Q. My wife is 22 years old and pregnant. Her haemoglobin count is 9.4 and ESR is 80. During the first three months she was prescribed Folinal (folic acid 5 mg). Now the doctor has prescribed her Feronine 60 mg. Is there any risk because of her low haemoglobin count?
Pregnancy leads to many functional (physiological) and structural (anatomical) changes in the body. They occur due to the following:
(a) needs of the developing baby, placenta and the uterus and
(b) increasing levels of pregnancy hormones especially progesterone and oestrogen.
Anaemia is a condition in which the number of red blood cells (RBCs) or the amount of haemoglobin (Hb) is below normal for age and sex of the individual. It is usually discovered and quantified by measurement of the RBC count, haemoglobin (Hb) concentration, and haematocrit (Hct). Anaemia is suggested in pregnant women with Hb levels less than 11.5 g/dl. The most common cause of anaemia in pregnancy is deficiency of iron (~85% cases) and folic acid.
Even if a woman is not anaemic at the time of pregnancy, she may still develop anaemia as the pregnancy progresses due to several reasons. The fluid content of the blood (blood volume) increases up to 50% while the red cells increase by only about 20-30% resulting in haemodilution, i.e. relatively fewer red cells (and Hb) present in an increased volume of blood. This increase in blood volume helps in the exchange of respiratory gases, nutrients and other metabolic substances between the baby and the mother, increases perfusion of the uterus and kidney and it also compensates for the blood loss that will occur at the time of delivery. The magnitude of the increase in blood volume varies according to the size of woman, the number of pregnancies she has had, the number of infants she has delivered, and whether there is one or multiple fetuses.
There is also increased demand of the developing baby, which depletes the mother’s iron stores. There are certain risk factors for women being anaemic, and these include poor nutrition, inadequate gap between pregnancies, persistent nausea or vomiting in early pregnancy and twin pregnancy. The loss of iron (elemental) with each normal menses is around 12-15 mg. A normal diet must include 1.5-2 mg/day of elemental iron to compensate for menstrual losses alone. In pregnancy, 500 mg of additional iron is needed by the mother (to expand her red cell mass) while another 500 mg is needed for the baby and placental tissues. Thus, on an average, an additional 3 mg/day of elemental iron must be absorbed from dietary sources. The amount of iron absorbed by the body is only 10% of the total amount consumed, thus 30 mg/day needs to be consumed to meet the requirement.
The developing baby needs iron, folic acid and vitamin B12 from the mother for its growth. Women thus need to take supplemental iron and folic acid to meet the needs of the baby and hence iron deficiency is very common. If supplemental iron is not added to the diet, iron deficiency anaemia will result. Maternal requirements can reach 5-6 mg/day in the latter half of pregnancy. If iron is not easily available, the baby uses iron from maternal stores. Thus, the production of fetal haemoglobin is usually adequate even if the mother is severely iron deficient. This maternal iron deficiency may cause preterm labour and late spontaneous abortion. Deficiency of folic acid and vitamin B12 may also be seen in individuals on purely vegetarian diet.
An iron deficient mother can have premature labour, intrauterine growth retardation (poor development of baby), and severe anaemia due to normal blood loss during delivery and increased susceptibility to infection. The likelihood of postpartum transfusion may be reduced if a woman enters the birth with a higher haemoglobin level.