Nutritional counselling is the cornerstone of prenatal care for pregnant women. The nutritional status of a pregnant woman not only affect herself but also influences the health of the unborn baby. One needs to pay close attention to the nutritional value of food in the diet of pregnant women as her nutritional requirement is different from nonpregnant women and people. The nutritional requirement is influenced by race-ethnicity, age, body mass index, cultural food choice, socioeconomic status. In this article, you will learn about the maternal physiological adaptations as well as macro and micronutrient requirements of pregnant women during pregnancy.
Energy expenditure during pregnancy
From Garbh Sanskar the estimated calorie requirement for a pregnant lady to support the full course of pregnancy is 80,000 kcal. From this value, we can conclude that the caloric intake of pregnant women is increased by 300 kcal/day during pregnancy. The energy requirement for pregnant women first trimester is the same as for nonpregnant women. For the second trimester, the energy requirement is 340 kcal per day and for the third trimester, it is 452 kcal per day. The energy requirement may vary significantly depending upon the medical condition, BMI, age and physical activity level.
Physiological changes during pregnancy
Physiological changes during pregnancy alter normal ranges of several laboratory values of pregnant women. The volume of both RBC and plasma increases during pregnancy, but the rate of increase of plasma is higher than RBC, therefore, haemoglobin less than 10.5 g/dl considered anaemic during the second trimester. The total serum protein also decreases by approximately 30% compared to the value of nonpregnant women. The free levels of vitamin D, thyroid hormones, corticosteroids, and sex steroids decrease in pregnant women in comparison to nonpregnant women.
Nutrients
Macronutrients –
Protein- the protein intake of pregnant women is 60g/day, which is a 14 g/day more than a nonpregnant woman. In other words, this increase reflects a change of 1.1 g of protein /kg of body weight/ day from 0.8g of protein/kg/ day for nonpregnant women.
Carbohydrate – the carbohydrate should wave off 45-64% of the daily calorie requirement and pregnant women should take this carbohydrate in 6 to 9 servings of whole-grains daily.
Fat- the fat should contribute 20% to 35% of daily calories to pregnant women this data is similar to nonpregnant.
Micronutrient
Pregnant women required 200-800µg of folic acid daily to fulfil the physical requirements of the body. The folic acid synthetic form of naturally occurring B vitamin, and folate. The natural source of folate is a dark green leafy vegetable, nuts, and citrus food. Women with a history of a neural tube defect in a prior pregnancy should take a higher dose of 4mg of folic acid daily for the next pregnancy. The iron requirement for pregnant women is twice the amount of iron required by nonpregnant women. Garbh Sanskar standard prenatal iron requirement for pregnant woman is 27mg. vitamin C supplements help with iron absorption whereas tea and milk can inhibit iron absorption in the body. Vitamin D is manufactured by the skin when it exposes to the Sun. it is a fat-soluble vitamin and found in milk and juices. Vitamin D helps in calcium absorption. The deficiencies of vitamin D in pregnancy can high risk of rickets and fractures. The optimal level of vitamin D required in pregnancy has not been established yet. Vitamin A is essential for the proliferation and differentiation of cells and their development into the heart, spine, eyes, ears. The maximum supplement of vitamin A is 8000 IU/day. The excessive doses of vitamin A can cause cardiac and facial birth defects in the newborn baby.
Daily dietary allowance for pregnant women.
| Nutrient | Non-pregnant | Pregnant women |
| Vitamin A (µg/d) | 700 | 1300 |
| Vitamin D (µg/d) | 5 | 15 |
| Vitamin E (µg/d) | 15 | 15 |
| Vitamin K(µg/d) | 90 | 90 |
| Folate (µg/d) | 400 | 600 |
| Niacin mg/d | 14 | 18 |
| Riboflavin mg/d | 1.1 | 1.4 |
| Thiamin (mg/d) | 1.1 | 1.4 |
| Vitamin B6 (mg/d) | 1.3 | 1.9 |
| Vitamin B12 (µg/d) | 2.4 | 2.6 |
| Vitamin C (mg/d) | 2.4 | 2.6 |
| Calcium (mg/d) | 1,000 | 1,000 |
| Iron (mg/d) | 18 | 27 |
| Phosphorus (mg/d) | 700 | 700 |
| Selenium (µg/d) | 55 | 60 |
| Zinc (mg/d) | 8 | 11 |
Typical composition of micronutrient in a prenatal vitamin
| Component | Amount |
| Vitamin A | 4000 IU as beta carotene |
| Vitamin D3 | 400 IU as cholecalciferol |
| Vitamin E | 11 IU take it as dl- alpha tocopheryl acetate |
| Folic acid | 800µg |
| Niacin | 18 mg as niacinamide |
| Riboflavin | 1.7 mg as thiamin mononitrate |
| Thiamin | 1.5 mg |
| Vitamin B6 | 2.6 mg as pyridoxine hydrochloride |
| Vitamin B12 | 4µg as cyanocobalamin |
| Vitamin C | 100mg as ascorbic acid |
| Calcium | 150mg as calcium carbonate |
| Iron | 27 mg as ferrous fumarate |
| Zinc | 25mg as zinc oxide |
Table: Diagnostic testing along with prophylaxis and treatment of micro and macronutrient deficiencies in pregnancies after bariatric surgery.
| Component | Diagnostic testing(serum) | Prophylaxis | Treatment if deficient |
| Protein | Serum albumin and prealbumin | 60g protein/day | Protein supplements |
| Vitamin A | Vitamin A, if clinically indicated | 4000 IU/day in prenatal vitamin | Vitamin A not to exceed 8000 IU/day |
| Vitamin D | 25-hydroxy vitamin D, if clinically indicated | 400-800 IU/day in prenatal vitamin | Calcitriol (vitamin D)1000 IU/day |
| Vitamin K | Vitamin K1, if clinically indicated | Not routinely given | Vitamin K1 1 mg/day Consult with hematologist |
| Folic acid | Complete blood count, red blood cell folate | 600-800 μg/day in prenatal vitamin | Folic acid 1000μg/day |
| Vitamin B12 | Complete blood cell count, Vitamin B12 | 4 μg/day in prenatal vitamin | Oral vitamin B12 350μg/day orIntramuscular1000 μg/month Consult with hematologist |
| Calcium | Total and ionized calcium | 250 mg/day in prenatal vitamin | Calcium citrate 1000mg/day with Vitamin D |
| Iron | Complete blood count, iron, ferritin, total iron binding capacity | 30 mg/day in prenatal vitamin | Ferrous sulfate 325 mg twice-three times/day with vitamin C |