Department of Pediatrics and Obstetrics and Gynaeowgy, Lady Hardinge. Medical College and Associated Hospitals, New Delhi. Midarm to head circumference ...
Indian J Pediatr 1988 : 55 : 283-286
A simple method of screening for intrauterine growth retardation at birth Sudarshan Kumari, Sharda Jain, Gulshan Rai Sethi, Mahesh Yadav, Arvind Saili and Umesh Bihari Lal
Department of Pediatrics and Obstetrics and Gynaeowgy, Lady Hardinge Medical College and Associated Hospitals, New Delhi Midarm to head circumference ratio was evalaated in 233 term infants for identification o f intrauterine growth retardation(IUGR) at birth. A ratio of O"233-t-0.014 could identify all babies with severe IUGR, while alt but two babies with mild l UGR had this ratio less than O"280. The observation suggest that this method can be utilised lbr easy diagnosis o! I UGR even by paramedical workers at community level, and is independent Ol ethnic groups or intrauterine growth curves.
Key words : Intrauterine growth; Midarm/head ratio In third world countries, 25 to 40~o babies have low birth-weight ( < 2 . 5 kg) and two third ofthem are growth retarded. It has been shown that growth retarded babies differ in etiology, neonatal morbidity, mortality and later development from term appropriately grown infants. I-3 Identification of intrauterine growth retardation is essential in care of newborn babies if problems of hypothermia, hypoglycemia, hypocalcemia and polycythemia are to be prevented. 4 As majority of births continue to occur at home level where measuring weight is not an easy task in developing countries, midarm circumference has been identified as a simple and accurate parameter to detect lowbirth weight babies.S, 6 The present study highlights further bsefulness of meast,,ring tap to determine
Reprint requests : Dr. Sudarshan Kumari, 23B16 P-2, New Rohtak Road, New Delhi 110003.
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intrauterine growth retardation by using midarm to head circumference ratio at birth in term infants.
Material and Methods Two hundred and thirty three newborn infants admitted to neonatal nursery comprised the study population, Gestational age was exactly known in all cases and corresponded with the clinical assessment of gestation by Dubowitz's method. Birth weight was recorded by standard techniqtle with accuracy of 20 gin. Midarm eircumterence was measured with a fibre glass tap at mid point of distance between olecranon process of ulna and acromion on left upper arm. Head circumference was taken as the largest occipito frontal circumference of skuU. All measurements was recorded within 24 hours of birth. Position of individtml babies was plotted on intrauterine growth curve of
284 THE INDIAN JOURNAL OF PEDIATRICS N o r t h Indian babies by Ghosh et al. 7 All infants below 1 SD o f mean birth weight for gestation were classified as having mid intrauterine growth retardation (IUGR), below 2 SD as severe intratuerine growth retardation (S1UGR or SFD), > 2 SD as large for gestational age ( L f D ) and below 37wk gestational preterm. Means and standard deviation was determined for different categories o f babies or mioarm circumference and its ratio to head circumference and statistical significance determined by student 't' test. Results and Discussion
Among 233 infants included in this study, mean 4-1 SD o f midarm circumference was 9" 714-1- 32 cms. Mean4-1 SD of arm circumference o f babies according to their position in intrauterine growth curves has been given in Table I. It is to be noted that though mean midarm circum-
Vol. 55, No, 2 ference was significantly different between babies who had mild to severe intrauterine growth retardation ( I U G R for S I U G R ) or large for date babies ( L F D ) when- c o m pared to average for getational age babies (AGA) there was much overlap in different groups for individual values when q-1 S D w a s taken as normal variation. Thus arm circumference alone is ineffective as a single parameter t o diagnose growth retardation at birth. However, neonatal birth weight can readily be estimated by midarm circumferene alone, taking into account 4- ! SD, it was (8.34-0"7) 9.0 cm and ( 7 . 4 4 - 0 . 6 ) 8"0 cm respectively for babies weighing < 2 " 5 and < 2 . 0 kg at birth in the present study. Brenda et al 5 recorded midarm circumference < 9 . 0 cm, head circumference < 32"0 cm and chest circumference o f < 3 0 . 0 cm as indicator o f low birth weight ( < 2 . 5 kg). An earlier study from Delhi, 6 recorded < 8" 7 cm and < 7 . 5 cm arm circumference respectively
Table I. Mean -t- 1 SD of midarm circumference and its ratio to head circumference according to intrauterine growth.
No.
Midarm circumference (cm)
Midarm/head circumference ratio
Mean 4- 1 SD
Total Mild IUGR* S1UGR** AGA LFD
233 30 20 170 13
9.714-1 932 8.544-0.62 7. 07=[=0.42 9"96 4-0.91 12.01 4-0- 62
0.289 4-0"028 0. 264-/-0.018 0.233 4-0.014 0.2944- 0.023 0.335•
*For midarm circumference, differences were statistically significant from mean value of all babies at < 0.00I level.
**For MAC/Head circumference ratio, significant differences between total mean ratio and mild and severe IUGR infants. Mild IUGR : Intrauterine growth retardation 1 to --2 SD SIUGR : Severe intrauterine growth retardation --2 SD birth weight AGA : Appropriate for gestation ~ 1 SD LFD : Birth weight > 2 SD
KUMARI ET AL : SCREENING FOR IUGR AT BIRYH
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to represent birth weight < 2 . 5 and < 2 . 0 kg respectively, while workers from National Institute o f Nutrition, Hyderabad did not find arm circumference at birth as a useful indicator of neonatal birth weight. 8 Midarm circumference and its ratio to head circumference has been evaluated as an indicator of protein energy malnutrition in children between 3 months to five years o f 8go and is useful at the community level. 8 However, there are very few reports of its use in diagnosing intrauterine growth retardation at birth. 9 In the present study, we noted that this ratio was significantly lower in growth retarded babies than in term appropriately grown babies. All babies with S I U G R ha0 this value with +1 SD of mean 0.2334-0.04. In case o f I U G R all but two babies could be identified by using this ratio. Sensitivity, specificity, positive and negative predictive value in identifying I U G R and S I U G R by application of midarm/head ratio o f cut off points < 0 . 2 8 0 and < 0- 250 respectively revealed the ratio to be a useful predictor of I U G R and S I U G R (Mean 4- 1 SD value) as depicted in Table I I. Meadow's et al 9
have also recorded accurate identification of intrauterine growth retrdation at birth by using the ratio of midarm to head circumference in United Kingdom. They even suggested that this ratio could be used in different ethnic group neonates who may vary in their intrauterine growth. Before applying to findings o f present study to any other population it would be wise to conduct a pilot test in small series of neonates. To conclude, the findings of the present study indicate midarm to head circumference ratio as a simple parameter, independent of ethnic group and intrauterine growth carves to identify term babies with fi~trat~terine growth retardation. Hence use o f a measuring tape alone can not only identify low birth weight babies, but is also valuable in identifying those with growth retardation. We feel that this method has a useful potential in community surveys by paramedical personnel, epidemiological studies and in management of growth retarded babies at community level. Whether findings of the present study also can be applied to diagnose growth retardation in preterm babies needs further evaluation.
Table II. Predictive value of arm/head circumference ratio in diagnosis of IU'GR and SIUGR babies
References
Midarmlhead circumference ratio