MORPHOLOGICAL CHANGES IN PLACENTA OF
ANAEMIC MOTHERS AND FOETAL OUTCOME .
Abstract -
Anaemia in female during pregnancy is very common , it affect maternal blood
leading to hypoxia ,results in Placental changes ;anaemia also exerts profound changes on the maternal
circulatory system and has serious effects upon both mother and foetus . Growth of fetus is intricately
linked with that of placenta , which is depended on both maternal nutritional status and the transfer of
nutrients as well as oxygen . study revealed morphological abnormalities due to hypoxia comprise of
some changes in placental structure like increased weight & diameter ,,thickning of placentas . Foetal
outcome also affected .Low birth weight baby and premature delivery increase .All these changes occure
due to compensatory phenomena for fulfill demand of o 2 in fetus .
AIMS & OBJECTIVES
The present study has been carried out with following aim and objectives:

To study morphology of placenta in non-anaemic mothers.

Find out morphological l changes in placenta of anaemic mothers.

Find out effect of anaemia (in mothers) over fetal outcome, gestational age and
baby birth.
BenefitsTo know, it is how much important to correct anemia in antenatal period to
prevent worst fetal outcome.
INTRODUCTION
Placenta is a fountainhead of human existence because it is a means for provide
nutrition and exchange of gases (o2&co2) in foetus. So it is a vital organ which is
absolutely essential for survival, growth & development of foetus. Through out the
gestation it under go continuously change in weight ,structure, shape and function in
order to support prenatal life.
It metabolic functions are complex , included foetal oxygenation, nutrition,
excretion endocrinological Function (synthesis of estrogen and progesterone)
detoxification of drugs, and act as a barrier by prevent many harmful bacteria and
substance from reaching to foetus . So it is most potent organ; but life span is shortest .It
is a most interesting but unfourtunately often ignored and misunderstood organ and
known to laity as ‘after birth’.
The term placenta was introduced by Realddus Columbus who used this latin
word for a ‘circular cake’ (Plakous = Placenta = cake).In the old testament the placenta
was considered as external soul . It is most easily available of all human organs but not
routinely subjected to detailed and critical scrutiny. The study of placenta is by necessity,
retrospective in Nature. Yet it provides reflection of the hazards, the foetus has been
subjected during its growth & development. The placenta is the most accurate record of
infant prenatal experience.
Placenta is a focus of increasing interest in modern obstetrics because significant
pathology afflict the placenta, often before affecting the foetus. Placental abnormalities
therefore can be an ‘early warning system’for foetal problems. The evaluation of planceta
thus become essential in high risk pregnancy. With nations commitment for ‘Health for
all’the successful outcome of all the pregnancy depended much to the horticulture of
placental tree.
Any diseases either associated or aggrevates with pregnancy,like
haematological disorder, diabetes &hypertension affect placenta, which also affected
morbidity and mortality statistics of pregnancy and foetal out come.
Anaemia is commonest haematological disorder that occurs in pregnancy.
Severity of anaemia among expectant mothers was judged by criteria suggested by WHO
and according to which a level of haemoglobin below 11 gm per dl during pregnancy is
an indication of anaemia. Its prevalence is about 60% among pregnant women over
worlds wide. The commonest cause of anaemia during pregnancy is iron deficiency
which may be due to nutritional deficiency, or increased demand. Disproportionate
increase in plasma volume during pregnancy causes dilutional or physiological anaemia.
The physiological anaemia starting from 6th week onwards but manifest by 8th week of
pregnancy, and progresses till 34th week and is aggravated if undernutrition taken by
mother. Anaemia leading to hypoxia ,results in placental changes; anaemia also exerts
profound changes on the maternal circulatory system and has serious or even lethal
effects upon both mother and foetus.
In present study we find out morphological & histological changes in placenta of
anaemic mothers and its effects on foetal out come.
Before advent of ultra sonography its evaluation was only possible after delivery.
The evaluation of placenta has thus become essential in high risk pregnancy.
In the whole world, perinatal mortality associated directly due to pregnancy is 18/
1000 live births. Whereas due to indirect causes is low. In India the rate is high 46/1000
live births .
Whether the factors determining the rate were related to the launch of newer
antibiotics, better nutrition of mother, ante natal care, more understanding of medical
disorders associated with pregnancy, is hard to determine. But in no means, the role of
PLACENTA remains central in the very basic outcome of 38-40 weeks of intra uterine
foetus.
As most of the perinatal foetal deaths, were related to the insufficient o 2 supply in
utero, placenta plays a pivotal role in the transport of o2 to the foetus. Though this is just
not the only role attributed to it, it remains major path finder for the ultimate goal of
healthy foetal outcome.
It was suggested that a test of placental efficiency is urgently required ( by U.S.G.
and colour doppler) and could be of fundamental importance in progress of foetus. To
establish such a test, placental structure and function must be considered together. The
study of development and structure of human placenta must be of wide interest.
