Postnatal Somatic Growth in Infants With Atypical Fetal Growth Patterns Grace E. Holmes, MD; Herbert C. Miller, MD; Khatab Hassanein, PhD;
differentiate patterns of postnatal in 61 fullterm newborns with either normal or atypical somatic fetal growth. At birth, 14 normal babies had average ponderal indices, 14 were \s=b\ We
physical growth
overweight for length (high ponderal index), 18 were underweight for length (low ponderal index), and 15 had short crown-heel lengths for dates and normal ponderal indices. Appropriate statistical analyses determined attained and velocity growth of the four groups during the first postnatal year. Statistically significant
of fetal in
atypical patterns Several diagnosed growth by using
have been newborn infants in this clinic
appropriate anthropométrie measure¬ ments.1 These atypical patterns in¬ cluded infants whose body dimensions were unusually small or large at birth
for their fetal ages, infants with marked disproportion between body length and head size, and infants with unusually small or large accumula¬ tions of soft tissue mass as calculated by means of Rohrer's ponderal index: weight in grams x 100 * body length From the Departments of Pediatrics (Drs Holmes and Miller), Pediatrics and Psychiatry (Dr Lansky), and Biometry (Dr Hassanein), University of Kansas Medical Center College of Health Sciences and Hospital, Kansas City, Kan, and the Department of Psychiatry (Dr Goggin) Texas Tech University Health Sciences Centers, Lubbock, Texas. Reprint requests to Department of Pediatrics, The University of Kansas Medical Center, Rainbow Blvd at 39th, Kansas City, KS 66103 (Dr
Holmes).
Shirley
B.
Lansky, MD; James
marked differences in postnatal were noted between short babies and babies with low ponderal indices. The slow postnatal growth of the short infants appeared to be a continuum of their fetal growth pattern. On the other hand, infants born with low ponderal indices accelerated their weight gains and reversed the malnourished state in which they were born. These findings suggest that there are two distinct types of fetal growth retardation. (Am J Dis Child 131:1078-1083, 1977) and
growth
in centimeters3.2 We are not aware of any detailed studies of postnatal growth in the first year of infants fitting any of these atypical fetal growth patterns. Fisch et al' com¬ pared the growth of extremely obese with the growth of lean neonates and found that at 4 and 7 years of age these children tended to have the same body habitus as at birth. Data on their growth in the first postnatal year were not provided. Previous investigators of undergrown or overgrown fetuses relied almost exclusively on a low or high birth weight in relation to gestational age in diagnosing atypical fetal growth.4'3 The criterion of birth weight for fetal age does not provide information on external body dimen¬ sions or on degrees of leanness or obesity. Calculation of the ponderal index helps to differentiate the fullterm infant who is proportionately
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E.
Goggin, PhD
in body dimensions and normal ponderal index from the thin, fullterm infant who has a normal body length but an abnormally low ponderal index. Likewise, a high birth weight for fetal age does not distin¬ guish the obese infant from the infant who is not obese but who has large body dimensions. The present study was carried out prospectively on fullterm infants in¬ cluding a group with normal fetal growth, an obese group, and two groups with different types of fetal growth retardation. The obese group had ponderal indices above the 97th percentile according to a scale devised by Miller' relating ponderal index distribution to calculated gestational age (Fig 1). The two types of fetal growth retardation in the other two groups have been described previous¬ ly.1 In one type (low ponderal index), ponderal indices are at or below the third percentile for fetal age and body lengths are within normal limits for fetal age. In the second type, crownheel lengths are abnormally short for fetal age (Fig 2), and ponderal indices are within normal limits for gesta¬ tional age. Lower points on Fig 2 constitute the one and a half percen¬ tile of length for fetal age. We have labelled the latter group short-fordates. We are reporting now on the phys¬ ical growth and clinical courses of these four groups during the first 12 postnatal months, because we have
undergrown
has
a
observed statisically significant dif¬ ferences among them. SUBJECTS AND METHODS The 61 fullterm infants in the study were included without regard to race, age, parity or socioeconomic status of mothers, or sex of infants. The infants were born between January 1, 1973, and November 1, 1974; all were born at the University of Kansas Medical Center except for two babies who were born in small hospitals and referred to the medical center in the early neonatal period. Criteria for admission to the study were as follows: The infants were single born and had no obvious congenital malfor¬ mation, intrauterine infection, metabolic disorder, or medical disease and had a calculated and/or estimated gestational age of 38 weeks or more with the exception of three children who were judged to be at 37 weeks gestational age. Gestational age was calculated in terms of completed weeks of gestation from the first day of the mother's last menstrual period. Estimated gestational age was based on physical maturational and neurological signs as described by Lubchenco.1" None of the mothers were diabetic or prediabetic. One of us (H. C. M.) examined and measured all infants within the first 24 hours after birth and diagnosed the pattern of fetal growth present in all infants according to methods previously described.'" The tonic-neck reflex was used during measurement of length to overcome the tendency of neonates to keep their hips and knees flexed. Ponderal indices at birth were calculated using Rohrer's formula. Infants whose crown-heel lengths fell at or below
36 38 WEEKS
Fig 1.—Distribution of ponderal indices by percentile groups in a control group of newborn infants according to their calcu¬ lated gestational age (CGA).1 55 o
54 :
" 53L
l·-
52 : 51 :
5 '49: 48 : 5 47 : o er 46 o
45: 37 39 41 43 GESTATION -wks.
