Nutritional requirements during pregnancy

Normal and Therapeutic Nutrition 3(2+1)
Lesson 10:Maternal Nutrition

Nutritional requirements during pregnancy

  1. Energy: Additional energy of 300k cal is required for the following:
    • Growth and physical activity of the foetus
    • Growth of plasma
    • Normal increase in maternal body size
    • Additional work involved in carrying the weight of foetus and extra maternal tissues
    • Slow and steady rise in BMR during pregnancy

    ICMR recommended energy requirement of pregnant woman is as follows:

    Sedentary worker ------- 1875+300 = 2175 k cal/ day
    Moderate worker ------- 2225+ 300 = 2525 k cal/ day
    Heavy worker -------- 2925+ 300 = 3225 k cal/ day

    Increase in calories for trimester wise is as follows:

    1st trimester ------ 10 k cal/ day
    2nd trimester ------- 90 k cal/ day
    3rd trimester ------- 200 kcal/ day

  2. Protein:
  3. Normal protein requirement of an adult woman is 50g/ day. ICMR recommended an additional 15g for pregnant woman. Additional protein is essential for:

    • Rapid growth of foetus
    • Enlargement of uterus, mammary glands and placenta
    • Increase in maternal circulating blood volume and subsequent demand of increased plasma and maintenance of colloidal osmotic pressure and circulation of tissue fluids
    • Formation of amniotic fluid
    • Transfer of amino acids from mother to foetus up to 20 weeks ( all amino acids must be provided to the foetus as it cannot oxidise amino acids as a source of energy).

    If protein requirements are not met during pregnancy:

    • There is increased risk of pregnancy
    • Foetus may grow at the expense of mother
    • Maximum growth of baby cannot be obtained
    • Number of cells in tissues particularly in brain may not be normal.

    Milk, meat, egg and cheese are complete proteins with high biological value. Additional protein may be obtained from legumes and whole grains, nuts and oil seeds.

  4. Fat : 30g/ day

  5. Calcium:
  6. ICMR recommended calcium requirement of adult woman is 400 mg/ day. Requirement increases during pregnancy to 1000mg/day.

    Increased intake of calcium is highly essential for:

    • Calcification of foetal bones and teeth
    • For protection of calcium depletion from mother to meet high demands during lactation

    A full term foetal body is made of 30g of calcium

    Mother’s diet should contain less of phytic acid, adequate amount of vitamin D and sufficient amount of calcium to prevent ‘Osteomalacia’ and muscular cramps. Mother should avoid repeated pregnancies.

    Adequate milk and other dairy products and green leafy vegetables should be consumed (supplements if necessary).

  7. Iron:
  8. Normal iron requirement of an adult woman is 30mg/day. ICMR recommendation for iron during pregnancy is 38 mg/ day.

    Increase of 8 mg iron / day can be attributed to the following:

    • Infants are generally born with haemoglobin levels of 18- 22g/100ml of blood. Iron stores in the liver of the infant lasts from 3 to 6 months. Iron is also required for the growth of foetus and placenta. To achieve these levels mother must transfer 240 mg of iron to the foetus during gestation.
    • Iron is also required for the formation of haemoglobin as there is 40 -50 per cent increase in maternal blood volume. For this 400mg of iron is required.
    • Loss of maternal iron through skin and sweat is about 170mg of iron.

    The total iron requirement for the entire period of pregnancy is 810mg. including blood loss at the time of delivery. Liver, dried beans, dried fruits, green leafy vegetables, eggs, enriched cereals and iron fortified salt provide additional sources of iron.

  9. Sodium:
  10. During pregnancy, there is increase in extra-cellular fluid which calls for 80% increase in the body sodium.
    When blood sodium level drops, kidney produces the hormone rennin, as a result of which sodium is retained in body.
    In case of oedema and hypertension sodium is restricted.

  11. Iodine:
  12. ICMR recommends additional requirement of 25 µg of iodine/day during pregnancy to normal requirement of 100- 200 µg of iodine / day. Iodine deficiency in mother can lead to abortion, still birth, congenital anomalies, increased perinatal mortality, cretinism and psychomotor defects.

Other nutrients:

S.No NUTRIENT Normal Adult woman Pregnant woman
1. Retinol (mcg) 600 600
2. ?- carotene (mcg) 2400 2400

Thiamine (mg)




Riboflavin (mg)




Niacin (mg)



6. Pyridoxine (mg) 2.0 2.5
7. Ascorbic acid (mg) 40 40
8. Folic acid (µg) 100 400
9. Vitamin B12 (µg) 1 1

The recommended intake of folic acid is based on its role in promoting normal foetal growth and preventing macrocytic anaemia of pregnancy. Folic acid is needed for the synthesis of essential components of DNA and RNA which increase rapidly during growth thereby increasing the requirements. Folic acid also is essential for the maturation of RBC s which must increase as the mothers blood volume increases.

Last modified: Monday, 24 October 2011, 6:40 AM