Though the placenta is a organ of very limited life span, yet our information on the
factors limiting the span are imprecise, it performs number of function which in other
organs of body involve highly specialized tissues, including
transport of metabolites in two directions both to & from the foetus and synthesis of
important hormones and proteins.
High mortality and Morbidity was always associated with low Birth Weight
Babies in which the role of placenta become pivotal.
Very few research projects will involve and can offer better prospects of
successful co-operation between Anatomists, Physiologists, Clinicians and Obstetricians,
Pediatrics and Social Medicine.)
INTRODUCTION
Placenta is a fountainhead of human existence because it is a means for provide
nutrition and exchange of gases (o2&co2) in foetus. So it is a vital organ which is
absolutely essential for survival, growth & development of foetus. Through out the
gestation it under go continuously change in weight ,structure, shape and function in
order to support prenatal life.
It metabolic functions are complex , included foetal oxygenation, nutrition,
excretion endocrinological Function (synthesis of estrogen and progesterone)
detoxification of drugs, and act as a barrier by prevent many harmful bacteria and
substance from reaching to foetus . So it is most potent organ; but life span is shortest .It
is a most interesting but unfourtunately often ignored and misunderstood organ and
known to laity as ‘after birth’.
The term placenta was introduced by Realddus Columbus who used this latin
word for a ‘circular cake’ (Plakous = Placenta = cake).In the old testament the placenta
was considered as external soul . It is most easily available of all human organs but not
routinely subjected to detailed and critical scrutiny. The study of placenta is by necessity,
retrospective in Nature. Yet it provides reflection of the hazards, the foetus has been
subjected during its growth & development. The placenta is the most accurate record of
infant prenatal experience.
Placenta is a focus of increasing interest in modern obstetrics because significant
pathology afflict the placenta, often before affecting the foetus. Placental abnormalities
therefore can be an ‘early warning system’for foetal problems. The evaluation of planceta
thus become essential in high risk pregnancy. With nations commitment for ‘Health for
all’the successful outcome of all the pregnancy depended much to the horticulture of
placental tree.
Any diseases either associated or aggrevates with pregnancy,like
haematological disorder, diabetes &hypertension affect placenta, which also affected
morbidity and mortality statistics of pregnancy and foetal out come.
Anaemia is commonest haematological disorder that occurs in pregnancy.
Severity of anaemia among expectant mothers was judged by criteria suggested by WHO
and according to which a level of haemoglobin below 11 gm per dl during pregnancy is
an indication of anaemia. Its prevalence is about 60% among pregnant women over
worlds wide. The commonest cause of anaemia during pregnancy is iron deficiency
which may be due to nutritional deficiency, or increased demand. Disproportionate
increase in plasma volume during pregnancy causes dilutional or physiological anaemia.
The physiological anaemia starting from 6th week onwards but manifest by 8th week of
pregnancy, and progresses till 34th week and is aggravated if undernutrition taken by
mother. Anaemia leading to hypoxia ,results in placental changes; anaemia also exerts
profound changes on the maternal circulatory system and has serious or even lethal
effects upon both mother and foetus.
In present study we find out morphological & histological changes in placenta of
anaemic mothers and its effects on foetal out come.
Before advent of ultra sonography its evaluation was only possible after delivery.
The evaluation of placenta has thus become essential in high risk pregnancy.
In the whole world, perinatal mortality associated directly due to pregnancy is 18/
1000 live births. Whereas due to indirect causes is low. In India the rate is high 46/1000
live births .
Whether the factors determining the rate were related to the launch of newer
antibiotics, better nutrition of mother, ante natal care, more understanding of medical
disorders associated with pregnancy, is hard to determine. But in no means, the role of
PLACENTA remains central in the very basic outcome of 38-40 weeks of intra uterine
foetus.
As most of the perinatal foetal deaths, were related to the insufficient o 2 supply in
utero, placenta plays a pivotal role in the transport of o2 to the foetus. Though this is just
not the only role attributed to it, it remains major path finder for the ultimate goal of
healthy foetal outcome.
It was suggested that a test of placental efficiency is urgently required ( by U.S.G.
and colour doppler) and could be of fundamental importance in progress of foetus. To
establish such a test, placental structure and function must be considered together. The
study of development and structure of human placenta must be of wide interest.
Though the placenta is a organ of very limited life span, yet our information on the
factors limiting the span are imprecise, it performs number of function which in other
organs of body involve highly specialized tissues, including
transport of metabolites in two directions both to & from the foetus and synthesis of
important hormones and proteins.
High mortality and Morbidity was always associated with low Birth Weight
Babies in which the role of placenta become pivotal.
Very few research projects will involve and can offer better prospects of
successful co-operation between Anatomists, Physiologists, Clinicians and Obstetricians,
Pediatrics and Social Medicine.)
