Transferrin levels in antenatal
women
Stephen S 1, Samatha P 2
1Dr. Sherin Stephen, Professor and Head, Department of Biochemistry,
Academy of Medical Sciences, Pariyaram, Kannur, Kerala, 2Dr Samatha P,
M Sc Biochemistry student, Department of Biochemistry, Academy of
Medical Sciences, Pariyaram, Kannur, Kerala, India
Address for
Correspondence: Dr. Sherin Stephen, Professor &
Head, Department of Biochemistry, Academy of Medical Sciences,
Pariyaram, Kannur, Kerala, Email:sherin.stephen@rediffmail.com
Abstract
Introduction:
During pregnancy, hemodilution leads to reduced hemoglobin, iron and
ferritin concentration with increase in total iron binding capacity.
Iron deficiency anemia is an important risk factor in pregnancy,
attributing to 16% of all maternal deaths in India. Transferrin
saturation is considered as the best marker of the iron supply for
erythropoiesis . The aim of the study is to evaluate the levels of
transferrin in antenatal women as a risk factor for iron deficiency
anemia. The specific objectives are to find out comparison and
correlation of the parameters used in the study. Methods: The present
study group consists of 100 patients and 25 controls. Serum
transferrin, total iron finding capacity and hemoglobin levels were
investigated. Serum iron binding capacity and transferring levels were
estimated by Ferrozine methods and hemoglobin by Cyanmethphotometric
method. Results:
The mean levels of transferrin in the patients in first trimester were
2.51+ 0.074 g/L, second trimester 2.87+ 0.058 g/L and 2.16 + 0.72 g/L
in controls, which was statistically significant. The levels of total
iron binding capacity in patients in the three trimesters were 358.36 +
10.73 μg/dl, 409.53 + 7.91 μg /dl and 471.57 + 12.10
μg /dl when compared to 308.48 + 10.09 μg /dl in controls
and was statistically significant. Conclusion:
The hemoglobin levels decreased significantly during each trimester
than controls along with significant P values in second and third
trimesters. Hence estimating the level of transferrin can be used as a
marker for assessing iron deficiency anemia in pregnancy.
Key Words: Transferrin,
Total iron binding capacity, Hemoglobin, Iron deficiency anemia
Manuscript received: 02nd
Feb 2016, Reviewed:
15th Feb 2016
Author Corrected:
23rd Feb 2016, Accepted
for Publication: 3rd March 2016
Introduction
The assessment of nutritional status for iron during pregnancy in
important because of the frequency with which deficiency of iron leads
to the development of anemia in pregnancy [1]. If iron stores are
reduced to the point of depletion of the reticulo endothelial iron, the
subsequent events are a decrease in serum iron and an increase in serum
iron binding capacity, leading to a decrease in percentage saturation
of transferrin. This change in erythropoiesis is first manifested as
transient development of normocytic anemia which is followed by
hypochromic microcytic anemia of iron deficiency [2]. Transferrin is
the non heme iron binding glycoprotein, major function of which is to
transport iron to reticuloendothelical cells and bone marrow, to reach
the immature red cells finally [3]. The physiological changes during
pregnancy include expansion of plasma volume, increased erythropoiesis
and increased demands of fetoplacental units for iron [4]. The values
of total iron binding capacity in both iron supplemented and non
supplemented women during pregnancy increased with increasing
gestation, but the values are greater in those women who did not
receive iron supplementation. Thus, there is definite effect on the
levels of transferrin in pregnancy with further increase when there is
concomitant iron depletion [5].
In the present study, transferrin was used as a marker to assess iron
deficiency anemia in pregnancy and its correlation with total iron
binding capacity and hemoglobin levels were also evaluated.
Materials
and Methods
The present study group consists of 100 patients who were pregnant and
25 normal healthy women of reproductive age were taken as controls.
Blood samples were taken from the study group admitted in Academy of
Medical Sciences, Pariyaram from April 2015 to September 2015 with
their consent, after obtaining ethical clearance. Detailed baseline
clinical data of each patient including age, height, weight, present
and past clinical complaints obstetric, family and personal history
were noted.
