Article Info
Authors
Dr. Awatif A. Alam
Year: 2001
Month: July
Issue: 3
Reference: Alrumikan A.,Dr. Awatif A. Alam .Saudi Epidemiology Bulletin. 2001;8(3):.
This study was conducted to investigate the birth weight pattern and maturity of infants weighing <2500 gms among neonates born during a six month period (January-June 1999), to estimate the prevalence of low birth weight, and to report the documented causes of deaths among the neonates during this time period. The study was conducted at Al-Yamamah Hospital, in Riyadh, after obtaining official approval. A random number of infants and mothers medical files were reviewed for the existence of information and data items needed. Maternal variables were obtained from medical files of mothers who delivered LBW infants within the study period.
A pilot study was conducted to test the applicability of the designed data collection form and the presence of the required information in the records. Low birth weight was defined to include all deliveries below 2500 gm. Perinatal mortality included all infants between 28 weeks of gestation to time of birth, while neonatal mortality included those who died within the first 28 days (4 weeks) of life. For descriptive purposes, birth weight was divided into three categories: Extremely Low Birth Weight (ELBW < 1000 gm), Very Low Birth Weight (VLBW 1001-1500 gm) and Low Birth Weight (LBW 1501-2499 gm).
A total of 8749 infants were delivered between January and June, 1999, of which 504 (5.8%) were below normal weight. Infants with LBW constituted 356 (70.6%), 67 (13.3%) were of VLBW and 81 (16.1%) were ELBW. Male and female infants were close to equal in numbers.
We found a mortality rate for all infants below normal weight of 1 infant per hundred. Among all 504 infants below normal weight, 423 (84%) were alive and 81 (16.1%) were dead. The birth weight stratification of living infants showed that 334 (79%) were of LBW, 56 (13.2%) were VLBW, and 33 (7.8%) were ELBW at birth. Among the dead infants 22 (27.2%) were LBW, 11 (13.6%) were VLBW, and 48 (59.3%) were ELBW. There was no statistically significant difference between sex among dead LBW infants.
Out of 423 live infants, 136 (32.2%) were not referred to NICU. Most infants referred to NICU were of LBW (70.7%). Among those admitted to NICU, 211 (73.5%) lived and 76 (26.5%) died. The overall mortality rate among the LBW infants was 157 (31.2%) irrespective of birth weight subgrouping. Stratification of living infants by birth weight showed that 176 (83.5%) were LBW, 33 (15.6%) were VLBW and 2 (0.9%) were ELBW. Among dead infants 27 (35.5%) were of LBW, 18 (23.7%) were VLBW and 31 (40.8%) were ELBW. The commonest recorded causes of deaths were birth asphyxia, hyaline membrane disease, preterm birth and congenital abnormalities (Table 1).
The gestational age of LBW infants showed that 290 (57.5%) reached 35 weeks or more at the time of delivery, 179 (35.5%) were born between 24-34 weeks and 35 (7.0%) were born before 24 weeks of pregnancy.
Regarding mode of delivery 413 (81.9%) were born by normal vaginal delivery and 91 (18.1c/0) by caesarian section. An attempt was done to find out the time interval between admission of infants to NICU and the outcome (dead or alive), but this could not be achieved.
Editorial note:
The reduction of infant mortality is a major goal of the Saudi government's health plans and is considered as part of the future strategy for health. In most developing countries, approximately half of infant deaths occur during the first month of life.[1]
Low birth weight is of public health importance because of the strong relationship between birth weight and infant mortality and morbidity. Studies using linked birth/infant death files. have reported that infants weighing <2,500 gm at birth are at a considerably increased risk of neonatal mortality, which was found to be 40 times more likely among LBW infants and 200 times greater among very low birth weight infants (VLBW, those weighing < 1,500g at birth) than it is among infants of normal birth weight.[2]
The best available global estimate of the prevalence of LBW was produced by the World Health Organization in the 1980s, and the highest reported rates were from Asia, ranging between 30-40% in the Indian subcontinent, to 5-6% in China and Japan.[3] In West Africa, the LBW rates were 10%-20%, whereas in North Africa the rates were 5%-15%. The ranges of LBW rates were 10%-18% in Central America and 9%-12% in South America. However the lowest LBW rates were reported for North America and Europe, with rates in the range of 4%-8%. In developing countries, most LBW is related to intrauterine growth retardation, whereas in developed countries most LBW is related to preterm delivery and its consequences. [4]
LBW infants are more susceptible to a wide range of conditions such as neurological problems, cerebral palsy and seizure disorders, severe mental retardation, lower respiratory tract infections, hearing disorders, behavioral problems, and complications of neonatal intensive care interventions, and general morbidity.[2]
It is known that the causality of low birth weight is associated with many factors, and it has been established that the birth weight is not only a critical determinant of survival, growth and development, but also a valuable indicator of maternal health. The incidence of premature deliveries is an indication of the general health and reproductive efficiency of a population. Moreover, the rates of survival of LBW infants reflect the standard and efficiency of perinatal care services.[5]
Low birth weight and its close association with neonatal and post neonatal mortality, as well as infant and child morbidity, makes it a focus of attention for public health interventions. The magnitude of the problem of low birth weight, as reflected by its incidence, constitutes a priority of attention from health authorities. The incidence of LBW infants range from 4% in Scandinavia and 2% in England to 17.7% in rural south Africa.5
In this study infants below the normal weight constituted 5.8% of all deliveries and the mortality rate was 1%. Major causes of prenatal deaths reported in this study are similar to causes reported in another hospital in the Kingdom of Saudi Arabia.[6]
The best defense against infant mortality and LBW is early and continuous prenatal care, which is particularly effective among high-risk medical and socio-economic groups.
References
- A joint WHO/UNICEF Maternal care for the reduction of perinatal and neonatal mortality.1986; 5-21.
- Lynne S, James S. From data to action, CDC's public health surveillance for women, infants, and children. LBW and Intrauterine Growth Retardation. CDC Monograph 1990: 158-200.
- WHO, the incidence of Low Birth Weight: an update. Wkly Epidemiol Rec 1984; 59: 205-11.
- Villar J.Belizan JM. The relative contribution of prematurity and growth retardation to LBW in developing and developed societies. Am J Obstet Gynecol 1982; 143: 793-8.
- Olusanya 0, Kaul S. Contribution of LBW and VLBW infants to perinatal mortality: The experience of SA district hospital. SMJ 1993; 14(5): 452-455.
- Wagib B, et al. Neonatal deaths in the Asir region of Saudi Arabia: experience in a referral neonatal ICU. ASM 1997; 17(5): 522-526.
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Table I. Causes of Death among LBW infants
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Condition
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Males
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Females
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Total
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|||
|
No.
|
%
|
No.
|
%
|
No.
|
%
|
|
|
Birth Asphyxia
|
9
|
11.7
|
10
|
12.9
|
19
|
24.6
|
|
Hyaline Membrane Disease
|
10
|
12.9
|
5
|
6.5
|
15
|
19.4
|
|
Preterm Birth
|
9
|
11.7
|
5
|
6.5
|
14
|
18.2
|
|
Congenital Abnormalities
|
6
|
7.8
|
6
|
7.8
|
12
|
15.6
|
|
Intravenous Hemorrhage
|
2
|
1,7
|
5
|
6.5
|
7
|
9.2
|
|
Sepsis
|
4
|
5.1
|
3
|
3.9
|
7
|
9.0
|
|
Necrotizing Enterocolitis
|
1
|
1.3
|
2
|
2.7
|
3
|
4.0
|
|
Total
|
41
|
53.2
|
36
|
46.8
|
77
|
100.0
|