FULL TERM PLACENTA The human placenta is a flattened discoidal mass with an approximately circular or
oval outline with an average weight about 500 gms. (range 200-800 gms.), average
diameter 18 cms. (range15-20 cms) It is thickest at centre (The original embryonic pole)
and it rapidly diminishes in thickness towards its periphery. Average surface area of
placenta is about 30,000 mm. The human placenta is chorio-allantoic since it is
vascularzed by vessels homologous with allantoic vessels of lower mammals, Haemochorial because of nature of its membrane, villous because of its villi, deciduate because
maternal decidua is shed at birth along with it. It has got two surfaces and a margin-the
surface which was in contact with decidua basalis is designated as the maternal surface
and it appear rough, shaggey, raddish, and is subdivided by depressions of varying depth
into a number of irregularly shaped areas, the so called cotyledons, which vary
considerably in number, average about corresponding to major maternal vascular units
(Major branches of distribution of the umbilical vessels) and this is particularly well seen
in specimens which have been x-rayed after intravascular injection of radio-opaque
media. The grooves correspond to the bases of incomplete placental septa.
That surface of placenta which is directed towards the cavity of the ovum is
designated as the foetal surface. This surface is covered by smooth glistening amnion
with an umbilical cord attached near its centre. Mottled asppearence of the subjecent
Chorion, to which it is closely applied, can be seen through it. Beneath the amnion and
close to the attachment of the cord, the remains of the yolk sac can sometimes be
identified as a minute vesicle, up to 5 mm in diameter, with a fine thread – a vestige of
the yolk stalk- attached to it. The branches of umbilical vessel radiate peripherally from
the cord. The margin is limited by the fused basal and chorionic plates, and is continuous
with chorion laeve. The foetal membranes extend from the margins of placenta and
consist of the amnion, chorion and a thin layer of decidua.
villous placenta with associated fibrinoid matrix and the chorioamnison
together with a superficial layer of the decidua capsularis and parietalis. The chorioamion is continous with the placenta at its margin and constitutes the membranes.
FUNCTION OF PLACENTA
Main functions of the placenta are (a) exchange of metabolic and gaseous
products between maternal and fetal blood streams and (b) production of hormones.
1- Exchange of Gases
Exchange of gases, such as oxygen, carbon dioxide, and carbon monoxide,
is accomplished by simple diffusion. At term the fetus extracts 20 to 30 ml of oxygen
per minute from the maternal circulation, and even a short-term interruption of the
oxygen supply is fatal to the fetus. Placental blood flow is critical to oxygen supply.
Since the amount of oxygen reaching the fetus primarily depends on delivery not
diffusion .
2- Exchange of Nutrients and Electrolytes
Exchange of nutrients and electrolytes, such as amino acids, free fatty acids,
carbohydrates, and vitamins is rapid and increases as pregnancy advances.
3- Transmission of Maternal Antibodies
Maternal antibodies are taken up by pinocytosis by the syncytiotrophoblast
and transported to fetal capillaries. In this manner the fetus acquires maternal
antibodies of the immunoglobulin G(IgG) class against various infectious diseases
and obtains passive immunity against diphtheria, smallpox, measles, and others, but
not against chickenpox and whooping cough. Passive immunity is important because
the fetus has little capacity to produce its own antibodies until after birth.
4- Hormone Production
By the end of fourth month of the placenta produces progesterone in sufficient
amounts to maintain pregnancy if the corpus luteum is removed or fails to function
properly. In all probability all hormones are synthesized in the syncytial trophoblast.
In addition to progesterone, the placenta produces increasing amounts of estrogenic
hormones, predominantly estriol, until just before the end of pregnancy, when a
maximum level is reached. These high levels of estrogens stimulate uterine growth
and development of the mammary glands.
During the first two months of pregnancy the syncytiotrophoblast also
produces human chorionic gonadotropin (hCG), which maintains the corpus luteum.
This hormone is excreted by the mother in the urine, and in the early stages of
gestation. Its presence is used as an indicator of pregnancy. Another hormone
produced by the placenta is somatomammotropin (formerly placental lactogen) it is a
growth hormone-like substance that gives the fetus priority on maternal blood glucose
and makes the mother somewhat diabetogenic. It also promote breast development for
milk production.
5- Detoxification of drugs.
ANAEMIA AND PREGNANCY Healthy pregnancy is associated with marked changes in the circulating
blood that show wide variations. These physiologic adjustments include increase in the
blood volume and alternations in the interacting factors involved in hemostasis.
An understanding of haematologic problems in obstetric patients require
familiarity with the dramatic changes in the blood during normal gestation. Further more
these changes have special relevance to the most important and potentially hazardous
heamatologic problems of pregnancy namely anaemia.
Iron deficiency anaemia is the most common anaemia of pregnancy having a high
incidence of 30-70% of all pregnant women. The etiology of iron deficiency anaemia in
pregnancy and puerperium is related to several factor including iron loss incurred through
menstrual cycle of women of child bearing age, dietary deficiency in women of lower
socio ecomomic level, increase in blood volume in pregnancy, foetal demands and blood
loss at delivery .
