 |
|
Brief Reports Indian Pediatrics 2000;37: 872-876 |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Socioeconomic and Demographic Factors Associated with Birth Weight: A Community Based Study in Kerala |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
From the Achutha Menon Center for Health Science Studies, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram. Reprint requests: Dr. K.R. Thankappan, Associate Professor, Achutha Menon Center for Health Science Studies, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram 695 011, India. E-mail: [email protected]
Kerala State is noted for its high health achievements at low cost; most health indices are comparable to those of developed countries(2). However, Kerala has been reported to have a high proportion of LBW compared to developed countries; the National Family Health Survey of India (1992) reported that 18.2% of newborns in Kerala have a LBW(3). The present investigation was designed to determine the proportion of LBW infants in a community based sample in Kerala and to evaluate potential socioeconomic and demographic correlates of the condition.
Our sampling frame consisted of non-coastal village Panchayaths of Thiruvanan-thapuram district in Kerala state. We chose this district because of its well functional Integrated Child Development Services (ICDS) Program, a feature that ensures adequacy of birth records of infants born in the district and facilitates tracking of the mothers(4). Kadakampally village Panchayath was selected for the present investigation. We performed a cross sectional survey of all infants born in Kadakampally Panchayath during the reference period from 1 January, 1997 to 31 December, 1997. Based on its population size of 24540(5), and the state-wide birth rate of 17/1000, we estimated that a sample size of about 400 live births would yield reliable estimates of the frequency of LBW and would be adequate to assess the socioeconomic and demographic factors associated with LBW. We contacted the ICDS centers in Kadakampally Panchayath and collected the birth records of all infants born in 1997 and the addresses of their mothers. There were 294 mothers who delivered 301 infants during the reference period. After exclusion of 21 infants (14 twins, 7 others without birth records), 280 infants and their mothers constituted our study sample. Mothers of these 280 infants were contacted by one of the investigators (TR) and informa-tion collected on socioeconomic factors, demographic characteristics, and medical history using a pre tested questionnaire. We collected information regarding the education of the mother and the father of the infant, family income, housing conditions like roof of the house, wall of the house, floor of the house and floor area of the house. Socio-economic status (SES) of the households was assessed as a composite index incorporating several of these variables. Briefly, a weighted score (range 7 to 21, median 13), based on the variables listed above was used to categorize our sample into two groups Low SES below the median and high SES above the median score. Previous studies in Kerala have validated such an approach for determining socioeconomic status of households in Kerala(6). The questionnaire also sought the following additional demo-graphic and medical information: maternal age at delivery, occupation of mother, religion, place of delivery, antenatal care including history of sonographic examination during pregnancy, birth order, gestational age and sex of the baby. Bivariate and multivariate analyses were done on 265 term babies only while other descriptive data analysis was done on all babies (n = 280). Chi square tests and chi square trend test was used to assess bivariate associations of select predictor variables with low birth weight. We constructed multiple logistic regression models to assess the association of SES with the occurrence of a LBW infant adjusting for other predictor variables. A p value <0.05 was considered as statistically significant.
All but two women had institutional deliveries. Most deliveries took place in government hospitals. Seventy five per cent of the mothers had more than ten antenatal visits to the doctors, 21% had between 5 to 10 visits, while the remainder had between 3 to 5 visits. Seventy four per cent of mothers underwent prenatal sonographic examination. About 4% of the women were less than 20 years of age, and another 4% were over the age of 35 years. Fifty infants had a LBW (17.9%; 95% CI = 13.4-22.4%). Among term babies (gestational age >37 weeks, n = 265), 16.2% (95% CI = 11.7-20.7) had a LBW. Among 15 pre-term babies 54% had a LBW. In the bivariate analysis SES of family was found to be significantly associated with LBW (Table I). In multivariate logistic regression model also maternal SES emerged as the principal determinant of LBW. A low SES was associated with a 3.5 fold (95% CI = 1.6-7.6) elevated risk of LBW in the baby compared to a high SES of the mother. There was no association found between LBW and other variables included in the multivariable analyses (Table II ). Table I - Bivariate Associations of Birth-Weight and Selected Characteristics
'Y' Yates corrected; *Trend test;.: # Fishers exact test;@ Grouping at the median cut off point. Figures in parentheses indicate percentages. Table II - Multiple Logistic Regression of Low Birth Weight (Dependent Variable) on Select Predictor Variables
Variables considered but not significant: age at delivery, antenatal check-up, birth order, height, sex, religion. SES = socio-economic status, b = regression coefficient, SE = standard error, CI = confidence interval.
Our estimate of 17.9% LBW babies in a randomly selected community-based sample in Thiruvananthapuram district in Kerala is consistent with prior reports from Kerala. Our investigation suggests that a low maternal socioeconomic status was the principal determi-nant of a LBW. We did not find an association of LBW with level of maternal education, perhaps because most women were literate. There was also no association between birth order and LBW. We did not detect any association of gender of the infant and LBW, contrary to some other reports(7). There was no association between frequency of antenatal visits and LBW probably because all mothers had a least 3 visits. The association of a low SES with LBW has been reported previously(8,9). Such an association may be related to several potential mechanisms. A poor maternal nutritional intake during pregnancy (more likely in the low SES groups and related to certain cultural practices) is an important mechanism(10). Unfortunately, we did not obtain information regarding maternal nutrition during pregnancy in the present study to investigate this mechanism further. A striking observation in our study was the high prevalence of LBW babies in the face of a very high frequency of antenatal examinations and prenatal ultrasound examinations. These findings suggest that perhaps maternal weight gain during pregnancy and fetal growth are inadequately monitored. It is also possible that practitioners ‘accept’ prevalent birth weight of infants and current maternal weight gain in pregnancy as the ‘norm’ for a ‘developing’ country and do not intervene. It is also possible that practitioners consider it futile to provide advice regarding additional nutritional supple-mentation to women with inadequate weight gain in pregnancy, given their awareness that women with a low SES are likely to lack the economic means to comply with such advice. Our results also call into question the adequacy of performance of the Anganwadi workers in ensuring maternal nutritional supplementation during pregnancy. Since Kerala is a poor state with a per capita income of US $ 275(2), economic development would be the key factor for reducing the prevalence of LBW babies in the state. Improving the quality of ICDS program, antenatal care, and providing supplementary feeding for the pregnant women of low SES may be a short-term option. We did not check the accuracy of the birth weight record in different institutions which is a limitation of this study. We believe that this factor may not significantly affect our study findings because we used only logistic models in which the dependent variable is dichotomous (presence of low versus normal birth weight). Contributors: TR proposed the idea and conducted the actual cross-sectional survey. KRT and RSV assisted in designing the research protocol and preparing the question-naire; they supervised the data collection and the data analysis. PSS assisted in formulating the sampling strategy, preparing the compu-terized data entry form, and did the statistical data anlaysis. All investigators contributed to the writing of the paper. Funding: None.
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Key Messages |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
|
