A.MKUICAN . l o U H N A L Ol'* C l J N I C A L PATHOLOGY
Vol. 34, No. 3, S e p t e m b e r , 1960, p p . 247-253
Printed in
U.S.A.
EVALUATION OF BODY AND ORGAN WEIGHTS IN PERINATAL PATHOLOGY
I. NORMAL STANDARDS DEHIVJGD FROM AUTOPSIES
PETER GRUENWALD, M.D., AND HOANG NGOC MINH, M.D.
Departments of Obstetrics and Pediatrics, The Johns Hopkins University, Baltimore, Maryland
A peculiarity of perinatal pathology lies
in the fact that infants at birth vary greatly
in size and proportions of the parts of their
body, according to the length of gestation
and other factors. It is, therefore, very
important to have available standards by
which to judge autopsy findings in a given
infant. Stowens10 has stated that weights
and measurements are among the most
significant information to be obtained at
autopsy in pediatric pathology. Some
standards according to body weight are now
available. It is becoming increasingly evident, however, that there may be discrepancies between birth weight and gestational
age, and that these are of great scientific and
medical interest. It is, therefore, desirable to
have standards for groups classified by
gestational age as well.
The best existing data are those of Potter
and Adair,8 and these have been reprinted
in several textbooks. Unfortunately, the
manner of selection of cases is not stated
except that no infants surviving longer than
2 days are included. If no other selection
were made, it would be possible for an
institution highly reputed for treating certain conditions to have a material significantly weighted, for instance, by an excess
of cases of hemolytic disease of the newborn.
Only mean values, but no ranges are given.
The gestational age, which only appears in a
later version of the table, is apparently
calculated for given body weight groups; it
Received, February 29, 1960; accepted for
publication May 6.
Dr. Gruenwald is Associate Professor of Obstetrics and Pediatrics, and Dr. Minh is an Exchange Visitor from the University of Saigon, Vietnam .
This work was supported by research grant
B2371(C2) from the National Institute of Neurological Diseases and Blindness, U. S. Public
Health Service, Department of Health, Education, and Welfare.
can not be used to determine normal values
for a given gestational age. Another set of
data published by Coppoletta and Wolbach,3 is quite useful for older children; for
newborns it is useless, inasmuch as neither
birth weight nor gestational age are specified.
The values are too low for full-term infants,
and are presumably means of both full-term
and premature cases combined.
There is much more information regarding
the correlation of body weight and length,
as well as other external measurements, with
gestational age.7' 9' " Some of this is more
detailed than our data and may be consulted
to good advantage. The present data on
body length are given largely in order to
complete the picture obtained from 1 group
of cases. Crown to heel length is given; this
corresponds to standing height. Many
workers feel that crown to rump length can
be measured more accurately, and some
investigators have collected data on that
measurement.7' 3- n
Some workers, for instance Cardell,2 have
observed that it was necessary to provide
their own normal data to compare with
abnormal ones. This may be desirable either
if adequate pertinent data are unavailable,
or if control values obtained from deaths in
the same institution at or about the period
of study are thought to be more pertinent.
The disadvantage of this procedure is the
small number of cases available that may
give erroneous impressions of the range of
normal values.
There are suggestions that the normal
birth weight at term, and with it the weight
at the borderline of maturity, varies according to race. In particular, it has been suggested that Negro infants weigh somewhat
less than Caucasian infants of comparable
gestational age.1, I2 An attempt was made to
obtain pertinent information from the
present material, but the number of cases
known to belong to one or the other of the
247
248
GRUENWALD
two, was too small, and the results were,
therefore, not significantly different. I t
would be of basic significance to learn from
a sufficiently large body of data whether or
not any racial differences concern only body
weight or also some or all of the internal
organs.
A separate report 6 will deal with a comparison of body weight at autopsy and
weight of the placenta with similar data
obtained at birth on surviving infants.
