-nutritive sweeteners on healthy pregnancy or in GDM.

      Academy of Nutrition and Dietetics Evidence Analysis Library. Pregnancy and nutrition—Non-nutritive sweeteners. http://andevidencelibrary.com/evidence.cfm?evidence_summary_id=250587. Accessed December 3, 2013.

      Alcohol

      Alcohol should not be consumed by pregnant women or those who may become pregnant.
      • McMillen I.C.
      • MacLaughlin S.M.
      • Muhlhausler B.S.
      • Gentili S.
      • Duffield J.L.
      • Morrison J.L.
      Developmental origins of adult health and disease: The role of periconceptional and foetal nutrition.
      Drinking alcohol during pregnancy, especially in early pregnancy, may result in behavioral or neurological defects in the offspring and affect a child's future intelligence. No safe level of alcohol consumption during pregnancy has been established.
      • McMillen I.C.
      • MacLaughlin S.M.
      • Muhlhausler B.S.
      • Gentili S.
      • Duffield J.L.
      • Morrison J.L.
      Developmental origins of adult health and disease: The role of periconceptional and foetal nutrition.

      Caffeine

      Caffeine half-life increases in pregnancy from 3 hours in the first trimester to 80 to 100 hours in late pregnancy. Women who are pregnant or trying to become pregnant are advised by the American College of Obstetricians and Gynecologists
      American College of Obstetrics and Gynecology
      ACOG Committee opinion no. 462: Moderate caffeine consumption during pregnancy.
      to consume no more than 200 mg of caffeine per day—the approximate amount in one 12-oz cup of coffee. However, birth defects research indicates moderate or high amounts of beverages and foods containing caffeine do not increase the risk of congenital malformations, miscarriage, preterm birth, or growth retardation.
      • Brent R.L.
      • Christian M.S.
      • Diener R.M.
      Evaluation of the reproductive and developmental risks of caffeine.

      Hydration and Water Needs

      Adequate hydration is essential to healthy pregnancy, as a woman accumulates 6 to 9 L of water during gestation. The total water Adequate Intake for pregnancy (including drinking water, beverages and food) is 3 L/day. This includes approximately 2.3 L (approximately 10 cups) as total beverages.

      Institute of Medicine. Dietary reference intakes for water, potassium, sodium, chloride, and sulfate. http://www.nap.edu/openbook.php?record_id=10925&page=151. Published 2005. Accessed October 21, 2012.

      Energy Drinks

      An energy drink is any beverage that contains some form of legal stimulant and/or vitamins added to provide a short-term boost in energy. These drinks may contain substantial and varying amounts of sugar and caffeine, as well as taurine, carnitine, inositol, ginkgo, and milk thistle. Many of these have not been studied for safety during pregnancy. Ginseng, another common ingredient, is not recommended for use during pregnancy. The avoidance of energy drinks during pregnancy is advised.

      Sugar-Sweetened Drinks

      Sugar-sweetened beverages, including regular sodas, sport drinks, energy drinks, and fruit drinks, provide 35.7% of added sugars in the US diet.
      • McMillen I.C.
      • MacLaughlin S.M.
      • Muhlhausler B.S.
      • Gentili S.
      • Duffield J.L.
      • Morrison J.L.
      Developmental origins of adult health and disease: The role of periconceptional and foetal nutrition.
      Reduced consumption of sources of added sugars lowers the calorie content of the diet without compromising nutrient adequacy.

      Health Conditions Between and After Pregnancies

      Maternal return to healthy weight status postpartum can prevent future overweight and obesity.
      • McMillen I.C.
      • MacLaughlin S.M.
      • Muhlhausler B.S.
      • Gentili S.
      • Duffield J.L.
      • Morrison J.L.
      Developmental origins of adult health and disease: The role of periconceptional and foetal nutrition.
      The 2010 Dietary Guidelines for Americans forms the basis for nutrition counseling for postpartum women, and RDNs and dietetic technicians, registered, can assist women in achieving their prepregnancy weight.
      US Department of Agriculture
      US Department of Health and Human Services. Dietary Guidelines for Americans, 2010.
      Outside of weight status, recent research has shown that diet quality, dietary intake, and overall nutritional status can affect the risk of postpartum depression. An association among n-3 fatty acids, serotonin transporter genotype, and postpartum depression has been identified.
      • Shapiro G.D.
      • Fraser W.D.
      • Séguin J.R.
      Emerging risk factors for postpartum depression: Serotonin transporter genotype and omega-3 fatty acid status.
      Low-income women with depressive symptoms and life stressors are at risk for low-prenatal diet quality, so intensive dietary intervention before and during pregnancy may be needed to promote optimal health.
      • Fowles E.R.
      • Stang J.
      • Bryant M.
      • Kim S.H.
      Stress, depression, social support, and eating habits reduce diet quality in the first trimester in low-income women: A pilot study.
      The risk of maternal and infant mortality and pregnancy-related complications can be reduced with increased access to quality interconception care.