Most body iron is contained in the haemoglobin of circulating and developing red
blood cells. During pregnancy the average requirement is 4 mg /day, rising from 2.5 mg
in early pregnancy to 6.6 mg/day in the last trimester. By far the greatest single demand
for iron is the need to expand the red cell mass. Iron is also required for the development
of foetus and placenta. Total extra
requirement being of the order of 700 - 1400 mg. Absorption of iron is enhanced in the
later half of pregnancy
During pregnancy the foetus requires about 400 mg of iron, an additional 150 mg
being needed for the developing placenta and growing uterus, about 270 mg of iron is
conserved in the absence of menstruation; making the total deficit small. It is important to
distinguish between iron deficiency anaemia and the reduction in erythrocytes and
haemoglobin caused by a physiologic increase in blood volume. Heamodilution alone,
therefore accounts for a reduction in haemoglobin concentration of 2 gms/ 100 ml .
The decrease in haemoglobin concentration is characterized as nutritional
anaemia, specially iron and folate deficiencies which are the most frequent anaemias
found in the first and second trimester
There are certain biochemical and physiologic mechanism by which the placenta
is able to support the growth and the development of the foetus in pregnancy anaemia .
Maternal anaemia evokes considerable placental hypertrophy which is significant
because it indicates an improvement of placental function and foetal well being.
The severity of anaemia among expectant mothers was judged by the criteria
suggested by WHO.
HAEMOGLOBIN LEVEL
10 gm/dl and above but below 11 gm/dl
- Mild Anaemia
7 gm/dl and above but below 10 gm/dl
- Moderate Anaemia
Below 7 gm/dl
- Severe Anaemia
The placenta is considered to be the most important foetal organ as it is
absolutely essential to foetal life . Foetus gets its nutrients from mother, so mother is put
to stress on her nutrients in pregnancy. With malanourished mother foetus is also affected
and the integrity of the placenta suffers.
FFECT OF ANAEMIA ON PLACENTAWong (1966) studied 60 placenta 30 from normal and 30 from malnourished
and found out that :1-
Average weight of placenta in normal new borns -463 gm
2-
Average weight of placenta in malnourished new borns – 339 gm.
3-
Foetal placental ratio in normal new born- 7.33
4- Foetal placental ratio in malnourished new born- 6.86
Ethics
Maternal anaemia was associated with placental enlargement (Biescher et al 1970)
. They studied placental morphology in more than 32 placenta of pregnant women in
different countries. However no positive correlation was found between the degree of
anaemia and placental size. He observed that in spite of high incidence of prematurity in
maternal anaemia . The average weight of placenta was greater than in control series.
Beischer et al (1970) noted that in severe maternal anaemia due to any cause , the
placenta tends to be unduly heavy , the foetus however often small and characteristically
the foetal-placental ratio was increased . These placenta were unusually histologically
normal , though there may be a minor degree of villous oedema .
Auinger W, Zeibekis N(1977) studied the influence of anaemia on the weight
of the newborn baby. Weight of baby in the anaemic group was less than in non-anaemic
group . In contrast the placenta showed an increase in weight .
Fox(1978) speculated that increased size of placenta in severe maternal anaemia
was indicative of compensatory mechanism by which the placenta attempts to over come
the diminished content of oxygen in the maternal blood.
Khanna et al (1979) examined 44 placenta from anaemic mother and 19
placenta from non-anaemic mothers . 70% of severely anaemic mothers had preterm
deliveries. There was significant decrease in placental weight , volume , surface area,
number of cotyledons in anaemic mothers. The incidence of ill defined cotyledons and
eccentric cord insertion were significantly increased in maternal anaemia.
Krishna M, Agrawal K N (1979) stated that the placental weight is
significantly reduced in pregnancy with anaemia . The decrease in total placental DNA in
anaemic women suggested that the reduced placental weight was due to decrease in cell
number . However these placenta also showed evidence of compensatory cellular
hypertrophy as indicated by increase in both weight and protein per cell.
Sala M A, Matheus M, Valeri V (1982) stated that there is regional variation in
the frequency of fibrinoid degeneration in human term placenta. The fibrinoid
degeneration is more common in region where hypoxia or relative stasis of blood occure ,
which stimulate the fibrinoid degeneration of villi .
Placenta from anaemic mothers having haemoglobin level below 10 gm%
haemoglobin were studied and compared. Significant alteration in villous vascularity,
increased endarteritis obliterans, increased syncytial knots and decreased calcification
have been observed in anaemic placentae (Gyatri Y. et al, 1983)
Rangnekar A.G. et al (1993) studied 10 placenta from anaemic mothers having
Hb% below 10gm% and 25 placenta from non anaemic mothers having Hb > 10gm%.
Observation were that the mean placental weight increased with gestational age and was
lower in anaemic mothers than in controls.
Reshetnikova O S , Burton G J (1995) studied placental histomorphometry and
morphometric diffusing capacity of the villous membrane in pregnancies complicated by
maternal iron deficiency anaemia. They concluded that there is reduction rather than an
enlargement of placental villous tree in cases of maternal anaemia . This may be because
of underlying malnutrition . The placenta adopts thinning of the villous membrane so
that diffusing capacity is maintained at normal levels.