Fig 2.—Newborn crown-heel length in rela¬ tion to gestational age with extremes at the one and a half and ninety-eight and a half percentiles.
half percentile for fetal age considered short for fetal age.'2 Mean ponderal indices, standard deviation, and standard error of all groups are presented in Table 1. Some of the mothers' pregnancies involved factors believed to retard fetal growth, such as cigarette smoking, poor maternal weight gain during pregnancy, preeclampsia, and chronic hypertension. The presence or absence of these growthretarding factors in the mothers' pregnan¬ cies did not affect the selection of infants for the study. The nature of the follow-up clinic was fully explained to the mothers who signed an informed consent-form approved by this institution. Of the original 78 children selected according to the above criteria, 17 patients were lost to follow-up because of moving to another city, follow-up with a private physician, or by the decision not to continue in the study. General procedure at each clinic visit included measuring and weighing of the infant by the pediatrie nursing staff prior to being seen by the pediatricians in the study. Measurements of height and weight were made on a pediatrie table equipped with an integral weighing scale and hori¬ zontal measuring rule. An interval history was taken and a physical examination performed. All children were followed up by the physicians in the Fetal Growth Clinic except for five infants who were followed up through the general pediatrics clinic at the University of Kansas Medical Center according to the general procedure noted above.
the
one
(Fig 2)
and
a
were
RESULTS Mean values for attained growth and velocity growth were calculated at five time-points and four age inter¬ vals from birth through the first 12 postnatal months for the four groups of infants. The time-points, at which successive measurements were made, were not exactly the same for all infants (Table 2). Infants whose mea-
Table 1.—Mean Values of Ponderal Indices at Birth of Four Groups of Infants With Different Growth Patterns Ponderal Index Mean Value 2.61 3.0371 2.137 2.489
Subject Group Normal
14
High ponderal index Low ponderal index
14 18 15
Short-for-dates
Table 2.—Mean
Age
SD .13 .0867
.0839 .1695
SE .04 .0232 .0197 .0438
in Weeks at Four Time-Points and Standard Deviation
Birth
Subject Group
Mean
Normal
14
6.6 6.4
High ponderal index Low ponderal index
14 18
14 18
Short-for-dates Total (N)
15 61
11 57
8.0 9.0
SD 1.9 1.7 1.9 2.2
14 14
18 14 60
Mean 20 15 19 19
SD 1.9
12
3.3 2.7 2.1
12 17
11 52
5t indicates weeks.
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Mean 30
SD 2.0
29 30 29
3.5
13
3.2 2.9
16
54 54
14
53
Mean 55
54
SD 3.0 3.9 2.9 2.1
Table 3.· -Mean Measurements and Standard Deviations at Five Time-Points in the First Postnatal Year for Infants With Four Different Fetal Growth Patterns Birth Mean
Subject Group Body weight, gm High ponderal index Low ponderal index Short-for-dates
Body Length,
SD
Mean
364
3,560 4,230 2,854 2,494
Normal
SD
4,886 5,237 4,737 4,378
500 241 184
Mean
6,811 6,536 6,661 5,899
695 567 846 684
Mean
SD
1,010 1,138
7,908 8,182 7,701 6,676
853
1,003
Mean
SD
SD
9,796 10,431 9,666 8,508
1,184 1,178 1,003 808
1,305 1,043 1,156 801
cm
Normal
51.4
1.3
56.2
2.6
High ponderal index Low ponderal index
51.8 51.1
2.2
56.3
3.1
46.·
0.7
56.9 53.2
2.8 2.7
63.5 61.1 64.6 59.7
Normal
34.6
1.3
35.6
1.2
1.4
33.9 32.5
1.2(17)t
38.2 38.5 38.5 37.7
1.5
High ponderal index Low ponderal index Short-for-datest
1.7
41.7
0.6
40.1
Short-for-dates Head circumference,
*t indicates weeks
as
2.7
67.6 67.4
3.1 2.5
75.4
2.7 3.0 2.6
75.4 77.2
2.6
71.8
3.0 3.1
46.4 46.2 46.0 44.5
2.0 1.8 1.4 1.0
2.9
68.7 63.4
42.0
1.9
43.8
1.8
41.1
1.8
43.8 43.5 42.2
1-7(11),
3.3 3.2
cm
0.8
1.0
1.6
0.8
in Table 2.