MATERIAL
AND METHODS
The data to be presented here are obtained
from ca.ses selected as specified below, among
Vol. U
AND M I N H
somewhat more than 3000 autopsies. Weight
groups of 250 Gm. were used, inasmuch as
it was thought that, particularly in infants
weighing less than 2000 Gm., the use of
500-Gm. groups would pool cases of significantly different properties. The gestational age was used as stated in the patient's history prior to delivery, and only
when a calendar date was given. This obviously includes erroneous information. On
the other hand, it was thought that the
purpose would be defeated if the gestational
age were corrected or omitted when the
infant's birth weight seemed to disagree with
it. Close investigation of pertinent cases,
TABLE 1
W E I G H T S AND L E N G T H S O P N E W B O R N I N F A N T S AND T H E I R ORGANS, BY G R O U P S O P
VARIOUS BODY W E I G H T S
Body
Weight
Body
Length
Heart
Lungs,
Combined
Spleen
Liver
cm.
Gm.
Gm.
Gm.
Gm.
Gm.
317
29.4
5.0
12
1.3
±2.5
±1.6
6.3
±5
19
2.6
±1.7
3.2
±1.8
7.7
±6
24
±0.8
2.0
±1.2
26
±10
39
±12
±1.5
±2.0
±8
30
±1.5
3.4
47
±12
±9
34
±1.8
3.5
±1.6
4.0
±1.7
±2.6
10.4
Gm.
500
750
1000
1250
Adrenal
Kidneys,
Glands,
Combined Combined
Number
of Cases
311
295
32.9
±3.0
35.6
217
±3.1
3S.4
±3.0
1500
167
41.0
±2.7
1750
14S
42.6
±3.1
44.9
2000
140
2250
124
2500
120
2750
13S
47.3
±2.3
48.7
3000
144
±2.9
50.0
3250
133
3500
106
3750
57
4000
31
4250
15
±2.8
46.3
±2.9
±2.9
50.7
±2.6
51. S
±3.0
52.1
±2.3
52.4
±2.7
53.2
±2.5
9.6
±3.3
11.5
±3.3
12.S
±3.2
14.9
±4.2
16.0
±4.3
17.7
±4.2
19.1
±3.S
20.7
±5.3
21.5
±4.3
22.8
±5.9
23.8
±5.1
25.8
±5.3
26.5
±5.3
2.6
±11
40
4.3
±2.0
5.0
±13
44
±2.5
6.0
±13
4S
±15
4S
±14
±2.7
7.0
51
±15
53
±13
59
±1S
63
±17
65
±15
67
±20
68
±16
±3.3
8.5
±3.5
9.1
±3.6
10.1
±3.3
11.0
±4.0
11.3
±3.6
12.5
±4.1
14.1
±4.0
13.0
±2.5
56
±21
65
±1S
74
±20
82
±23
88
±24
105
±21
117
±26
127
±30
145
±33
153
±33
159
±40
180
±39
197
±42
4.5
±1.S
5.3
±2.0
Thymus
Brain
Gestational
Age
Gm.
Gm.
Gm.
Weeks, Days
5.4
±2.1
2.2
±0.S
7.8
2.8
±1.3
3.7
70
±1S
107
±3.4
12.9
±3.9
14.9
±4.2
17.4
±4.7
±2.0
4.9
±2.1
6.1
±2.7
6.8
±3.0
7.9
±3.4
S.2
5.3
±2.0
6.0
18.8
±5.0
20.2
±2.3
7.1
±2.8
7.5
±2.7
±4.9
22.6
±5.5
24.0
±5.4
24.7
±3.4
8.3
±4.4
±5.3
27.3
±6.6
28.0
±6.5
29.5
±6.S
30.2
±6.2
±4.3
11.6
±4.4
8.3
±2.9
9.2
±3.4
9.8
±3.5.
