Nutrition%20in%20pregnancy Treatment
Pharmacotherapy
- Nutrient requirements during pregnancy are increased in order to support fetal growth; thus, inadequate nutrients at this time may affect fetal tissue development predisposing the infant to chronic conditions in later life such as bone health, cardiovascular disease, cognition, immune function, obesity and diabetes
- In the 1st trimester of pregnancy, requirement for folic acid, vitamin A, iodine, vitamin B12, and polyunsaturated fatty acids (PUFAs) is increased while in the 2nd and 3rd trimesters, demand for energy and protein, folic acid, vitamin A, iodine, iron, calcium, omega-3 fatty acids, zinc, copper, B vitamins, and vitamin D is increased
- Pregnant women who do not consume an adequate or balanced diet may be given multiple micronutrient (vitamins and minerals) supplementation (MMS)
- WHO recommends antenatal MMS which contain iron and folic acid
Macronutrients
Carbohydrates
- Serve as fuel for growth
- Low-glycemic index carbohydrates are preferred
- During pregnancy, diets with low glycemic index are associated with improved glucose tolerance and less excessive gestational weight gain
- Sources of low-glycemic index carbohydrates include whole grains, unprocessed rice, nontuberous vegetables, most fruits, dairy products, beans, nuts
Fats (Omega-3 Fatty Acids)
- Preferred sources of fat are the PUFAs
- Omega-3 fatty acids come from ALA, a type of PUFA
- Improved infant cognitive and visual development is associated with intake of omega-3 fatty acids including DHA and EPA (eicosapentaenoic acid)
- Risk of early preterm birth (<34 weeks of gestation) is decreased with regularly eating fish and supplementing with omega-3 long-chain PUFA
- Sources of omega-3 fatty acids include salmon, sardines, eel, jade perch, yellow croaker
- Omega-3 DHA supplementation with at least an average of 300 mg daily should be achieved in women who do not regularly eat fish
- Vegetarians may consume ALA-rich foods such as canola oil, olive oil, walnuts and flaxseeds
- Avoid high-mercury content seafood as prenatal mercury exposure may damage the developing brain of the fetus, as well as milder motor, psychosocial and intellectual impairment
- Fish with high levels of mercury include shark, marlin, swordfish, king mackerel, tuna, orange roughy, bigeye, etc
Proteins
- The building blocks of cellular structural and functional components
- It is advised that undernourished pregnant women take a balanced protein dietary supplementation (not too low or excessive) to decrease the risk of stillbirths, or low-birthweight or small-for-gestational-age newborns
- Sources of protein are meat, fish, poultry, eggs, dairy products, legumes, grains, nuts
Micronutrients
Calcium
- Essential for the development of bones and teeth
- Pregnancy requirements for calcium are similar to that in nonpregnant women due to increased efficiency in absorption of calcium and mobilization of maternal bone calcium
- 1.5-2.0 g oral elemental calcium supplementation daily is recommended for pregnant women with low dietary calcium intake for reduction of risk of pre-eclampsia
- The risk of gestational hypertension and preterm labor is increased with inadequate intake of calcium while pregnant
- Increased dose of calcium intake leads to its decreased absorption, thus multiple small doses of calcium should be taken within the day, eg 3 divided doses taken if possible at mealtimes
- Various calcium compounds contained in calcium supplements have different amounts of elemental calcium
- 1 g of elemental calcium equals 4 g of calcium acetate, 2.5 g of calcium carbonate, 5 g of calcium citrate, 11 g of calcium gluconate and 8 g of calcium lactate
- Sources of calcium include milk, cheese, yoghurt, soy, tofu, dark green vegetables, fruits, nuts, beans, sesame seeds, dried fish or shrimps, sardines
Folic acid (Folate)
- Folic acid supplementation prevents neural tube defects in the fetus
- Other folic acid-sensitive congenital anomalies include oral facial clefts, congenital defects in the heart and urinary tract and limb-reduction anomalies
- It is recommended to take folic acid pre-pregnancy for 2-3 months and to continue supplementation throughout pregnancy until 3 months postpartum or completion of breastfeeding
- May be given daily as an oral multivitamin supplement which also contains vitamin B12 2.6 mcg and iron 16-20 mg
- Sources of folic acid include dark green leafy vegetables, cabbage, tomatoes, nuts, beans, legumes, whole grain products, liver, fruits eg orange or cantaloupe
Iodine
- Required for fetal brain development and growth
- Iodine deficiency can cause maternal and fetal hypothyroidism while excessive intake can cause fetal goiter
- Sources of iodine include fish, seafood eg mussels, oysters, and prawns, seaweeds, egg yolk, milk and milk products