jNumber of infants same as in Table 2 with the exception of those tNumber of infants at t, 10, t, 11, t., 7, and t4 12. =
Table 4.—Mean
=
=
in
parentheses.
=
Velocity Growth (Growth Increments Per Week) and Standard Deviations for Weight, Height, and Head Circumference in Four Age Intervals in the First Postnatal Year t*, Mean
Subject Group Body weight, gm/wk Normal
200
High ponderal index Low ponderal index
160 218 208
Short-for-dates Body length, cm/wk Normal High ponderal index Low ponderal index Short-for-dates Head circumference, cm/wk Normal High ponderal index Low ponderal index
Short-for-datest
Mean
SD 59.5 79.5
SD
164 153 197 177
60.9 61.9
145
40.5
63.9
138 162 146
33.8 32.7 25.7
44.8 46.8
.21
.61
.10
.70 .69 .75
.21
.63 .71
.11 .09
.20
66
.15
.54 .45 .59 .56
.06
.09(17)t
.38 .36 .41
.08
.40
.05 .07 .05 .07
.54 .55
Mean
SD
44.7
.71
.10
Mean
SD
114 114
24.2 13.4 20.2 12.9
126
113
.09
.44
.07 .06
.61 .59
.08
.30
.04
.28 .33 .35
.03(11)t .03
.01
.49 .46
.05 .03 .04 .04
.22 .19 .23 .22
.02 .02 .02 .01
st indicates weeks as in Table 2. tNumber of infants same as in Table 2 with exception of those in parentheses. tNumber of infants at t, 10, t, 11, t, - 7, t, =12. =
Table 5.—Statistical Variable
Weight
=
Analyses'3·" Time-Point Birth
for Attained Growth and
Velocity
Growth of Infants With Four Different Fetal Growth Patterns
Attained Growth All groups differ from all others (P
differentiate patterns of postnatal in 61 fullterm newborns with either normal or atypical somatic fetal growth. At birth, 14 normal babies had average ponderal indices, 14 were \s=b\ We
physical growth
overweight for length (high ponderal index), 18 were underweight for length (low ponderal index), and 15 had short crown-heel lengths for dates and normal ponderal indices. Appropriate statistical analyses determined attained and velocity growth of the four groups during the first postnatal year. Statistically significant
of fetal in
atypical patterns Several diagnosed growth by using
have been newborn infants in this clinic
appropriate anthropométrie measure¬ ments.1 These atypical patterns in¬ cluded infants whose body dimensions were unusually small or large at birth
for their fetal ages, infants with marked disproportion between body length and head size, and infants with unusually small or large accumula¬ tions of soft tissue mass as calculated by means of Rohrer's ponderal index: weight in grams x 100 * body length From the Departments of Pediatrics (Drs Holmes and Miller), Pediatrics and Psychiatry (Dr Lansky), and Biometry (Dr Hassanein), University of Kansas Medical Center College of Health Sciences and Hospital, Kansas City, Kan, and the Department of Psychiatry (Dr Goggin) Texas Tech University Health Sciences Centers, Lubbock, Texas. Reprint requests to Department of Pediatrics, The University of Kansas Medical Center, Rainbow Blvd at 39th, Kansas City, KS 66103 (Dr
Holmes).
Shirley
B.
Lansky, MD; James
marked differences in postnatal were noted between short babies and babies with low ponderal indices. The slow postnatal growth of the short infants appeared to be a continuum of their fetal growth pattern. On the other hand, infants born with low ponderal indices accelerated their weight gains and reversed the malnourished state in which they were born. These findings suggest that there are two distinct types of fetal growth retardation. (Am J Dis Child 131:1078-1083, 1977) and
growth
in centimeters3.2 We are not aware of any detailed studies of postnatal growth in the first year of infants fitting any of these atypical fetal growth patterns. Fisch et al' com¬ pared the growth of extremely obese with the growth of lean neonates and found that at 4 and 7 years of age these children tended to have the same body habitus as at birth. Data on their growth in the first postnatal year were not provided. Previous investigators of undergrown or overgrown fetuses relied almost exclusively on a low or high birth weight in relation to gestational age in diagnosing atypical fetal growth.4'3 The criterion of birth weight for fetal age does not provide information on external body dimen¬ sions or on degrees of leanness or obesity. Calculation of the ponderal index helps to differentiate the fullterm infant who is proportionately
Downloaded From: http://archpedi.jamanetwork.com/ by a University of Michigan User on 06/13/2015
E.
