Hematological Disorderin pregnancy : Hematological Disorderin pregnancy Dr. Bambang Widjanarko, SpOG
Obstetrics & Gynecology Departement
School Of Medicine Muhammadiyah University
Jakarta
Physiological Changes : Physiological Changes One of the most significant hematological changes in pregnancy : blood volume expansion by mean of 50%
Plasma volume increases disproportionately compared with red cell mass : physiological decrease in hematocrite
Increased synthesis of some coagulation factors
Mild thrombocytopenia ( 90.000 /uL )
Definition of Anemia : Definition of Anemia A precise definition of anemia in women is complicated by normal differences in the concentration of hemoglobin beetween :
Women and men
White and black women
Pregnant and non-pregnant
Pregnant with iron supplements and who do not
On the basis of data presented in next table, anemia in non pregnant women is defined as hemoglobin concentration less than 12 g/dL and less than 10 g/dL during pregnancy and puerperium
Hemoglobin concentrations in 85 healthy women with proven iron stores : Hemoglobin concentrations in 85 healthy women with proven iron stores Scott DE, Prithcard JA : Iron deficiency in healthy young college women .
JAMA 199: 147, 1967
Cause of anemia during pregnancy : Cause of anemia during pregnancy Aquired :
Iron deficiency anemia
Acute blood loss
Inflamatory or malignancy
Megaloblastic anemia
Hemolytic anemia
Aplastic or hypoplastic
Hereditary
Thalassemia
Sickle cell hemoglobinopathies
Hereditary hemolytic anemia The two most common
Iron deficiency anemia : Iron deficiency anemia Most cases of anemia during pregnancy are due to iron deficiency and acute blood loss
Total body iron content in a healthy adult women : 3500 – 4500 mg
75% of iron is held in erythrocytes as hemoglobin
20% of iron is held in body stores, mainly in bone marrow and reticulo endothelial system as ferritin complex
5% of iron is held in muscles and enzym systems, mainly as myohaemoglobine
The life of erythrocyte is 100 – 120 days ; each days erythrocytes dies and release iron, and new erythtocytes are formed which used this released iron
Iron deficiency anemia : Iron deficiency anemia Each days a loss of 1 mg of iron occurs through the death of epithelial cells ; iron also loss each months in menstrual discharge, averages 1 mg a day
Non-pregnant women needs 2 mg of iron a day to maintain her iron balance
The average “mixed” diet provides 12 – 15 mg of iron of which 14 – 20% is absorbed
In the developing countries, diet consists mostly carbohydrates and vegetables, more dietary iron is needed daily as cereals contain phytates which prevent iron absorbtion
Hookworm, malabsorbtion of iron provide the explanation of higher prevalence of anemia in pregnant women in the non-industrialized countries
Demands of Iron during pregnancy : Demands of Iron during pregnancy Pregnancy imposed an increased demands for iron :
Woman’s larger red cell mass
Muscle formation, particularly that of the uterus
The uterus requires 425 mg of iron spread out over 40 weeks of pregnancy
The fetus requires 300 mg of iron, mostly in the last quarter of pregnancy
Placenta requires 25 mg of iron
Total iron demand during pregnancy is about 750 mg
Absorbtion of iron during pregnancy : Absorbtion of iron during pregnancy Demands of iron is not constant throughout pregnancy ; but is increases as pregnancy advances
The increased demands compensated for by an increased absorbtion iron from food
At 30 week’s gestation, 30% of ingested iron is absorbed
By 36 weeks’s gestation, 66% of ingested iron is absorbed ; 9 fold increase over the absorbtion of iron at 16 week’s gestation
Iron requirements in pregnancy : Iron requirements in pregnancy Note :
The net maternal needs are calculated from :
Replacement of iron lost from epithelial celss 1 mg/day
Increase in red cell mass and muscle development 1.6 mg/day
Less savings due to amenorrhoea 0.6 mg/day
Net daily needs 2.0 mg/day
Assumes a daily utilization rate of 20 – 25% of dietary elemental iron
From :
Jones LL, in Fundamentals of Obstetrics and Gynecology 7th ed Mosby Interrnational Ltd 1999
Diagnosis : Diagnosis Classical morphological evidence of iron deficiency anemia – erythrocyte hypochromia and microcytosis – is less prominent in the pregnant women ( compared with non-pregnant women with the same hemoglobine concentration )
Iron-deficiency anemia during pregnancy is the consequence primarily of expansion plasma volume without normal expansion of maternal hemoglobine mass
Diagnosis : Diagnosis Most cases of an anemia in pregnancy are due to iron deficiency ; but in southeast Asia, southern Europe and Africa , thalassemia and sickle cell anemia occur
In a few cases of severe anemia ( Hb < 6.5 g/dL ) , megaloblastic anemia may be present
All pregnant women should have a sample of blood tested for the presence of anemia at the first anv
The test repeated at the 30th and 36th wop
If clinical anemia is detected ( Hb < 10 g/dL ) the MCV and serum ferritine should be measured
The diagnosis of anemia in pregnancy : The diagnosis of anemia in pregnancy From :
Jones LL, in Fundamentals of Obstetrics and Gynecology 7th ed Mosby Interrnational Ltd 1999
Treatment of iron deficiency anemia : Treatment of iron deficiency anemia Depends on the severity of the iron deficiency and length of time available beetwen diagnosis and the expected date of the birth
If the anemia is detected before 36th wop and the Hb level is > 6.5 g/dL, oral iron may be given not exceed than 200 mg a day because of GI upset and the more severe the anemia the greater the amount absorbed
Treatment should be started with one-third of the dose required and gradualy build up
