* * Nutrition in Pregnancy and Lactation. Maternal weight gain & nutritional status

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1 Nutrition in Pregnancy and Lactation Nutritional recommendations for the health of» mother and fetus» mother and infant. Transfer across the placenta: from maternal to fetal circulation Nutrients: necessary for normal dev. Other beneficial factors: e.g., Ig s Toxic substances: may interfere with normal dev., e.g., drugs and alcohol, infectious agents, Hg and other metals, industrial chemicals & other pollutants * * * Disruption due to nutrient deficiency, excess toxin, or other insult Maternal weight gain & nutritional status Nutritional status of woman influences fertility of woman survival and development of baby baby s epigenetic programs with potential relation to later disease risk Maternal weight gain includes increases in mass of maternal tissues, placenta, fetus necessary part of pregnancy recommended weight gain depends on mother s BMI (inverse relation) a typical, recommended weight gain for normal BMI, single pregnancy, is about kg (higher for teen preg. & multiple births) Obesity-related problems Pregnancy in adolescence - increased risk of LBW infant ( mortality, neurodev. problems) - most common deficiencies: iron, calcium, folate - recommended intake in teen preg vs. older preg: Mg, Ca*, P*, (Zn) *same as for non-pregnant teen 1

2 Nutritional requirements during pregnancy Some common general recommendations: Sufficient energy and protein Sufficient micronutrients supplements or folate/iron may be needed Avoid alcohol, high caffeine.also emphasis on avoiding environmental toxins and some medications Normal sodium (iodized salt) intake avoid both excess and restriction Energy increased energy about 15% higher in 2 nd trimester and 20% in 3 rd trimester supports fetal/placental growth supports increased nutrient transport/metabolism in mother meets physical activity* needs often energy and protein deficiency occur together Protein increased protein about 50% higher, especially in 2 nd half of pregnancy (100% if twins) supports synthesis of maternal and fetal tissues too much may lead to increased calcium loss Folate increased folate increase of 50% supports increased cell division in maternal & fetal tissues recommended intake is difficult to reach through normal food sources.supplements or fortified foods often needed food sources: green leafy veg., legumes, orange juice, nuts...liver is not a recommended food during pregnancy FOOD (1 typical serving) liver 200 pinto beans/lentils/chickpeas 150 spinach 120 orange juice 70 avocado 100 pasta (fortified) 100+ bread slices (fortified) 50+ Folate (approximate mg) Folic acid 2

3 severe folate deficiency results in megaloblastic anemia (a type of macrocytic anemia) mild deficiencies (common) may also be problematic premature and LBW infants neural tube defects (by day 28).up to half may be prevented by folate supplements in early pregnancy other birth defects (animal studies) some drugs can lower folate status upper limit about micrograms Vitamin A requirements and its potential toxicity recommended intake is about same for non-preg. woman excess retinoids (not carotenoids): teratogenic avoid high-retinol supplements / frequent consumption of foods such as liver vitamin A deficiency (animal studies): teratogenic isotretinoin (anti-acne medicine): teratogenic defects: craniofacial, eye, limb, cardiac, CNS RAE, retinol acitivity equivalent 1 RAE = 1 mcg retinol = 3.3 IU (int. units) = 12 mcg beta-carotene Norm. Defic. Vitamin B6 increased intake increase of about 50% supports increased protein synthesis increases niacin synthesis from tryptophan Niacin,Thiamin, Riboflavin, increases of about 30% Calcium recommended intake is about same as for non-preg. State (normal intakes and recommendations can differ among the countries ) maternal calcium fetal skeleton pregnancy hormones increase absorption from dietary sources 3

4 Iron increased iron about 50% increase supports increased demand during last half of pregnancy (maternal red blood cells, fetus, placenta ) supplements or fortified foods often required to reach recommended intake levels prevents anemia (microcytic anemia) FOOD (1 typical serving) Iron (approximate mg) Shellfish (food safety issues..) 3 steak (beef) 2 chicken, pork, fish, shrimp 1 Legumes * 2+ fortified breakfast cereals * 3 peanuts, other nuts/seeds * 1+ fortified bread/pasta * 1+ *non-heme Zinc increased zinc increase of about 40% required for many metabolic reactions in body prevention of developmental defects (animal exp.) absorption can be competed by iron/calcium... Iodine increased iodine increase of about 50% prevention of neuro-developmental deficiencies & mental retardation Magnesium increased magnesium increase of about 10-15% maternal levels decrease during pregnancy & lactation prevention of leg cramps, pre-eclampsia??... pregnancy-induced hypertension PIH gestational hypertension pre-eclamptic toxemia PET - high blood pressure - high urinary protein - edema - low uterine blood flow - placental size - intrauterine growth restriction (IUGR) ~6% of pregnancies; often 3 rd trimester..causes? has been associated with low vit. D & Mg, older age, placental vascular injury, overweight eclampsia - severe progression of PET (progression may be by extra Mg) - seizures - dizziness - disturbed eyesight - can be fatal to both mother and fetus - medical response: C-section 4

