Anemia in Pregnancy

Abstract

Anemia is the commonest hematological disorder that occurs in pregnancy. According to the recent standard laid down by ‘WHO’, anemia is present when the Hemoglobin (Hb) concentration in the peripheral blood is 11 gm/dl or less. The most common cause of anemia in pregnancy is lack of iron. Less often, it is caused by folic acid deficiency. In some populations, 80% of pregnant women are anemic. Those most at risk are women from low socio-economic groups and teenagers. Anemia is diagnosed by estimating the hemoglobin concentration and examining a peripheral blood smear for the characteristic red blood cell changes. Iron and folate supplementation is indicated during pregnancy to prevent the complications. DOI: http://dx.doi.org/10.3329/medtoday.v26i1.21314 Medicine Today 2014 Vol.26(1): 49-52

Full text

2014 Volume 26 Number 01 49
Abstract
Anemia is the commonest hematological disorder that
occurs in pregnancy. According to the recent standard laid
down by ‘WHO’, anemia is present when the Hemoglobin
(Hb) concentration in the peripheral blood is 11 gm/dl or
less. The most common cause of anemia in pregnancy is
lack of iron. Less often, it is caused by folic acid deciency.
In some populations, 80% of pregnant women are anemic.
Those most at risk are women from low socio-economic
groups and teenagers. Anemia is diagnosed by estimating the
hemoglobin concentration and examining a peripheral blood
smear for the characteristic red blood cell changes. Iron
and folate supplementation is indicated during pregnancy to
prevent the complications.
Key words : Erythropoiesis, Puerperium, APH, PPH, ANC,
LBW, IUD.
Introduction
Anemia is a lack of functioning red blood cells (RBCs) that
leads to a lack of oxygen-carrying ability, causing unusual
complications during life time1. These RBCs are produced in
the bone marrow. They have a life expectancy of about 120
days. Among other things, the body needs iron, vitamin B12 &
folic acid for erythropoiesis. If there is a lack of one or more
of these ingredients or there is an increased loss of RBCs,
anemia develops. Any patient with a Hb of less than 11
gm/dl to 11.5 gm/dl at the start of pregnancy will be treated
as anemic. The reason is that as the pregnancy progresses,
the blood is diluted and the woman will eventually become
anemic. The dilution of blood in pregnancy is a natural
process and starts at approximately at the eighth week of
pregnancy and progresses until the 32nd to 34th week of
pregnancy2.
Incidence
In tropical countries, the incidence of anemia3 in pregnancy
is about 40-80%.
In developed countries, it ranges between 10-20%.
It is responsibe for 20% of maternal death in developing
countries.
Classication of anemia in pregnancy
Grossly classied into two types4:
(A) Pathological anemia in pregnancy.
(B) Physiological anemia in pregnancy.
(A) Pathological Anemia is further sub-classied into
1. Deciency Anemia, e. g.,
-Iron deciency
-Folic acid deciency
-B12 deciency
-Protein deciency
2. Hemorrigic:
Acute hemorrhagic: Following bleeding in early month of
pregnancy or APH
Chronic hemorrhagic: as by hookworm infestation, GI
(gastrointestinal) bleeding.
1. Hereditary:
Thalassemias – Haemolobinopathies.
Hereditary hemolytic anemia – RBCs defects.
2. Bone Marrow insufciency: as by radiation, marrow
suppressant drugs.
3. Anemia of infection – as by malaria tuberculosis
4. Chronic diseases : as in nephropathies & neoplastic
disorders.
It is noteworthy that obstetricians are concerned with two
common types of anemia. They are :
5. Deciency anemia,
6. Haemorrhagic anemia
It has been found there is increased prevalence of anemia in
pregnancy in tropical countries.
This is due to
a. Faulty dietary habit,
b. Faulty absorption mechanism,
c. More iron loss due to sweating and repeated pregnancy
at short interval; prolonged period of lactation,
d. Infection : Chronic malaria, tuberculosis,
e. Excess demand of iron : pregnancy is an iron decit
state.
(B) Physiological Anemia
During pregnancy there is disproportionate increase in
plasma volume upto 50%, RBC 33% and Hb 18-20% mass.
In addition there is marked demand of extra iron during
Anemia in Pregnancy
Chowdhury S1, Rahman M2, Moniruddin ABM3
1. Corresponding Author: Salma Chowdhury MBBS, DGO
Senior Consultant (Gynae)
Central Police Hospital, Rajarbag, Dhaka
Email: dr.salmachowdhury@yahoo.com
2. Mizanur Rahman MBBS, FCPS
Associate Professor of Surgery
Faridpur Medical College, Faridpur
3. ABM Moniruddin MBBS, FCPS
Professor of Surgery
City Medical College, Itahata, Gazipur
Review Article