Huang A , Zhang R, Yang Z (2001) stated that placental volume and absolute
volume of intervillous space or villi per placenta is significantly increased in anaemic
group. This placental hypertrophy associated with mild and moderate degree of iron
deficiency anaemia and enlargement of placenta is uniform physiological compensatory
growth. Enlargement in placenta are enough to ensure affected foetal growth.
Chavez D, Corral M (2003) stated that there is increase in placental weight and
placental weight /newborn weigh ratio in patients of anaemia but significantly effect on
the weight and height of newborn is not determined and change present in placenta are
enough to ensure affected fetal growth.
Charnock Jones DS, Kaurfmann P (2004) stated that fetoplacental angiogenesis
vary not only during the course of normal pregnancy but also in certain pregnancy
pathologies. Changes seen in hypoxia are in vascular endothelium , fibroblast and
placenta growth factors. Morphological changes focus on the patterns of angiogenesis
(branching and nonbranching) and a consistent set of morphometric descriptions covering
measures of the total capillary growth , villous capillarization and capillary size and
shape.
Effect of amaemia on Gross Morphology of placenta –
Regarding the gross morphology of placenta, the placental weight and the number
of placental cotyledons were significantly reduced in the severely anaemic mothers and
had direct relationship with the maternal haemoglobin level. However, placental volume
and surface area showed a constant relation to maternal haemoglobin, The high placental
ratio (Weight of placenta/ weight of fetus) found in these mothers suggested that the
weight of the newborn infant suffered more than the weight of the placenta in maternal
anaemia.
The reduced number of cotyledons in the placenta of mothers with severe anaemia
indicated a lesser degree of septation and probably a greater proportion of functioning
parenchyma, which could be an adaption to a physiological stress, resulting in an
improvement of placental function and foetal well being. This fact was also stated by
Anpej Huang et al also. They observed significant reduction in placental weight in
pregnancy anaemia. They observed that the number of cells in the placenta decreases and
hence the placenta weight also decrease due to the decrease in total placental cell DNA in
anaemic women.
The fact that there is reduced placental weight in anaemic mothers was further
supported by Usha Rusia et al. In their study foetal birth weight and placental weight
from severely anaemic women were significantly lower than those from mild and
moderate anaemic group of women. Both foetal birth weight and placental weight
showed a significant correlation with maternal haemoglobin concentration.
On the contrary enlarged placenta in maternal anaemia was observed by K.M.
Godfrey et al. They reported that anaemia and iron deficiency during pregnancy are
associated with large placental weight and a high ratio of placental weight to birth
weight. Increased placental weight was associated with maternal anaemia, and there was
positive correlation between maternal anaemia and placental weight. The author also
observed that placental hypertrophy or the enlargement of placenta appeared to be a
uniform proportional physiological compensatory growth. Studies indicate that placenta
size increased relative to infant size in pregnancies complicated by anaemia, but whether
this phenomenon reflected actual placental hypertrophy or failure of foetal growth to
keep up with placental growth remains to be determined.
It was summarized by T.T. Lao and W.M. Wong that on one hand the placental
weight and ratio have been shown to be increased with severe maternal anaemia, an
effect that has been attributed to maternal under nutrition, on the other hand it has also
been reported that the placental ratio is decreased in severe iron deficiency anaemia. they
also observed that in most recent demonstration there
was no difference in birth weight, placental weight or placental ratio between pregnancies
complicated by iron deficiency anaemia, and normal pregnancies but there were
significant histomorphometric differences in the placentae of both groups.
Foetal Outcome:
Most but not all small babies have small placentas. It was reported that
circumvallate placenta is associated with increased incidence of low birth weight possibly
because of distortion or constriction of the intravillous space.
Threshold for the level of Hb and consequently for oxygen transport below
which placental functions are impaired. This may explain in part the pathogenesis of
increased frequency of premature birth, foetal deaths and perinatal mortality in anaemia
in pregnancy. Kelly S. Scalon et al. relates that anaemia is an indicator for adverse
pregnancy outcome with preterm birth complications.
Maternal anaemia resulted in 12%-28% of foetal loss,30% of perinatal deaths and
7% -10% of neonatal deaths. The remaining births have around 50% chance of resulting
in a low birth weight baby. Anaemia during the second trimester was associated with
preterm birth, which is increased five fold for iron deficiency anaemia and double for
other anaemias. It is also associated with maternal morbidity. Maternal deaths to the
extent of 15%-20% are directly or indirectly due to anaemia.
It was seen that in cases of poor pregnancy outcome, examination of the
placenta may not only identify the exact cause but also give an indication of the time and
character of the insult.
Therefore histopathological examination of placental tissue is a valuable
tool in predicting the outcome of future pregnancies and their management.
FEOTOPLACENTAL WIGHT RATIO :
Westmark (1925) studied 19000 cases and found that there is some definite
correlation between weight of the foetus and weight of the placenta. Sinclair (1948)
claimed that placental foetal weight ratio lies between 1:6 to 1:8 after removing the loose
membrane. He plotted placental foetal weight ratio verses the weight of infant and
estimated a probable absolute minimum ratio (0.10-0.11) which would be compatible
with intrauterine life
Wiggleworth et al (1962) found that normally the placental weight and
birth weight ratio (placental coefficient) range between 0.10-0.18. He mentioned that
placental coefficient less than 0.10 and greater than 0.18 might be interpreted as a
relatively small or large placenta respectively.