      Conclusions

      Pregnancy has been regarded as a maternal phase with requisite additional nutritional requirements; mounting evidence suggests that the prenatal period constitutes a critical convergence of short- and long-term factors affecting the lifelong health of mother and child. The aim of prenatal nutrition is to support a healthy uterine environment for optimal fetal development while supporting maternal health.
      • Shapira N.
      Prenatal nutrition: A critical window of opportunity for mother and child.
      The ideal prenatal diet should limit overconsumption for the mother and prevent undernutrition for the fetus
      • Shapira N.
      Prenatal nutrition: A critical window of opportunity for mother and child.
      ; a healthy lifestyle includes regular physical activity and avoidance of harmful practices.

      References

      1. Academy of Nutrition and Dietetics. Practice Paper of the Academy of Nutrition and Dietetics: Nutrition and lifestyle for a healthy pregnancy outcome. http://www.eatright.org/members/practicepapers/. Published July 1, 2014. Accessed May 22, 2014.

      2. Centers for Disease Control and Prevention. Division of Birth Defects and Developmental Disabilities. Birth defects. http://www.cdc.gov/ncbddd/birthdefects/index.html. Accessed October 4, 2012.

      3. Centers for Disease Control and Prevention. FastStats: Births and natality. http://www.cdc.gov/nchs/fastats/births.htm. Accessed October 4, 2012.

      4. Rasmussen K.M. Yaktine A.L. Weight Gain During Pregnancy: Reexamining the Guidelines. National Academies Press, Washington, DC2009 (Accessed March 19, 2014)
        • Shapira N.
        Prenatal nutrition: A critical window of opportunity for mother and child.
        Womens Health. 2008; 4: 639-656
        • Vesco K.K.
        • Dietz P.M.
        • Rizzo J.
        • et al.
        Excessive gestational weight gain and postpartum weight retention among obese women.
        Obstet Gynecol. 2009; 114: 1069-1075
        • Academy of Nutrition and Dietetics
        Position of the Academy of Nutrition and Dietetics and American Society for Nutrition: Obesity, reproduction, and pregnancy outcomes.
        J Am Diet Assoc. 2009; 109: 918-927
      5. Centers for Disease Control and Prevention. 2011 National Diabetes fact sheet: Gestational diabetes in the United States. http://www.cdc.gov/diabetes/pubs/estimates11.htm. Accessed November 11, 2012.

      6. Academy of Nutrition and Dietetics Evidence Analysis Library. Gestational diabetes evidence-based nutrition practice guideline. http://andevidencelibrary.com/topic.cfm?cat=3733. Accessed December 6, 2013.

        • Seely E.W.
        • Ecker J.
        Chronic hypertension in pregnancy.
        N Engl J Med. 2011; 365: 439-446
        • Tobias D.K.
        • Zhang C.
        • Chavarro J.
        • et al.
        Prepregnancy adherence to dietary patterns and lower risk of gestational diabetes.
        Am J Clin Nutr. 2012; 96: 289-295
        • Krakowiak P.
        • Walker C.K.
        • Bremer A.A.
        • et al.
        Maternal metabolic conditions and risk for autism and other neurodevelopmental disorders.
        Pediatrics. 2012; 129: e1121-e1128
        • Hanley B.
        • Dijane J.
        • Fewtrell M.
        • et al.
        Metabolic imprinting, programming and epigenetics—A review of present priorities and future opportunities.
        Br J Nutr. 2010; 104: S1-S25
        • McMillen I.C.
        • MacLaughlin S.M.
        • Muhlhausler B.S.
        • Gentili S.
        • Duffield J.L.
        • Morrison J.L.
        Developmental origins of adult health and disease: The role of periconceptional and foetal nutrition.
        Basic Clin Pharmacol Toxicol. 2008; 102: 82-89
        • US Department of Health and Human Services
        Physical activity for women during pregnancy and the postpartum period.
        2008 Physical Activity Guidelines for Americans. Office of Disease Prevention & Health Promotion, Washington, DC2008: 41-42 (Accessed September 25, 2012)
        • Deierlein A.L.
        • Siega-Riz A.M.
        • Evenson K.R.
        Physical activity during pregnancy and risk of hyperglycemia.
        J Womens Health. 2012; 21: 769-775
        • Ruchat S.M.
        • Davenport M.H.
        • Giroux I.
        • et al.
        Nutrition and exercise reduce excessive weight gain in normal-weight pregnant women.
        Med Sci Sports Exerc. 2012; 44: 1419-1426
        • Gautam C.S.
        • Saha L.
        • Sekhri K.
        • Saha P.K.
        Iron deficiency in pregnancy and the rationality of iron supplements prescribed during pregnancy.
        Medscape J Med. 2008; 10 (Accessed October 3, 2012): 283-288
        • Khalafallah A.A.
        • Dennis A.E.
        Iron deficiency anaemia in pregnancy and postpartum: Pathophysiology and effect of oral versus intravenous iron therapy.
        J Pregnancy. 2012; 2012 ([published online June 26, 2012].) (630519)https://doi.org/10.1155/2012/630519
        • US Department of Agriculture, US Department of Health and Human Services
        2010 US Dietary Guidelines Advisory Committee. Part D. Section 2: Nutrient adequacy.
        in: Report of the Dietary Guidelines Advisory Committee on the Dietary Guidelines for Americans, 2010. 7th ed. US Government Printing Office, Washington, DC2010 (D2-38)
        • US Department of Agriculture
        US Department of Health and Human Services. Dietary Guidelines for Americans, 2010.
        7th ed. US Government Printing Office, Washington, DC2010
      7. Centers for Disease Control and Prevention. Folic acid: Recommendations. http://www.cdc.gov/ncbddd/folicacid/recommendations.html. Accessed September 24, 2012.