The following biochemical tests were done in patients and controls
included in the study like estimation of serum transferrin, total iron
binding capacity and hemoglobin. Investigations were done using
Systronics UV-Visible spectrophotometer and CELL-DYNR 3200 fully
automated analyzer. Serum total iron binding capacity (TIBC) and serum
transferrin level were estimated by Ferrozine method. Statistical
analysis is done using SPSS 17.0.
Result
In the study group 28 patients were in the first trimester and their
mean age was 26.96+3.77, 34 were in second trimester with mean age of
28.44+4.50 and 38 were in third trimester and their mean age was
26.37+3.48. Mean age of 25 controls were 24.64+2.59.
Variation Between Patients and Control
Table 1: Transferrin
Levels (g/L)
|
Group
|
N
|
Mean
|
Std Deviation
|
P value
|
|
Patients
|
|
|
First trimester
|
28
|
2.51
|
0.074
|
0.000.
|
|
Second Trimester
|
34
|
2.87
|
0.058
|
0.000
|
|
Third Trimester
|
38
|
3.30
|
0.084
|
0.000
|
|
Control
|
25
|
2.16
|
0.072
|
|
Table 2: TIBC Levels
(μg/dL)
|
Group
|
N
|
Mean
|
Std deviation
|
P value
|
|
Patients
|
|
|
First trimester
|
28
|
358.36
|
10.73
|
0.000
|
|
Second trimester
|
34
|
409.53
|
7.91
|
0.000
|
|
Third trimester
|
38
|
471.57
|
12.10
|
0.000
|
|
Control
|
25
|
308.48
|
10.09
|
|
Table 3: Hemoglobin
Levels (mg/dL)
|
Group
|
N
|
Mean
|
Std deviation
|
P value
|
|
Patients
|
|
|
First trimester
|
28
|
12.15
|
0.27
|
0.1080
|
|
Second trimester
|
34
|
11.73
|
0.37
|
0.001
|
|
Third trimester
|
38
|
11.37
|
0.63
|
0.000
|
|
Control
|
25
|
11.98
|
0.47
|
|
The transferrin levels in the patients during three
trimesters and those in controls were studied and were found to be
statistically significant in each trimester with p value of 0.000. The
mean value of transferrin in the patients of first trimester was
2.51+0.07g/L, those in second trimester 2.87+0.058g/L and third
trimester 3.30+0.084 g/L, when compared to controls, whose mean value
was 2.16+0.072 g/L (Table 1). The level of total iron binding capacity
progressively increased significantly during each trimester. The mean
value of total iron binding capacity was 358.36+10.73 μg /dl in
first trimester, 409.53+7.91 μg /dl in second trimester,
471.57+12.10 μg /dl in third trimester, whereas the mean value
in controls was 308.48+10.09 μg /dl and the p value (0.000) was
statistically significant in all the trimesters (Table 2). The mean
value of hemoglobin in the patients in first trimester was 12.15+0.27
g/dl (p=0.080), second trimester 11.37+0.63 g/dl (p=0.000) when
compared to the controls with a mean value of 11.98+0.47g/dl (Table 3).
Discussion
Iron deficiency anemia during pregnancy continues to be a common
problem accounting to 40% of maternal deaths, either directly or
indirectly from cardiac failure, hemorrhage or infection, in third
world countries. It can also result in an increase in the pre-natal
morbidity by increasing the chances for preterm deliveries and
intrauterine growth retardation [6,7]. In a normal pregnancy, a woman
needs 900 mg of iron for the maintenance of fetus and placenta, red
cell expansion and blood loss at delivery. The iron needs of pregnancy
have to be met by mobilizing the iron stores from hemoglobin of the
circulating red cells. Most women enter pregnancy with little or no
iron stores.