Goggin, PhD
in body dimensions and normal ponderal index from the thin, fullterm infant who has a normal body length but an abnormally low ponderal index. Likewise, a high birth weight for fetal age does not distin¬ guish the obese infant from the infant who is not obese but who has large body dimensions. The present study was carried out prospectively on fullterm infants in¬ cluding a group with normal fetal growth, an obese group, and two groups with different types of fetal growth retardation. The obese group had ponderal indices above the 97th percentile according to a scale devised by Miller' relating ponderal index distribution to calculated gestational age (Fig 1). The two types of fetal growth retardation in the other two groups have been described previous¬ ly.1 In one type (low ponderal index), ponderal indices are at or below the third percentile for fetal age and body lengths are within normal limits for fetal age. In the second type, crownheel lengths are abnormally short for fetal age (Fig 2), and ponderal indices are within normal limits for gesta¬ tional age. Lower points on Fig 2 constitute the one and a half percen¬ tile of length for fetal age. We have labelled the latter group short-fordates. We are reporting now on the phys¬ ical growth and clinical courses of these four groups during the first 12 postnatal months, because we have
undergrown
has
a
observed statisically significant dif¬ ferences among them. SUBJECTS AND METHODS The 61 fullterm infants in the study were included without regard to race, age, parity or socioeconomic status of mothers, or sex of infants. The infants were born between January 1, 1973, and November 1, 1974; all were born at the University of Kansas Medical Center except for two babies who were born in small hospitals and referred to the medical center in the early neonatal period. Criteria for admission to the study were as follows: The infants were single born and had no obvious congenital malfor¬ mation, intrauterine infection, metabolic disorder, or medical disease and had a calculated and/or estimated gestational age of 38 weeks or more with the exception of three children who were judged to be at 37 weeks gestational age. Gestational age was calculated in terms of completed weeks of gestation from the first day of the mother's last menstrual period. Estimated gestational age was based on physical maturational and neurological signs as described by Lubchenco.1" None of the mothers were diabetic or prediabetic. One of us (H. C. M.) examined and measured all infants within the first 24 hours after birth and diagnosed the pattern of fetal growth present in all infants according to methods previously described.'" The tonic-neck reflex was used during measurement of length to overcome the tendency of neonates to keep their hips and knees flexed. Ponderal indices at birth were calculated using Rohrer's formula. Infants whose crown-heel lengths fell at or below
36 38 WEEKS
Fig 1.—Distribution of ponderal indices by percentile groups in a control group of newborn infants according to their calcu¬ lated gestational age (CGA).1 55 o
54 :
" 53L
l·-
52 : 51 :
5 '49: 48 : 5 47 : o er 46 o
45: 37 39 41 43 GESTATION -wks.
Fig 2.—Newborn crown-heel length in rela¬ tion to gestational age with extremes at the one and a half and ninety-eight and a half percentiles.
half percentile for fetal age considered short for fetal age.'2 Mean ponderal indices, standard deviation, and standard error of all groups are presented in Table 1. Some of the mothers' pregnancies involved factors believed to retard fetal growth, such as cigarette smoking, poor maternal weight gain during pregnancy, preeclampsia, and chronic hypertension. The presence or absence of these growthretarding factors in the mothers' pregnan¬ cies did not affect the selection of infants for the study. The nature of the follow-up clinic was fully explained to the mothers who signed an informed consent-form approved by this institution. Of the original 78 children selected according to the above criteria, 17 patients were lost to follow-up because of moving to another city, follow-up with a private physician, or by the decision not to continue in the study. General procedure at each clinic visit included measuring and weighing of the infant by the pediatrie nursing staff prior to being seen by the pediatricians in the study. Measurements of height and weight were made on a pediatrie table equipped with an integral weighing scale and hori¬ zontal measuring rule. An interval history was taken and a physical examination performed. All children were followed up by the physicians in the Fetal Growth Clinic except for five infants who were followed up through the general pediatrics clinic at the University of Kansas Medical Center according to the general procedure noted above.