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pregnancy especially in the second half of pregnancy.
So, physiological anemia is due to combined effect of
hemodialution & negative iron balance.
Criteria of Physiological Anemia include5
- Hb% - 10 gm r less,
- R.B.C – 3.5 million/mm3,
- P.C.V – 30%,
- PBF – Normal morphology with central pallor.
Clinical features of iron deciency Anemia depends more on
the degree of anemia. Symptoms of anemia include lassitude,
feeling of exhaustion, weakness, anorexia, indigestion,
palpitation, swelling legs Signs of anemia include pallor,
glossitis, Stomatitis, edema legs, soft systolic murmur in
mitral area. Investigations are done to detect the degree of
anemia, the type of anemia the cause of anemia.
To ascertain the degree of anemia one must look for Hb%,
RBC count, PCV (Packed Cell Volume). Mild anemia means
Hb- 8-10 gm%; Moderate- less than 7-8 gm%; Severe – Less
than 7 gm%.
To determine type of anemia one must examine the PBF
(Peripheral Blood Film), hematological indcies like MCV,
MCH, MCHC, etc.
A typical iron deciency anemia shows the owing blood
values:
- Hb-less than 10 gm%
- RBC – less 4 million/ mm3
- PCV – less than 30%
- MCHC – Less than 30%
- MCV – less than 75% micro mole m3 (meter cube)
- MCH- less than 25 pg.
Serum iron is usally below 30 micro gram/ 100 ml. Total iron
binding capacity increases to 400 micro gram/100ml. Serum
ferritin falls below 15 micro gm/L.
To nd out the cause of anemia, the physician should
carefully follow the basic protocols.
- History taking,
- Physical examination,
- Routine examination of stool to detect helminthes or
occult blood,
- Urine is examined for the protein, sugar and pus cells,
- X ray chest in suspected cases of pulmonary tuberculosis;
but in case not responding to therapy, bone marrow study
should be undertaken.
- Blood for PBF & malarial parasites,
- Kidney function tests like BUN & s. creatinine, etc.
Differential Diagnosis of deciency anemias in
pregnancy:6
- Infection,
- Nephritis,
- Hemoglobinnopathies.
Treatment of anemia in Pregnancy:7
- Prophylactic
- Curative Prophylaxis includes
- Avoidance of frequent child birth by proper family
planning method.
Dietary prescription: Realistic balanced diet rich in iron and
portion like liver, meat, eggs, green vegetable etc. Adequate
treatment should be instituted to eradicate hook worm
infestation, control of dysentery, malaria, nephropathies &
excision of bleeding piles. Hb level should be estimated at
the 1st ANV and 30th and nally at 36th week.
Curative treatment:
- Hospitalisation, if Hb level is below 7.5 gram percent.
General treatment:
- Diet – balanced diet rich in protein, vitamins and iron
- Antibiotic for infective focuses, if any.
Specic Therapy as needed:
- Oral,
- Parental,
- Blood transfusion.
Depending on
- Severity of anemia,
- Duration of pregnancy,
- Associate complicating factor.
Iron Therapy:
Parenteral –
1. Intravenous,
a. Total dose infusion,
b. Multidose infusion,
2. Intramuscular:
- Iron dexran,
- Iron sorbital.
Estimation of total requirement:
0.3 X W ( 100-Hb%) gm of elemental iron + addition of 50%.
Improvement is expected withon 3-4 weeks.
Advantage of blood transfusion:8
- Increased O2 carrying capacity,
- Hb from heamolysed RBC,
- Stimulating by erythropoietin,

