Summary:
Anaemia in pregnancy is defined as a decrease of haemoglobin concentration and/or of hematoc-
rit by 2 standard deviations below normal values. WHO defines a haemoglobin concentration of
110 g/l and a hematocrit of 0,32 as the lower limits of the norm. Iron deficiency (ID) is defined as
a decrease of ferritin concentration below 12 mg/l.
Iron deficiency anaemia (IDA) is the most common anaemia in pregnancy, megaloblastic anaemia
- due to folate or vitamin B12 deficiency - are seen less frequently. Haemoglobinopathies, such as
beta-thalassemia minor and sickle-cell disease, are spread in the endemic areas. In the developing
countries, the aetiology of anaemia in gestation is often combined (malnutrition, malaria, chronic
infections, parasitosis etc.).
The prevalence of iron deficiency is very high in woman of fertile age, even in the developed
countries. the prevalence of anaemia in pregnancy varies depending on the demographic region,
trimester of gestation and parity. The prevalence of IDA in pregnancy is high (20-60%) but in the
developed countries milder cases predominate. A higher incidence of pregnancy anaemia is associated with the following factors of groups: lower social and economic status, history of irregular
uterine bleeding or hypermenorrhea, multiparity, multiple pregnancy, consecutive pregnancies
in short intervals, adolescent mothers, a vegetarian diet, and blood donorship.
A higher consumption of iron in pregnancy, due to accelerated erythropoesis and demands of
foetus and placenta which can not be compensated by usual diet, plays a major role in the
pathophysiology of IDA in gestation. There arises a negative iron balance, iron deficiency and
later on iron deficiency anaemia, which is deepen by peripartal blood loss and lactation in the
puerperal period.
Changes in the markers of iron stores are the laboratory signs first worsened: decreased ferritin
concentration, increased total iron binding capacity, and transferrin concentration.
Recently the serum transferrin receptor (s TfR) is being used, even in obstetrics, as a marker of
IDA (raised concentration), because it is not influenced by the acute phase reaction. The typical
picture of microcytic, hypochromic anaemia appears, when the iron deficiency worsens: decrea-
sed haemoglobin concentration, hematocrit, and red cell count. The ferritin concentration is still
the most valuable marker of the mobilizable stored iron in gestation, although its reliability is
limited (infection, gestational diabetes etc.). Clinically, anaemia in pregnancy is frequently latent.
The usual symptoms (fatigue, vertigo, headaches, palpitations, dyspnea) appear only in the case of
rapid or severe anaemia, most often in the puerperal period.
The mostly listed clinical risks associated with IDA in pregnancy concern the mothers health
(more operative and prolonged deliveries, more frequent need of transfusion, inclination to preec-
lampsia, lactation disorders, lower resistance to infection), foetal development (abortions, IUGR,
premature deliveries) and neonatal outcome (higher perinatal morbidity and mortality, worse
postpartum adaptation, disorders of psychomotor development). The results of many studies and
reviews are inconsistent. Nevertheless most of the authors and medical institutions recommend
iron supplementation of selected pregnant women in at least the second half of gestation.
IDA is treated with 100-200 mg of elementary iron orally a day, in the case of prophylactic substi-
tution with 60-80 mg a day. Retarded preparations containing ferrous iron ions are the most
advantageous. The addition of folic acid is indicated in megaloblastic anaemia (multiple pregnan-
cy, winter time). There is no causal therapy of hemoglobinopathies, repeated blood transfusions
are often needed to prevent dangerous haemolytic crises. Perinatology centres manage the prena-
tal diagnosis of these inhereted anaemia in foetuses of mothers at risk.
Key words:
anaemia, depleted iron stores, ferritin, folate deficiency anaemia, haemoglobinopathi-
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