10.2
±3.3
10.8
±3.4
12.0
±3.7
30.7
±5.8
9.6
±3.8
10.2
12.S
±5.1
13.0
±4.8
11.4
±3.2
11.7
±3.7
23,
±2,
5
3
±27
26,
±2,
0
6
143
±34
174
27,
5
±3,
29,
1
0
±3,
31,
±2,
32,
0
3
3
4
±2,
34,
6
6
±3,
36,
±3,
38,
±3,
39,
±2,
40,
±2,
40,
2
4
0
0
2
2
2
0
1
4
±1,
40,
±1,
40,
±2,
41,
6
4
5
6
3
4
±1,
41,
±2,
3
2
1
±3S
219
±52
247
±51
281
±56
308
±49
339
±50
362
±48
380
±55
395±53
411
±55
413
±55
420
±62
415
±38
Sept. I960
PJDJtlNATAL
BODY AND ORGAN
249
"WEIGHTS
TABLE 2
W E I G H T S AND L E N G T H OV N E W B O R N I N F A N T S AND T H E I R ORGANS BY GESTATIONAL A G E *
Adrenal
Kidneys,
Glands.
Combined Combined
Gestational
Age*
Number
of
Cases
Body
Length
Bodv
Weight
Heart
Lungs,
Combined
Spleen
Liver
cm.
Gm.
Gm.
Gm.
Gm.
Gm.
Gm.
24
10S
31.3
±3.7
33.3
±3.6
36.0
±4.2
37.S
±3.7
40.5
±4.5
42.S
±4.5
45.0
±4.0
47.2
±4.6
49.8
±3.9
50.3
±3.6
52.S
±2.8
63S
±240
845
±240
1020
±340
1230
±340
14S8
±335
1838
±530
2105
±000
2678
±75S
3163
±595
3263
±573
3690
±800
4.9
±1.6
6.4
±2.0
7.6
±2.3
9.3
±3.3
11.0
±3.7
13.4
±3.9
15.1
±4.8
18.5
±5.5
20.4
±5.3
21.9
±6.2
25.S
±4.5
1.7
±1.1
2.2
±1.5
2.6
±1.4
3.4
±2.0
4.1
±2.1
5.2
±2.1
6.7
±3.0
S.8
±4.2
10.0
±3.9
10.2
±4.3
11.2
±4.1
32
±15
39
±15
46
±10
53
±19
05
±22
74
±27
87
±33
111
±40
130
±45
139
±45
149
±35
2.9
±1.4
3.4
±1.5
3.7
±1.7
4.2
±2.2
4.3
±2.3
5.5
±2.3
0.4
±3.0
S.4
±3.5
S.6
±3.4
9.1
±4.0
9.3
±4.4
20
28
143
139
30
148
32
150
34
104
30
87
38
102
40
220
42
112
44
42
17
±6
IS
±0
23
±7
28
±11
34
±11
40
±13
40
±10
53
±15
50
±15
56
±18
60
±17
Thymus
Brain
Gm.
Gm.
Gm.
6.4
±2.6
7.9
±2.9
10.4
±3.6
12.3
±3.9
14.5
±4.8
17.7
±5.3
21.6
±6.7
23.S
±7.0
25.6
±6.5
25.S
±7.5
2S.4±7.5
2.7
±1.4
3.0
±2.3
3.S
±2.1
4.6
±2.3
5.5
±2.3
7.5
±3.8
S.l
±4.2
9.7
±4.8
9.5
±4.4
10.4
±4.4
10.3
±4.7
92
±31
111
±39
139
4S
166
±55
209
±44
246
±5S
2SS
±62
349
±56
362
±55
405
±54
417
±55
* Gestational age is expressed in weeks from the last menstrual period.
such as I example previously published,6 has
revealed that what might seem to be inaccuracies are, in some instances, true and
significant discrepancies. These would be
lost to further study if the values were
corrected in any way after the infant's birth.
In addition to a presentation of the data
consisting of mean and standard deviation,
methods will be suggested by which abnormal data in single cases or groups of
cases may be plotted against the normal
values. Figures for macerated stillborn
infants, and for certain groups of abnormal
infants, will be reported at later dates.
In addition to autopsy records of Johns
Hopkins Hospital, data from autopsies performed previously by, or under the supervision of one of us (P. G.), were used.