- Iodized salt may be used for cooking, however, try to limit salt use
Iron
- For fetal brain development and growth and prevention of anemia during pregnancy
- Risk for low birth weight and preterm birth as well as maternal anemia and puerperal sepsis can be prevented with 30-60 mg daily oral iron supplementation in pregnant women
- Increased dose of iron intake leads to its decreased absorption, thus high amounts of supplementation are divided into several doses within the day
- 30 mg of elemental iron equals 90 mg of ferrous fumarate, 150 mg of ferrous sulfate heptahydrate or 250 mg of ferrous gluconate
- May also consider alternate-day dosing of oral iron supplements (twice the daily target dose) in iron-deficient anemic women to increase total iron absorption and decrease gastrointestinal symptoms
- If daily oral iron intake is not tolerated due to side effects, intermittent supplementation with oral iron (120 mg elemental iron) and folic acid (2800 mcg) once weekly is advised
- Consider giving parenteral iron in women who are unresponsive or intolerant of oral iron from the 2nd trimester onward and during postpartum
- Once hemoglobin level becomes normal, patient may be switched to the standard prenatal dose for prevention of anemia recurrence
- Sources of iron include beef, fish, pork, poultry, eggs, liver, dark green leafy vegetables, dried beans, nuts
- Limit consumption of liver, particularly in early pregnancy, as liver contains a high concentration of preformed vitamin A and excessive vitamin A (>3000 mcg retinol equivalents/day) is teratogenic
- Iron-rich foods are usually also rich in zinc and zinc is essential for fetal growth, immune function and neurological development
Vitamin A
- Important for vision, immune function and growth
- Supplementation for pregnant women is only advised in areas where vitamin A deficiency is considered to be a severe public health issue
- Excessive supplementation with vitamin A can cause liver dysfunction and birth defects, ie abnormal development of the heart, lungs, eyes and skull
- Sources of vitamin A include darkly colored fruits and vegetables, oily fruits, red palm oil
Vitamin B12
- For neural tube formation and brain development
- Sources of vitamin B12 include eggs, milk or cereals fortified with vitamin B12
- Other B vitamins (vitamin B1 [thiamine], vitamin B2 [riboflavin], vitamin B3 [niacin], vitamin B6 [pyridoxine], biotin, pantothenate) are also important for fetal growth and brain development
- Sources include meat, fish, poultry, eggs, starchy vegetables, legumes, fruits, nuts
Vitamin C
- Aids the body in absorbing iron from food
- Sources of vitamin C include vegetables and fruits
- When consuming iron-containing foods, iron absorption is enhanced when the following vitamin C-rich foods are also taken: Cantaloupe, grapefruit, kiwi, orange, strawberry, broccoli, bell pepper, tomato
Vitamin D
- Important for fetal bone development and aids in the absorption of calcium and phosphate
- Most vitamin D is formed endogenously in the skin when exposed to sunlight which is its most important source
- Sunlight exposure for 5-15 minutes 2-3x/week during summer may be done but a longer sun exposure may be needed during winter, for dark-skinned individuals, for those whose skin is covered extensively with clothing, or with sunscreen use
- Sources of vitamin D include eggs, liver, milk and milk products fortified with vitamin D, fatty fish eg sardines, salmon
Daily Recommended Dietary Allowances of Micronutrients for Pre-pregnant, Pregnant and Lactating Women | |||
---|---|---|---|
Micronutrient |
Pre-pregnant |
Pregnant |
Lactating |
Calcium | 700-1000 mg | 1000 mg | 1000 mg |
Folic acid | 400 mcg | 600 mcg | 500 mcg |
Iodine | 150 mcg | 200 mcg | 200 mcg |
Iron | 29-39 mg | * | 15-20 mg |
Vitamin A | 1.1 mg | 800 mcg | 850 mcg |
Vitamin B1 | 1.1 mg | 1.4 mg | 1.5 mg |
Vitamin B2 | 1.1 mg | 1.4 mg | 1.6 mg |
Vitamin B3 | 14 mg | 18 mg | 17 mg |
Vitamin B6 | 1.3 mg | 1.9 mg | 2.0 mg |
Vitamin B12 | 2.4 mcg | 2.6 mcg | 2.8 mcg |
Vitamin C | 70 mg | 80 mg | 95 mg |
Vitamin D | 5-10 mcg | 5 mcg | 5 mcg |
Zinc | 4.4 mg | 5-10 mg | 7.2-9.5 mg |
WHO recommends a daily oral supplementation of 30-60 mg of elemental iron for pregnant women.
List shown above is not exhaustive and as recommendations may vary between countries, please refer to available nutrition guidelines from local health authority.
References: Barba CV, Cabrera MI. Recommended dietary allowances harmonization in Southeast Asia. Asia Pac J Clin Nutr. 2008;17 Suppl 2:405-408. Food and Nutrition Board, Institute of Medicine, National Academies. Dietary reference intakes (DRIs): Recommended dietary allowances and adequate intakes, vitamins. National Institutes of Health. https://www.ncbi.nlm.nih.gov/.