5 Other pregnancy-associated problems Nausea and vomiting Affects majority of pregnant women; ~1% severe symptoms (HG) HG: dehydration, weight loss, electrolyte imbalances may require parenteral intervention/hospitalization Some recommendations: small meals/snacks frequently, choose appealing foods Constipation and hemorrhoids Increased fluid and fibre-rich foods Laxatives are usually not recommended in pregnancy Gastric reflux (heartburn) Affects about half of pregnant women (mostly due to hormonal changes and physical enlargement of uterus) Antacids not typically recommended (unless prescribed by physician) Some recommendations: slow the eating process, eat smaller meals, avoid large volume of fluids during meals, avoid spicy foods, avoid lying down after meals Foods and non-nutritive substances during pregnancy Food groups Food recommendations typically follow from nutrient recommendations Increased intake of milk products and other high protein foods Milk products: protein, calcium, calories, vitamin D Intake of meats and other protein/iron-rich foods, also fish for protein/ omega-3 Avoid organ meats such as liver with high vitamin A (retinol) and possible accumulated toxins, also high mercury fish Increased intake of legumes, green-leafy vegetables and other folate richfoods Increased intake of foods with high nutrient density for other micronutrients 5

6 Potentially toxic substances Alcohol (Ethanol) Possible effects: spontaneous abortion; growth failure; craniofacial & joint abnormalities teratogen Fetal Alcohol Syndrome (FAS) & Fetal Alcohol Effects (FAE) research ongoing into toxicity mechanisms amounts and frequencies of alcohol intake that lead to FAE and FAS are not precisely known.avoid all alcohol Artificial sweeteners aspartame: phenylalanine (potential problem with PKU) saccharin: weak carcinogen in rats acesulfame K, sucralose: safe? long-term studies? Caffeine limited intake recommended, but insufficient data for exact limits (1-2 cups of coffee/equivalent) effects on fetus? High doses may be harmful especially early in preg. can increase calcium excretion, risk of dehydration Food toxins and contaminants Pesticides Mercury Lead Bisphenol A Listeria bacteria other Lactation Some benefits for infant: Nutritional balanced -In terms of macronutrients, prevents overfeeding Anti-infection factors (Ig s) Non-allergenic May lower risk of diabetes, asthma, some leukemias For mother, may lower risk of breast cancer May be contraindicated for women with some types of infections, drug abuse, or those requiring some medications (e.g., cancer chemotherapeutics) Milk composition the levels of some milk components depend, at least partly, on mother s diet, e.g., trace minerals (Se, Zn); some vitamins (B6, D*); DHA and EPA; trans fats; some toxins.*also sunlight exposure 6

7 ENERGY increase of about kcal (1-12 months of breastfeeding) 300 kcal of milk (~400 ml) production requires ~350 kcal of energy expenditure by mother PROTEIN increase of about 50% MINERALS Zinc, increase of about 50% Iodine, increase of about 90% Iron, decrease of about 50% All changes on this page are relative to nonlactating, non-pregnant woman of same age VITAMINS Vitamin A, increase of about 90% Vitamin C, increase of about 80% Vitamin B6, increase of about 50% Niacin,Thiamin, Riboflavin, increases of about 20-40% B12 and folate, increases of about 20% Essential fatty acids in Pregnancy and Lactation -alpha-linolenic (ALL, an omega-3) and linoleic (LL, an omega-6) -made by plants/algae..enter food chain -increased intake, especially of omega-3, recommended -ALL can be elongated to EPA & DHA; LL to arachidonic acid & DPA -extent and efficiency of EPA and DHA formation in body can vary....direct dietary sources such as low-mercury fish are recommended (e.g., 2 serv/wk) -omega-3 s such as DHA are important for normal fetal & infant dev. 7