Moreover, several colleagues added information from their records. Stillborn infants and
those surviving for 3 days or less were used,
except for the following groups: intrauterine
maceration; infants of diabetic mothers;
hemolytic disease of the newborn (all forms
of isoimmunization); multiple births; severe
malformation; intrauterine malnutrition (a
small group diagnosed by us prior to this
study); and pre-eclampsia (when stated; it is
likely that many cases were not excluded
inasmuch as information may be incomplete). The criteria for inclusion of the
gestational age were mentioned above. It
should be noted that this is counted from
the onset of the last menstrual period. Except in rare instances in which more detailed
information is available, 2 weeks should be
deducted in order to arrive at an estimate of
the true gestational age. The numbers of
cases used are given in Tables 1 and 2. Inasmuch as not all data were available in each
instance, the numbers on which values for
organ weights are based may be somewhat
smaller. Cases in which a large number of
data were missing were entirely excluded.
We have excluded from Tables 1 and 2 our
calculated values below the weight group of
500 Gin. or the gestational age group of 24.
weeks because information is likely to be
250
G R U E N W A L D AND MINl-I
biased. In many hospitals the borderline of
body weight above which autopsies are
performed, falls within these groups, and
it is likely that only the larger members of
these groups are autopsied.
The figures identifying the weight or age
groups in the far left columns in Tables
1 and 2 are median values. All cases are
allocated to the nearest of these values
higher or lower. Those exactly halfway
between 2 values are allocated to the higher
one. This creates a slight deviation in the
case of gestational age that is frequently
given in full weeks. It is likely, therefore,
that the data for each group are the average
for that particular week and the preceding
one, or for a group one-half week below the
given figure. Thus, the 38-week column
includes all cases from 37 weeks inclusive up
to just under 39 weeks. In practice, this
means mostly cases listed as 37 or 38 weeks.
The data are, therefore, likely to represent
an average gestational age of 37}4 weeks.
In the case of lungs, adrenal glands, and
kidneys, the combined weight of the 2 organs
is given.
All information was transferred to punch
cards where it was grouped in increments as
follows:
Body weight
250 Gm.
Body length
2 cm.
Weight of heart
2 Gm.
5 Gm.
Weight of lungs
Weight of spleen
2 Gm.
Weight of liver
20 Gm.
Weight of adrenal glands
2 Gm.
Weight of kidneys
2 Gm.
Weight of thymus gland
2 Gm.
Weight of brain
25 Gm.
Gestational age
2 weeks
Mean values and standard deviations were
calculated in the usual manner. The gestational age given in the far right column of
Table 1 is calculated for each weight group.
This information should not be used in order
to locate data for a given gestational age;
Table 2 should be used instead.
DISCUSSLON
The data summarized in this paper were
obtained chiefly as an aid to pathologists for
Vd. 34
the proper interpretation of their autopsy
findings. The organ weights as plotted
against body weight agree very well with the
data of Potter and Adair.8 The principal
addition in this area consists of the determination of the standard deviation and the
use of 250-Gm. increments of body weight.
It should be noted that the body weights
are those obtained at autopsy. In a subsequent publication,6 data will be presented
that demonstrate that this weight is significantly lower than the birth weight of
surviving infants of the same gestational
age. It would have been interesting to
tabulate the birth weight of the autopsied
infants in our series. Unfortunately, this
information is not available in the majority
of instances. The factors responsible for the
difference in weights will be discussed elsewhere. It might only be mentioned here that
the following are probably the most significant ones: early postnatal weight loss of
liveborn infants, and postmortem weight
loss (which has frequently been observed in
many laboratories).
Organ weights based on gestational age
have, to the best of our knowledge, not been
available. There seems to be a deep-rooted
mistrust of dates given by many of the
patients, and they are no doubt erroneous
in some instances. It is only fair, however, to
note that an overly pessimistic view of the
value of the date of the last menstrual
period, as reported by the patient, has for a
long time hampered the investigation of
those instances in which a discrepancy with
the birth weight seems to exist. The potential
significance of studies along this line was
previously emphasized.5 It is hoped that the
data presented here in Table 2 will aid in the
evaluation of those cases in which the birth
weight, or weight at autopsy differs significantly from that expected for the stated
length of gestation.