The iron tablet should be taken 8 hourly. A daily increase of about 1.5 mg/L may be expected over 2-week periode
Parenteral iron should be substituted for women are unable to take oral iron or if time to delivery is short
Treatment of iron deficiency anemia : Treatment of iron deficiency anemia Women who have severe anemia should also be given folic acid 5 mg a day, as the severe anemia may mask megaloblastic (folat-deficient) anemia
The lower the hemoglobin level the greater chance that the women has Megaloblastic anemia
Megaloblastic anemia :
7% neutrophils have five or more lobes
Confirmed by examining bone marrow film
Treatment of Megaloblastic anemia :
Folic acid 5 – 10 mg daily by mouth
Iron tablet
Should Prophylactic Iron Be Given ? : Should Prophylactic Iron Be Given ? Anemic women have a higher mortality, 3 – 5 times higher than for non-anemic women and stillbirth rate is increased 6-fold
A women whose diet is less balanced, or who lives in a developing country, needs iron
A women in the non-industrialized countries needs 120 – 140 mg Iron a day, because of the increased severity of anemia and the phytate in her diet which hinders absorbtion of iron
She should also take vitamin A 2.4 mg and 500 μg of folic acid daily From :
Jones LL, in Fundamentals of Obstetrics and Gynecology 7th ed Mosby Interrnational Ltd 1999
THALASSEMIA : THALASSEMIA Thalassemia are characterized by an impaired production rate of one or more of the peptide chains that are normal components of globin
The abnormal synthesis rate result in :
Ineffective erythropoiesis
Hemolysis
Anemia
The two major forms of thalassemias :
Impaired production of alpha chain → α Thalassemia
Impaired production of beta chains → Thalassemia
Incidence during pregnancy 1 in 300 to 500 Gehlbach DL, Morgenstern LL : Antenatal screening for thalassemia minor.Obstet Gynecol 71:801, 1988
THALASSEMIA : THALASSEMIA α Thalassemias, α chain accumulate and eventually precipitate causing severe anemia (Thalassemia major or Colley’s anemia)
Thalassemias may be either heterozygous (symptomless) or homozygous ( severe anemia )
Thalassemia can be excluded if the MCV > 80fl
MCV < 80 fl : indication for hemoglobin electrophoresis ; HbA2 > 3,5 indicates a Thalassemia trait
If either α – or Thalassemias is diagnosed, the father of the child should have a fool blood count and electrophorosis. If he is carrier of the trait, genetic counselling should be obtained
THALASSEMIA : THALASSEMIA A pregnant woman carrying the thalassemia trait has a 30% chance of becoming anemic and developing urinary tract infection
Thalassemia major in the fetus can be detected in the 1st quarter of pregnancy by chorionic villus sampling and in the 2nd quarter of pregnancy by sampling fetal cord blood ;
If the test are positive, termination of the pregnancy may be offered to the parents
Iso-immunization in pregnancy : Iso-immunization in pregnancy Rhesus iso-immunization is cause by a complex antigen
85% of Caucasians have the D antigen and are termed rhesus positive ; 15% rhesus negative
In the case of a Rh + fetus, it is blood cells may cross the placenta during pregnancy in sufficient numbers to stimulate antibody production against the rhesus antigen in the mother. In the next pregnancy, if the fetus is again rhesus +, the anti-D antibodies may across the placenta from mother to fetus and attach to antigen sites on the surface of the fetal erythrocytes – causes lysis of the fetal erythrocytes – shows as hemolytic disease
The Rhesus problem : : The Rhesus problem : Rhesus iso-immunization occurs only if a Rh – mother impregnated by a Rh + man. All pregnant women should be tested to determine their rhesus group at the initial antenatal visit If the women is Rh – and there are no anti-Rh antibodies detected, she should be retested at 28 and 36 wop
If Rh-antibodies are detected at titre of > 1:8 further assessment is made by amniocentesis for the level of bilirubin in amniotic fluid
If the mother has previously given birth to a severely affected baby, the level of iso-agglutinins is tested earlier than the 24 week, and if found to be raised, fetal cord blood sampling and the measurement of the fetal hematocrit is performed, as amniocentesis is inaccurate before 24 wop
The Rhesus problem : : The Rhesus problem : If the level of bilirubin is in the high zone, the baby severelly affected, may be hydropic dan die in utero if its haemoglobin is < 40 g/dL
If the pregnancy has advances to 32 wop, the pregnancy should be terminated by SC
If the level of bilirubin is in the mid zone, second amniocentesis is performed 2 – 3 weeks later, treatment being based on this result
Prevention : Prevention All Rh - , unsentized women , who abort and require curettage, are given an injection of 50 – 125 ug rhesus anti-D IgG within 72 hours of the abortion
All Rh - , unsentized women ( whose partner is Rh + or has unknown Rh status ), who require CVS,amnicentesis, have an ectopic gestation, antepartum hemorrhage,abdominal trauma or require external cephalic version, are given Rh anti-D IgG :
Dose before the 20th weeks is 50ug
Dose after 20th weeks it is 125 ug
Prevention : Prevention All Rh - , unsentized women , whose pregnancy progress to the 28th week, receive an injection of 125 ug Rh anti-D IgG , repeated at 34 weeks, unless the father of the fetus is Rh –
All Rh - , unsentized women, who give birth to a rhesus + baby, are given an an injection of 125 ug Rh anti-D IgG within 72 hours of the birth From :
Jones LL, in Fundamentals of Obstetrics and Gynecology 7th ed Mosby Interrnational Ltd 1999
Thank You : Thank You dr. Bambang Widjanarko, SpOG
Obstetrics & Gynecology Departement
School Of Medicine Muhammadiyah University
Jakarta