The stages of iron deficiency include depleted iron stores at the first
earliest stage and are manifested as reduced serum ferritin. Second
stage is iron deficiency without clinical anemia, where percentage
saturation of transferrin and serum iron decrease, whereas TIBC
increases. Iron deficiency is the final stage with low Hb and red cell
indices and a microcytic hypochromic blood smear [15]. Severe anemia
even predisposes to infection, particularly during puerperium,
increases the risk of thromboembolism and predisposes to decompensation
in mothers with cardiac or respiratory disease. It is also an important
factor in delayed general physical recovery, especially after caesarean
section and women at high parity and or low socioeconomic status [16].
Tranferrin is a glycoprotein, β globulin synthesized in liver
and carries two atom of iron , in the ferric state. Decreased
saturation of transferrin by iron enhances the release of iron from
intestinal mucosal cells [8]. In the iron requiring cells, transferrin
is taken by transferrin receptor –mediated endocytosis. In
antenatal women, due to the elevated steroid levels, the concentration
of transferrin increase which represents an increased rate of
production for its functional capacities along with no changes in its
degradation rate [9]. The clearance time of tranferrin bound iron from
circulation is mostly affected by the plasma iron level and activity of
erythroid marrow [10]. The serum levels of transferrin where highly
elevated in the patients under study in all the three trimesters. The
rate of erythropoesis also increases from first to third trimester as
the pool of erythroid cells requiring iron increases which leads to
progressive decrease in the clearance time of tranferrin from
circulation. The mean level of transferrin increased progressively in
the present study too from 2.15+0.074 g/L in first trimester to
2.87+0.058 g/L in second trimester and 3.30+0.084 g/L in the third
trimester, while in controls the mean value was only 2.16+0.072g/L. P
value was 0.000 in each trimester showing good statistical
significance.
The total iron binding capacity is an indirect measure of the
circulating transferrin. When the iron stores become depleted, the
serum iron begins to fall and total iron binding capacity increases.
Hence, TIBC is a sensitive indicator of early iron store depletion
[11]. Raza et al reported increasing levels of serum TIBC throughout
pregnancy [12]. In the patients included under this study, the iron
binding capacity also increased steadily from first to third trimester,
when compared to controls, with a significant p value of 0.000 in all
the three trimesters, indicating depleted iron stores.
During the full term pregnancy, the iron requirement amounts to
approximately 2.5 mg/day. In third trimester, it rises to 3.0 to 7.5
mg/day. These amounts are greater than those that can be absorbed from
even the best diets and stores may be insufficient to meet them. For
this reason, early diagnosis of anemia and iron supplementation is
frequently, a component of prenatal care. The half clearance time of
iron in the presence of iron deficiency is as short as 10 to 15
minutes; this value reflects the limit of iron delivery to the vital
organs for metabolism. According to Bengamin et al, iron deficiency
anemia was considered to exist during pregnancy, when serum iron level
is less than 50 μg/dL [13].
During pregnancy, reduction of hemoglobin level occurs due to plasma
volume expansion as a mechanism to improve arterial uterine flow to the
placenta [14]. The preferential expansion of plasma volume during
pregnancy when compared with red cell volume causes progressive
hemodilution up to 30th to 35th week which reduces the hemoglobin
concentration to 11 g/dL and haematocrit to 37%. According to the
definition of WHO, Hb concentration of less than 11 g/dL and a
hematocrit of less than 33% is defined as anemia in pregnancy. The mean
value of haemoglobin in the patients of present study decreased
gradually throughout the trimesters with a mean value of,
12.15+0.27g/dL(p=0.1080) in first trimester , 11.73+0.37 g/dL(p=0.001)
in second trimester, as well as 11.37+0.63 g/dL(p=0.000) in third
trimester, whereas the mean value in controls was only 11.98+0.047g/dL.
Conclusion
Thus, estimation of serum transferrin can be considered as an early
biochemical marker to asses iron deficiency anemia in antenatal women,
so that the maternal and foetal , morbidity and mortality can be
reduced to a great extent.
Funding:
Nil, Conflict of
interest: None initiated.
Permission from IRB:
Yes
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How to cite this article?
Stephen S, Samatha P, Transferrin levels in antenatal women. Int J Med
Res Rev 2016;4(3):420-423. doi: 10.17511/ijmrr.2016.i03.024.