In using the present tables, one should
remember that the range included within 1
standard deviation on both sides of the
mean, comprises approximately two-thirds
of all cases; the range of ± 2 standard deviations includes approximately 95 per cent of
the cases used in calculating the data. It
should also be clear that information derived
from autopsies is based on average, but not
Sept. I960
PERINATAL BODY AND ORGAN WEIGHTS
necessarily normal material. In fact, not
even all of the abnormal conditions listed
above have been completely excluded,
inasmuch as they are not always diagnosed.
Cases of intrauterine malnutrition, for
instance, are not customarily diagnosed as
such in many hospitals and an unknown
number of them have, therefore, not been
excluded. In view of this, it may be suspected
that the ranges indicated by the standard
deviation are greater than they might be if
all cases were normal for the particular
measurement under consideration. I t may,
therefore, be adequate to consider the range
of ± 1 standard deviation as the norma!
range for data obtained at autopsy even
though it includes only approximately twothirds of the cases. This, however, will be
left to the discretion of the users of our
tables.
F I G . 1. An example of the use of the standards
listed in Tables 1 and 2, in order to characterize
d a t a of an abnormal infant. The patient was one
with
severe
intrauterine
malnutrition,
as
described in detail elsewhere. 6 Each measurement
is entered according to its deviation from t h e
mean, in terms of multiples of the respective
standard deviation. T h u s , t h e distance between
adjacent horizontal lines represents different
amounts of weight for each organ. T h e open circles
represent d a t a by body weight, the solid dots by
gestational age.
251
The difficulties of obtaining truly normal
values have been painfully obvious in studying the experimental expansion of lungs.4
Nearly all lungs of stillborn and newborn
infants contain more than the normal
amounts of fluid in the air spaces and interstices. In addition, there are great variations
in the filling of the blood vessels. As a result,
it is impossible to define a unit amount of
lung tissue based on weight at autopsy. The
present lung weights are included only for
the sake of completeness, and not because
they are thought to be normal values. They
include large numbers of cases of intraalveolar or interstitial edema, as well as
instances of pneumonia and of the respiratory distress syndrome (hyaline membrane
syndrome), and perhaps other conditions
affecting the weight. Normal lungs are
seldom seen in perinatal pathology. Thus,
it is likely that lungs affected by the respiratory distress syndrome fall within 1
standard deviation of our mean even though
they are truly heavier than normal, only
because man}' similar cases were included
in the group from which our data are derived.
Data, such as the ones presented here, may
be utilized in various ways. A few suggestions may be made. We have prepared
graphs for the data contained in each of the
horizontal lines in Tables 1 and 2, including
± 1 standard deviation.* The weights of a
particular organ in a group of cases of a
given abnormal condition may be plotted in
the appropriate graph, and a trend may
thus be demonstrated. Another method is
illustrated by figure .1. In contrast to the one
just mentioned, in which many measurements for 1 organ may be examined, the
second method allows the plotting of all
data from 1 case or a few cases against the
respective means and standard deviations.
The basic graph is calibrated along the
ordinate in multiples of the standard deviation, positive and negative, regardless of
its numerical value in any 1 organ. Each
measurement in the given case is represented
not by its numerical value, but by its devi* These graphs are not reproduced hero because
they would bo useful only if each occupied a full
page, which does not seem to bo feasible.
252
Vol. 34
G R U E N W A L D A N D M1NH
ation from the mean in terms of multiples or
fractions of the standard deviation. Thus,
in the example illustrated in Figure 1, a
value of 1 would mean approximately 55
Gm. above or below 362 Gm. for brain by
gestational age (40 weeks), 51 Gm. above or
below 247 Gm. for brain by body weight
(1750 Gm.), 5.3 Gm. above or below 20.4
Gm. for heart by gestational age, and so
on. In this manner, all data relating to 1
case can readily be surveyed. It will be noted
that even though the example is an extreme
case of intrauterine malnutrition, 6 many of
the data are not far from the range of ± 1
standard deviation. This confirms what was
stated above, namely, that normal values
are likely to be well within 1 standard deviation of the mean.
SUMMARY
Standards of body length and weight, and
organ weights of stillborn and newborn
infants have been determined in relation to
body weight and gestational age. This information may be used in evaluating autopsy
findings in perinatal pathology.