Fox (1978) reported an increase in placental weight in the unfavorable
maternal environment such as preeclampsia and severe anaemia. He believed that
prematurely delivered placenta was usually smaller and lighter than full term, placental
coefficient was 0.3 between 28.30 weeks, 0.2 at 32 weeks and 0.5 at 34 weeks gestation)
Malik et al (1979) reported placental weight of 300 gms or even less in
11/25 (44%) of anaemia cases. Placental coefficient more than 0.2 was found 1/25 (4%)
in normal full term pregnancy and 3/25 in anaemic cases. Khanna S. et al (1979) studied
44 placenta from anaemic mothers, there was significant decrease in placental weight
volume, surface area and number of cotyledons in them) .
Lao T.T. Wong W.M. (1997) observed that the placental ratio is increased
in anaemia pregnancies, while studying 233 cases of mothers with anaemia due to iron
deficiency.
William L.A. et al (1997) found that placental weight to birth weight ratio
was significantly and positively associated with gestational age, female sex, Asian
parentage, increasing maternal mass index, increased maternal weight at
booking, lower socio-economic status, maternal anaemia, and increasing number of
cigarette smoked daily but concluded that ratio of placental weight to birth weight is not
an accurate marker of foetal growth.
MATERIAL AND METHOD
60 Placentas, neonates and mothers constituted the material for present
study. The mother delivered at Kamla Raja Hospital, Gwalior, associated with
G.R. Medical College. After delivery the full term placenta were collected
alongwith detailed case history and relevant investigations. The study was done in
Department of Anatomy in association with Department of pathology and
Department of Obstetrics and Gynaecology, G.R. Medical College Gwalior.
All the placentas were collected immediately after delivery. The placenta
were washed with normal saline and preserved in 10% saline for microscopic
examination.
This study was divided into 2 groupsGroup I Control Group
It comprised of 30 placentae from mothers having no signs and symptoms
of anaemia and their hemoglobin level were recorded to be more than 11gm%
Group II Study Group
It comprised of 30 placentae obtained from anaemic mothers whose
haemoglobin levels were less than 11 gm%. According to the WHO report (1989)
placenta divided into 3 groups depending on the severity of anemia
Group II a -Mild anaemia (Haemoglobin level 11 gm/dl–10 gm/dl)
Group II b - Moderat anemia (Hb level 10- 7gm/dl)
Group II c – Severe anemia
(Hb level < 7 gm/dl
Each group II contain 10 Placentae.
Criteria for selection of cases1- All cases belonging to age group 20- 35
2- Gestational age ranging from 28-42 weeks
3- We have taken primi as well as multi gravida.
4- They had no racial, cultural or environmental differences.
5- The mothers was not have any systemic disease (antipartum
haemorrhage, toxaemia of pregnancy, blood group incompatibility and any
systemic disease.
Gestational age was recorded by calculating by LMP (First day of last menstrual
period). per abdominal examination was done in every patient to know the gestational
weeks of pegnancy irrespective of whether patient was sure of LMP or not.
Gross examination of placenta 1. Examine as soon as possible after delivery in the fresh state.
2. Note the amount of blood and clots in the container and search for
separate pieces of membranes, cord and placenta.
3. Examine after delivery in the following order membranes, cord, fetal
surface and maternal surface.
4. The distance from the placental margin to the nearet point of rapture
was measured.
5. Membranes were examined for completeness, colour number of
cotyledons, calcification
insertion, decidual necrosis, retromembranous
haemorrhage, meconium staining, colour and transparency.
6. Attachment of umbilical cord to placenta is noted whether central,
eccentric or velamentous, number of umbilical vessels, true knots,
torsion,stricture, hematoma, thrombosis were examined.
Umbilical cord was cut one centimeter from the placental surface and the
membranes were trimmed off. Adherent blood clots were removed with a gauze
piece from the placenta and the sub chorionic vessels were emptied of blood by
gentle pressure. The placenta was blotted with filter paper and weighed. It was
measured by single pan weighing scale machine. Each placenta was weighted
accurately in gms.
Any abnormality in placenta such as accessory lobe or Bilobed placenta also
recorded.
The fetal surface was examined for colour, opacity, squamous metaplasia,
thrombosis of fetal surface vessels.
The maternal surface was examined for completeness, normal fissures,
laceration, depressed areas, retroplacental haemorrhage.
The maximum diameter, thickness in the centre, weight and shape was noted.
The schedule for study of Human Placenta and its relevance to mother
and foetus is covered as –
(a)
Placenta – gross Anatomy
1- Weight –
-Single pan physical balance
- By electric physical balance
2- Fibrosis – On the maternal surface near the periphery, Patchy areas
of fibrosis seen.