the
one
(Fig 2)
and
a
were
RESULTS Mean values for attained growth and velocity growth were calculated at five time-points and four age inter¬ vals from birth through the first 12 postnatal months for the four groups of infants. The time-points, at which successive measurements were made, were not exactly the same for all infants (Table 2). Infants whose mea-
Table 1.—Mean Values of Ponderal Indices at Birth of Four Groups of Infants With Different Growth Patterns Ponderal Index Mean Value 2.61 3.0371 2.137 2.489
Subject Group Normal
14
High ponderal index Low ponderal index
14 18 15
Short-for-dates
Table 2.—Mean
Age
SD .13 .0867
.0839 .1695
SE .04 .0232 .0197 .0438
in Weeks at Four Time-Points and Standard Deviation
Birth
Subject Group
Mean
Normal
14
6.6 6.4
High ponderal index Low ponderal index
14 18
14 18
Short-for-dates Total (N)
15 61
11 57
8.0 9.0
SD 1.9 1.7 1.9 2.2
14 14
18 14 60
Mean 20 15 19 19
SD 1.9
12
3.3 2.7 2.1
12 17
11 52
5t indicates weeks.
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Mean 30
SD 2.0
29 30 29
3.5
13
3.2 2.9
16
54 54
14
53
Mean 55
54
SD 3.0 3.9 2.9 2.1
Table 3.· -Mean Measurements and Standard Deviations at Five Time-Points in the First Postnatal Year for Infants With Four Different Fetal Growth Patterns Birth Mean
Subject Group Body weight, gm High ponderal index Low ponderal index Short-for-dates
Body Length,
SD
Mean
364
3,560 4,230 2,854 2,494
Normal
SD
4,886 5,237 4,737 4,378
500 241 184
Mean
6,811 6,536 6,661 5,899
695 567 846 684
Mean
SD
1,010 1,138
7,908 8,182 7,701 6,676
853
1,003
Mean
SD
SD
9,796 10,431 9,666 8,508
1,184 1,178 1,003 808
1,305 1,043 1,156 801
cm
Normal
51.4
1.3
56.2
2.6
High ponderal index Low ponderal index
51.8 51.1
2.2
56.3
3.1
46.·
0.7
56.9 53.2
2.8 2.7
63.5 61.1 64.6 59.7
Normal
34.6
1.3
35.6
1.2
1.4
33.9 32.5
1.2(17)t
38.2 38.5 38.5 37.7
1.5
High ponderal index Low ponderal index Short-for-datest
1.7
41.7
0.6
40.1
Short-for-dates Head circumference,
*t indicates weeks
as
2.7
67.6 67.4
3.1 2.5
75.4
2.7 3.0 2.6
75.4 77.2
2.6
71.8
3.0 3.1
46.4 46.2 46.0 44.5
2.0 1.8 1.4 1.0
2.9
68.7 63.4
42.0
1.9
43.8
1.8
41.1
1.8
43.8 43.5 42.2
1-7(11),
3.3 3.2
cm
0.8
1.0
1.6
0.8
in Table 2.
jNumber of infants same as in Table 2 with the exception of those tNumber of infants at t, 10, t, 11, t., 7, and t4 12. =
Table 4.—Mean
=
=
in
parentheses.
=
Velocity Growth (Growth Increments Per Week) and Standard Deviations for Weight, Height, and Head Circumference in Four Age Intervals in the First Postnatal Year t*, Mean
Subject Group Body weight, gm/wk Normal
200
High ponderal index Low ponderal index
160 218 208
Short-for-dates Body length, cm/wk Normal High ponderal index Low ponderal index Short-for-dates Head circumference, cm/wk Normal High ponderal index Low ponderal index
Short-for-datest
Mean
SD 59.5 79.5
SD
164 153 197 177
60.9 61.9
145
40.5
63.9
138 162 146
33.8 32.7 25.7
44.8 46.8
.21
.61
.10
.70 .69 .75
.21
.63 .71
.11 .09
.20
66
.15
.54 .45 .59 .56
.06
.09(17)t
.38 .36 .41
.08
.40
.05 .07 .05 .07
.54 .55
Mean
SD
44.7
.71
.10
Mean
SD
114 114
24.2 13.4 20.2 12.9
126
113
.09
.44
.07 .06
.61 .59
.08
.30
.04
.28 .33 .35
.03(11)t .03
.01
.49 .46
.05 .03 .04 .04
.22 .19 .23 .22
.02 .02 .02 .01
st indicates weeks as in Table 2. tNumber of infants same as in Table 2 with exception of those in parentheses. tNumber of infants at t, 10, t, 11, t, - 7, t, =12. =
Table 5.—Statistical Variable
Weight
=
Analyses'3·" Time-Point Birth
for Attained Growth and
Velocity
Growth of Infants With Four Different Fetal Growth Patterns
Attained Growth All groups differ from all others (P