Discrepancies between body weight and
gestational age should not be dismissed
without further investigation as owing to
inaccurate information concerning the length
of pregnancy. Significant pathologic changes
will then become apparent that have frequently been overlooked in the past. The
present data relating various measurements
to gestational age may be used in evaluating
such cases.
The limitations of the significance of
"normal" measurements in perinatal pathology are discussed.
additional proque illos pare sufficientemente
explicibile per le supposition que le information relative al duration del pregnantia
esseva erronee. Si tal discrepantias es studiate plus criticamente, significative alterationes pathologic va esser recognoscite le
quales esseva frequentemente negligite in le
passato. Le hie presentate datos relative a
varie mesurationes in relation al etate gestational pote esser utilisate in le evaluation de
tal situationes.
Es discutite le limitationes del signification
de mesurationes "normal" in pathologias
perinatal.
Acknowledgments. T h e authors are indebted t o
Drs. W. Blanc of the Babies' Hospital, ColumbiaPresbyterian Medical Center, New York City; K.
Benirschke of the Boston Lying-in Hospital;
H. W. Mayberger of t h e Glen Cove Community
Hospital; L. Strauss of t h e M o u n t Sinai Hospital,
New York; and T . Weinberg of the Sinai Hospital,
Baltimore, for contributing d a t a . The authors also
wish to thank T . M. Prazier for valuable help
with t h e statistical evaluation of their d a t a .
REFERENCES
1. BAUMGARTNER, L., P E S S I N , V., W E G M A N , M .
E., AND PARKER, S. L . : Weight in relation
to fetal a n d newborn mortality. Influence
of sex and color. Pediatrics, 6: 329-341,
1950.
2. CARDELL, B . S.: T h e infants of diabetic
mothers. A morphological study. J . Obst.
& Gynaec. Brit. E m p . , 60: 834-853, 1953.
3. COPPOLETTA,
J . M . , AND WOLBACH, S. B . :
Body length and organ weights of infants
and children. A study of t h e body length
and normal weights of t h e more i m p o r t a n t
vital organs of t h e body between birth and
twelve years of age. Am. J . P a t h . , 9: 5 5 70, 1933.
4. GRUENWALD, P . : Pathologic aspects of lung
expansion in m a t u r e and premature newborn infants. Bull. New York Acad. Med.,
32: 689-692, 1956.
5. GRUENWALD, P . , AND C O N N E R , J . N . : ChrOIlic
SUMMARLO
IN INTEKLLNGUA
Esseva determinate standards de longor e
de peso corporee de morte—e neonatos e del
pesos de organos in relation al peso corporee
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esser usate in le evalutation de constationes
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Discrepantias inter le peso corporee e le
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fetal distress due to placental insufficiency.
Obst. & G y n e c , 12: 712-726, 1958.
6. G R U E N W A L D , P . , AND M I N H , H . N . : E v a l u a t i o n
of body and organ weights in perinatal
pathology. I I . Weight of body and placenta
in surviving and in autopsied infants. (To
be published.)
7. M E Y E R , A. W.: Fields, graphs, and other d a t a
on fetal growth. Contr. Embryol., 2: 55-68,
1915.
8. P O T T E R , E . L., AND A D A I R , F . L . : F e t a l and
Neonatal D e a t h . Chicago: University of
Chicago Press, 1949.
9. SCAMMON, R. E . , AND C A L K I N S , L. A.: T h e
Sept.
I960
PERINATAL BODY AND OBGAN WEIGHTS
Development and Growth of the External
Dimensions of the Human Body in the Fetal
Period. Minneapolis: University of Minnesota Press, 1929.
10. STOVVENS, D.: Pediatric Pathology. Baltimore: T h e Williams & Wilkins Company,
1959.
253
11. STREETER, G. 1J.: Weight, sitting height, head
size, foot length, and menstrual age of the
human ombrvo. Contr. Embryol., 11: 143170, 1920.
12. TABACK, M . : Birth weight and length of gestation with relation to prematurity. ,1.
A. M. A., 146:S97-901, 1951.