3- Umbilical cord
mantous.
insertion – Whether centric, eccentric or vela
(b) Mother :
1- Name
2- Husband’s Name
3- Age
4- Residence – Rural / Urban
5- Socio – economic status
6- Habit – Smoker/ Alcohol
OBSERVATION AND RESULTS
Present study was divided in two groupsGroup I – Control group (30 Cases)
Group II – Study group (30 Cases)
The study group was further divided according to severity of anemia.
Group II a – Cases of mild anaemia – 10 Cases
Group II b – Cases of moderate anaemia – 10 Cases
Group II c – Cases of severe anaemia – 10 Cases
Table 1 : Incidence of cases in various groups
Gro No. of cases
Percentage of cases
I
30
50
IIa
10
16.66
IIb
10
16.66
IIc
10
16.66
ups
Following factors were undertaken to accomplish the study1- MOTHER – Observation based on clinical examinations
(i) Parity
(ii) Gestational age
2- PLACENTA (i) Macroscopic Examination
(ii) Microscopic Examination
3- FOETAL OUTCOME (i) Birth Weight
(ii) Maturity level
1- MOTHERS
(i) Parity – It control group 67% were primi gravida and 33% were
multi gravida, whereas in anemic group 33% were found to be primigravida
and 67% were multi gravida.
TableII :
Incidence of cases of primi gravida and multi gravida in both
groups.
Groups
II
Primi Gravida
Multi Gravida
No.
%
No.
%
20
67%
10
33%
10
33%
20
67%
(ii) Gestational Age : The gestational age of mothers were calculated from
last menstrual period (LMP) and by doing per abdominal examinations in both
groups.
It was observed that in the control group 87% were delivered in the
gestational age of 37 to 40 weeks. Rest of the cases were found to be either less
than 37 weeks of gestation or more than 40 weeks of gestation, whereas in the
study group higher incidence was in the gestational age of less than 37 weeks
considering all the anemic group.
Table III Incidence of cases according to gestational weeks in various groupsGroups
<37 Weeks
No
37- 40 Weeks 40 - 42 Weeks
%
No
%
No.
%
I
2
6.5
26
87
2
6.5
II a
2
20
6
60
2
20
II b
4
40
4
40
2
20
II c
5
50
4
40
1
10
PLACENTA
Table I : Mean Placental weight and diameter in various groups.
Groups Mean placental weight (in gm)
Mean placental
Diameter (in cc)
I
480
16
II a
500
17
II b
480
16
II c
350
15
In Contral Group – Mean Placental weight – 480 gm .
In study group – Decrease in Placental weight with severity of anemia.
Table II – Incidence (in %) of various types of shapes in both groups.
Groups
Discoidal
Circular
Oval
Bilobed
I
77
23
0
0
II
63.5
32
3.23
1.27
In control group – Most common shape – Discoidal
In study group – Most common shape – Discoidal (63.5%) but circular shape is
more than study group because with severity of anemia surface area of placenta was
reduced making the shape circular.
Table III- Number of maternal cotyledons in various groups-
Groups Average No. of maternal cotyledons
I
17
II a
14
II b
11
II c
08
Number of cotyledons decrease with severity of anemia .
Fibrosis (Fibrin deposition)White patchy area of fibrosis were found in both group. It was present in 6% cases
of control, 20% cases in group II a, 25% cases in group IIb, and 65% cases in group II c.
Umbilical cord insertion
Table IV – Incidence of various types of umbilical cod insertion in both groups.
Type of U.C. Insertion
Control Group (%of cases)
Study Group (% of cases)
Central
67
40
Eccentric
33
58
Velamentous
0
2
In control group- Most common type of umbilical cord insertion – Central.
In study group – Most common type of umbilical cord insertion – Eccentric
FOETAL OUTCOME Foetal outcome categorized under the following headings(i)
Low birth weight by (L.B.W. baby) – L.B.W. baby was taken as one
whose birth weight was <2500 gm, irrespective of gestational age.
(ii)
Full term baby – A baby born anytime between 37-42 weeks of
gestation was considered as full term baby.
(iii)
Intrauterine death (I.U.D.)- In our study any foetal death beyond
28 weeks was termed as I.U.D.
(iv)
Premature baby- A baby born before 37 weeks of gestation was
considered as full term baby.
Table - Incidence of cases of foetal outcome in study group.
Groups
I.U.D.No.of Cases
Premature baby
No. of Cases
L.B.W. Baby
No.of Cases
F.T.N.D. No.
of Cases
I
0
0
0
30
II a
0
2
4
4
II b
1
3
3
3
II c
2
4
4
0
It was observed that in control group no cases were found of I.U.D.
prematurity , L.B.W. baby. 100% case were delivered as full term baby. While in
study group cases of I.U.D, cases of prematurity, and cases of L.B.W. baby
increase with severity of anaemia and cases delivered as full term baby decrease in
comparison to control group.
DISCUSSION
The present study was carried out on 60 placentas, newborn and mother.
Present study deals with effect of anemia on morphology and histology of
placenta.