        • Correa A.
        • Gilboa S.M.
        • Botto L.D.
        • et al.
        Lack of periconceptional vitamins or supplements that contain folic acid and diabetes mellitus-associated birth defects.
        Am J Obstet Gynecol. 2012; 206 (e1-e13): 218
        • Hollis B.W.
        • Johnson D.
        • Hulsey T.C.
        • Ebeling M.
        • Wagner C.L.
        Vitamin D supplementation during pregnancy: Double-blind, randomized clinical trial of safety and effectiveness.
        J Bone Miner Res. 2011; 26: 2341-2357
        • Thorne-Lyman A.
        • Fawzi W.W.
        Vitamin D during pregnancy and maternal, neonatal and infant health outcomes: A systematic review and meta-analysis.
        Paediatr Perinat Epidemiol. 2012; 26: 75-90
      8. Institute of Medicine. Dietary Reference Intakes for calcium and vitamin D. 2010. http://www.iom.edu/Reports/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D.aspx. Published November 30, 2010. Accessed September 4, 2012.

        • Caudill M.A.
        Pre- and postnatal health: Evidence of increased choline needs.
        J Am Diet Assoc. 2010; 110: 1198-1206
        • Hacker A.N.
        • Fung E.B.
        • King J.C.
        Role of calcium during pregnancy: Maternal and fetal needs.
        Nutr Rev. 2012; 70: 397-409
        • Obican S.G.
        • Jahnke G.D.
        • Soldin O.P.
        • Scialli A.R.
        Teratology public affairs committee position paper: Iodine deficiency in pregnancy.
        Birth Defects Res. 2012; 94: 677-682
        • Stagnaro-Green A.
        • Abalovich M.
        • Alexander E.
        • et al.
        Guidelines of the American Thyroid Association for the diagnosis and management of thyroid disease during pregnancy and postpartum.
        Thyroid. 2011; 21: 1081-1125
        • Swanson C.
        • Zimmermann M.
        • Skeaff S.
        • et al.
        Summary of an NIH workshop to identify research needs to improve the monitoring of iodine status in the United States and to inform the DRI.
        J Nutr. 2012; 142: 1175S-1185S
      9. Dean J, Kendall P. Food safety during pregnancy. 2012;9.372. Colorado State University Extension. Food and Nutrition Series. http://www.ext.colostate.edu/pubs/foodnut/09372.pdf. Accessed December 5, 2012.

        • Sagiv S.K.
        • Thurston S.W.
        • Bellinger D.C.
        • Amarasiriwardena C.
        • Korrick S.A.
        Prenatal exposure to mercury and fish consumption during pregnancy and attention-deficit/hyperactivity disorder-related behavior in children.
        Arch Pediatr Adolesc Med. 2012; 166: 1123-1131
      10. Academy of Nutrition and Dietetics Evidence Analysis Library. Pregnancy and nutrition—Non-nutritive sweeteners. http://andevidencelibrary.com/evidence.cfm?evidence_summary_id=250587. Accessed December 3, 2013.

        • American College of Obstetrics and Gynecology
        ACOG Committee opinion no. 462: Moderate caffeine consumption during pregnancy.
        Obstet Gynecol. 2010; 116: 467-468
        • Brent R.L.
        • Christian M.S.
        • Diener R.M.
        Evaluation of the reproductive and developmental risks of caffeine.
        Birth Defects Res (Part B). 2011; 92: 152-187
      11. Institute of Medicine. Dietary reference intakes for water, potassium, sodium, chloride, and sulfate. http://www.nap.edu/openbook.php?record_id=10925&page=151. Published 2005. Accessed October 21, 2012.

        • Shapiro G.D.
        • Fraser W.D.
        • Séguin J.R.
        Emerging risk factors for postpartum depression: Serotonin transporter genotype and omega-3 fatty acid status.
        Can J Psychiatry. 2012; 57: 704-712
        • Fowles E.R.
        • Stang J.
        • Bryant M.
        • Kim S.H.
        Stress, depression, social support, and eating habits reduce diet quality in the first trimester in low-income women: A pilot study.
        J Acad Nutr Diet. 2012; 112: 1619-1625