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- Supplies natural content of blood antibodies,
- Improvement is expected after 3 days.
Precaution:
- To prevent circulatory over load,
- Antihistamine for allergic episodes,
- Diuretic injection 20 mg Frusemide,
- Careful observation of respiration & crepitations at the
lung bases.
Place of blood transformation :
Indications:
- To correct blood loss,
- To combat PPH,
- Beyond 36 weeks and severe anemia, refectory anemia.
Quality and quantity of blood:
- Fresh and properly typed, grouped and cross matched;
only PCV are transfused.
- Quantity 80-100 ml at a time interval after 24 hours for
circulating readjustment.
Complications of severe anemia:9
During pregnancy-
- Pre-eclampisa,
- Recurrent infection,
- Heart failure,
- Preterm labour,
During labor-
- Uterine inertia,
- PPH,
- Cardiac failure,
- Shock.
During puerperium:
- Puerperal sepsis,
- Sub-involution,
- Failing lactation.
Management during labor:
In 1st stage-
- Patient. should be in bed and should be in a position
comfortable to her,
- Arrangement for oxygen,
- Aseptic condition is to me maintained.
In 2nd stage-
- Prophylactic low force/ vacuum delivery.
In 3rd stage-
- Active management.
Prophylactic antibiotic to prevent infection
- Iron therapy for at least 3 months following delivery.
Risk periods:
- At 30-32 weeks of pregnancy,
- During labor,
- Immediately following delivery.
Prognosis:10
Maternal aspect-
1. If detected early & proper treatment is instituted, anemia
improves promptly;
2. Substantial chances of recurrence in next pregnancy,
3. Contributes to about 2-% maternal death in developing
countries.
Fetal aspects-
- Baby born at term from severely anemic mother will not
be anemic at birth. But there is little or no reserved iron.
So anemia develops at neonatal period,
- Preterm labour,
- LBW (Low Birth Weight),
- IUD (Intra-Uterine Death).
Discussion
The most common cause of anemia in pregnancy is iron
deciency. It usually occurs due to low iron stores prior to
pregnancy. The growing fetus depletes what stores there are
and takes priority for any iron available. It is important to
remember that increased iron requirements continue after the
birth of the baby due to blood loss and breastfeeding. Less
often, anemia in pregnancy is caused by folic acid deciency.
In certain populations, pregnancy can be complicated
by sickle cell trait and anemia, as well as thalassaemias11.
These diseases, in which the red blood cells are abnormal,
present special problems in pregnancy. In some populations,
as many as 80% of pregnant women are anemic. They are
generally women from lower socio-economic groups in
developing countries as well as pregnant teenagers. Women
who experienced heavy periods and those who became
pregnant soon after the birth of a child are at particular risk
of becoming anemic in pregnancy. The symptoms such as
tiredness and general weakness will be similar to those of
any other type of anemia. In severe cases, the woman will
be short of breath even at rest. If the anemia is prolonged,
other signs of iron-deciency anemia may develop such
as a smooth shiny tongue and tenderness of the skin at the
corners of the mouth. However, these advanced signs are
rare. The diagnosis is made by examining a full blood count
and noting the low hemoglobin concentration as well as the
characteristic small, pale red blood cells under the microscope
(in the case of iron deciency anemia). The diagnosis of
iron deciency anemia can be conrmed by measuring the

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amount of storage iron as well as the levels of iron binding
proteins in the blood. The diagnosis of folate deciency is
conrmed by estimating the red blood cell folate levels. If the
anemia does not respond to iron treatment, additional folic
acid deciency should be suspected. A well balanced diet is
always recommended but iron and folate supplementation is
indicated in pregnancy. When the anemia is caused by lack
of iron, it is treated with iron supplements, preferably ferrous
sulphate tablets (300mg). These supplements should not be
taken more than twice daily, since the side effects of iron are
increased in doses of more than two daily. The side effects
are stomach upsets and constipation which are problematic
in pregnancy12. If the anemia is due to folic acid deciency, it
is treated with folic acid supplements (1 to 5 mg once a day).
As long as the anemia is treated and corrected, there should
be no problem.
In majority cases, the management of anemia in pregnancy is
easy & worthwhile if the pregnant women & their guardians
remain alert to protect the health of mother & baby. They need
to ensure proper antenatal check up, perinatal & postnatal
cares & follow relevent medical advice.
All pregnant women should be fully assessed at the start of
their pregnancy so that any problems such as anemia will be
picked up and treated.
References
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recommendations for the diagnosis and treatment
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3. Milman N. Prepartum anaemia: prevention and
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