Maternal data of parity and gestational age were also noted to see the effect
of these parameters on health of mother as far as anemia is concerned and
correlating its effects on placenta and foetal outcome.
It was found in all the cases of study groups that with the high parity (67%
of cases multigravida) severity of anemia increase. This was also observed by
other authors where the increase in parity leads to high grade of anemia. It
happens due to repeated blood loss in subsequent pregnancies.
It was found in all cases of study groups that total period of gestation
decreases with the severity of anemia. In our study 33.33% cases were noted at
less than 37 weeks. Vijaylaxmi et al also observed in their study of 1040 cases
that mothers delivered at < 37 weeks of pregnancy were 3.9% in non-anemic cases
and 26% in anemic cases. Further, gestation period decreases with severity of
anemia. Hughes have also reported similar findings of shorter duration of gestation
in pregnancy anemia.
The present study also correlates findings of high incidence of premature
(40%) low birth weight 40% and foetal loss (20%) with the increase in severity of
anemia. I was observed by kelly that woman with mild anemia had a 30-40%
increased risk and those with moderate to severe anemia had about 70% increased
risk of preterm birth. This have attributed this to either degenerative changes or
increase intervillous fibrinoid deposition where placenta could not further
compensate to the insult caused by hypoxia.
In present study we found that weight of placenta increase with mild
anemia but decrease in weight of the placenta with the severity of anemia (average
weight 443.33 gms of study group and 480 gms of control group).Usha Russia et
all studied 52 cases out of which 30% were of mild anemia. 40% were of moderate
and another 30% were of severe anemia and they found that the placental weight
of the severely anemic mothers were significantly lower than those of other two
groups. Small placental weight associated with anemic mothers was also reported
by wong et al Purnima explained that small placenta of severely anemic mother is
due to retarded growth of placenta with decrease in total placental DNA
suggesting decrease in cell number and thus reduction in size, where there is early
stop of cell division in anaemia (normally cell division stops after 36 week of
gestation). This was put by Ivan that placental weight is related linearly to infant
weight. Jeffrey supported by saying small placenta small baby.
Contradictory findings of heavier placenta are given by Beisehier and
Godfrey explaining that maternal anemia causes in adequate oxygenation of the
foeto placental unit and in term invokes physiological response resulting in
compensatory placental hypertrophy which is an adaptation to a physiological
stress. Where as it was TT Lao who stressed that it is the placental ratio (Placental
weight over baby weight), which increases with maternal anemia. Singhla also
reported that in high placental ratio of anemic mothers the infant suffered more
that the weight of the placenta.
So conclusion is that due to mild to moderate anemia in mother because of
hypoxia compensatory placental hypertrophy occur. But when anemia is sever,
placenta affected so much that it can not go under compensatory hypertrophy.
SUMMARY AND CONCLUSION
Anemia is most common nutritional disorder in world. Nutritional anemia
is most common among pregnant women. Severity of anemia among pregnant
women was judged by the criteria suggested by W.H.O.
In the present study morphological and histological changes in placenta of
anemic mother is undertaken to study effects of anemia on gestational age of
mothers, foetal outcome, morphology of placenta
Present study was carried out on 60 placentae. 30 placentae from mother
who are not anemic and 30 placentae from mothers who were anemic.
It was found that period of gestation decreased with severity of anaemia.
Various workers have attributed this to either degenerative changes or increased
intervillus fibrinoid deposition causing premature delivery where placenta could
not further compensate to the insult caused by hypoxia.
Prematurity and low birth weight increased in severe anemia. This is
attributed to early maturity of placenta, because of hypoxia.
Placenta from anemic mother have comparatively low weight. This is
attributed to retarded growth of placenta due to decrease in total placental DNA.
In present study number of cotylendons decreases with severity of anemia
(average no of cotyledons in control group 17, in study group 11) This was put by
olga. Olga in his study of placenta of anemic mothers found that there is reduction
in the number of lobes defined on maternal surface. which correlates with our
present findings. P.N. singhla attributed this reduced number of cotyledans in
placenta of anemic mothers as an indication of lesser degree of septation and
probably a greater proportion of functional parenchyma, which is an adaptation to
physiological stress.
Present study also showed that the umbilical cord insertion was more
towards margin. (In study group 58% of cases were eccentric whereas in control
group it was 33% with increase in severity of anemia, cords has eccentric type of
attachment. Hamilton Boyd and Mossman (1972) have described the attachment
of cord as central, eccentric, marginal (Battldore Placenta) and rarely velamentous.
In present study we found discoidal shape placenta (77% in control group
and 63.5% in study group) circular shape (23% in contral group and 32% in study
group) and oval 3.23% and bilobed or with accessory lobe 1.27% (Both found in
study group only) Thangula and vijayalaxmi found that with the severity of
anemia, surface area of placenta was reduced making the shape circular.
The present study also showed that incidence of fibrosis increase with increase in
severity of anemia. In control group 6% cases are found, whereas in mild anemia 20%
cases and in severe anemia 65% cases are found.
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