Risk Factors for Low Birth Weight among Neonates Delivered in Public Health Facilities in Adama Town, Oromia Regional State, Ethiopia

Background: Low birth weight is the major predictor of prenatal mortality and morbidity worldwide. It has been defined by the World Health Organization as weight at birth of less than 2,500 grams irrespective of their gestational age. Rate of low birth weight is still high in developing countries like Ethiopia particularly Oromia regional state where adequate primary health care services for maternal and child health are not universally available to all the populations. It is therefore imperative to identify risk factors for low birth weight in various communities in order to come up with feasible intervention strategies to minimize the problem. Methods : Facility based case-control study design was conducted from June-1/2017 to April-30/2018 on 318 mothers with singleton and full term neonates (108 case to 210 control). Semi structured interviewer administered and pretested questionnaire was used by trained data collectors working in delivery ward. The data were entered and analyzed by using statistical software. Descriptive and bivariate analysis was done. Result: The mean maternal age of all study participants was 26.7 years with [SD of 4.8] with mean age for mothers of cases was 25.5 years and for controls was 27.4 years. In bivariate analysis residency being rural (AOR= 1.95 with 95% CI (1.0-3.48), parity ≥2 (AOR= 3.45 (1.89-6.32), number of antenatal care attendance ˂4 visits (AOR= 0.40(0.218-0.73)), birth interval ˂24 moths (AOR= 2.68 (1.45-4.94), history of hypertension (AOR= 0.39(0.18-0.87) and maternal MUAC ˂21cm (AOR=0.38 (0.159-0.91) were found to be statistically significant. Conclusions: Variables that were found to have a statically significant relationship with low birth weight were residency being rural, occupation, parity ≥2 & birth interval ≤24months, number of antenatal care attendance ˂4 visits, history of hypertension and maternal MUAC ˂21cm were found to be statistically significant.


Background
Low birth weight (LBW) has been defined by the World Health Organization(WHO) as weight at birth of less than 2,500 grams irrespective of their age [1].A baby's low weight at birth is either the result of preterm

Cases
• All full term newborns with weight less than 2500 grams in one of the selected public health facilities of Adama town.

Controls
• Two full term normal weight babies born next to newborns of LBW Sample size was determined by using statistical software (Epi-Info7) after considering Parity, maternal age of ≤ 20, previous history of LBW and maternal education from previous studies [16].Accordingly, 103 cases and 206 controls a total sample size of 309 were included.After adding 10% non-response rate the final sample size was 114 cases and 227 a total 341 will participate in the study.

Data Collection
Data were collected through face-to-face interview and medical record reviews of newborns; after informed verbal consent was take from each mother.Weight of the newborns was taken by the assigned midwife as data collector in the delivery room of the health facilities within the first one hour following delivery.Pre-pregnancy weight of the mother was taken from the antenatal follow up record and height of the mother was measured by using height meter fixed to weight measuring scale.The Measurement of Upper Arm Circumference (MUAC) of the mother was taken from the mother's left arm while the mother is sitting or standing position by MUAC measuring tapes.

Data Analysis
Data were coded and double entered into computer using Epi-Info Version 7 and was exported to SPSS version 21 statistical software for analysis.Descriptive analysis was used to explore the characteristics of women participated in the study.Before analysis the fulfillments of assumption for logistic regression was checked.Bivariate binary logistic regression analysis was applied to assess the crude relationship between independent variables and outcome variable (LBW).At this level the candidate variables for multivariate analysis was selected at P-value < 0.25 significance level.Multivariate binary logistic regression was applied to estimate the adjusted effects of independent variables on outcome variable (LBW) by using backward stepwise method.Odds ratio (OR) was used to estimate the magnitude of association between independent and outcome variable and 95% CI was used to assess the statistical significance of association between independent variables and LBW.

Socio-demographic characteristics
About 318 babies (108 were low birth weight babies and birth or due to restricted fetal growth [2].Pregnancy is a critical period of physiological change for both the mother and the fetus.Fetal growth is largely dictated by the availability of nutrients in maternal circulation and the ability of these nutrients to be transported into fetal circulation via the placenta [3].These factors may relate to the infant, the mother, or the physical environment and play an important role in determining the birth weight and the future health of the infant [4,5].The majority of LBW in developing countries is due to intra uterine growth retardation (IUGR) [6].Causes of IUGR are most of the time focus on the foetus, the placenta and the mother or combinations of all three.Factors that prevent normal circulation across the placenta cause poor nutrient and oxygen supply to the foetus, restricting growth [7].These factors may include maternal under nutrition, anaemia, and acute or chronic infections (such as malaria, sexually transmitted diseases and urinary tract infections) [8].Obstetric history of the mother like primiparity and multiple gestation and foetal genetic or chromosomal anomalies also associated with IUGR [9].Mother's habit like Cigarette smoking, alcohol and drug use may also restrict foetal growth [10][11][12].In developed countries the epidemiology of low birthweight has been extensively studied, in less developed countries reliable data on low birthweight remain limited because of high proportion home delivery.But some studies showed that the levels of low birth weight in developing countries remain unacceptably high.According to the report of a joint study from United Nations International Children's Emergency Fund (UNICEF) and the WHO, which investigated global, regional and country-specific LBW; the level of low birth weight in developing countries is (16.5 %) more than double the level in developed regions (7%).Low birthweight levels in Africa is estimated 14 and in sub-Saharan Africa are around 13 per cent to 15 per cent, with little variation across the region as a whole [13].In Ethiopia, the incidence of low birth weight babies has increased from 8 percent in 2000 to 14 percent in 2005 [14].Based on the 2011 Ethiopian demography and health survey, after 5 years the prevalence decreased by 3 % and in 2011 the proportion of low birth weight in Oromia region was 28 % [15].Identifying maternal factors that are modifiable among this group of women is an important contribution to the of child health.

Study setting & design
A facility-based case-control study design was conducted from June-1/2017 to April-30/2018 to assess risk factors of low birth weight among Neonates born in selected public health facilities in Adama town.The study population were pregnant women who gave birth in sampled public health facilities in Adama town.The ratio of sex among the cases the male to female ratio was 1.25:1 and among controls the male to female ratio were 1.6:1.(Table 1).

Factors Associated with Low Birth Weight among Neonates Born in Public Health facilities in Adama Town
Bivariate analysis was done by enter method for sociodemographic factors, reproductive history, maternal life style and anthropometric measurements of the mother with dependent variable.Variables which were significant in bivariate analysis were put in to multiple logistic regression by backward stepwise method and the final factor significantly influencing occurrence of LBW were residency, occupation, parity, birth interval, ANC visit history of Hypertension, maternal MUAC and weight gain during pregnancy remain to be statistically significantly associated with the low birth weight of neonates (Table 2).
Mother with residency being rural were almost twice risk of having low bith weight than urban (AOR=1.95with 95% CI [1.0-3.48]).Occupation of the mother was assessed by categorizing in to income owned and not income owned in cash; mothers with no income owned had 2.5 times more higher risk of having LBW neonate than comparable groups AOR=2.47 with CI (1.47-4.16).Regarding obstetric history of the mothers, those who have two or more live births were three time higher risk of having low birth weight neonate than primi parus (AOR=3.45with CI [1.89-6.32]).Compared to mothers with birth interval of ˃24 months, mothers with birth interval ˂ 24 month had three times higher more likely to have LBW.On the other hand previous history of abortion, gestational age of first antenatal care (ANC) & history of anemia during pregnancy were not found to have association with LBW delivery in this study (Table 3).
In this study maternal lifestyle or habits like coffee intake, alcohol intake & khat chewing didn't show significant association with the dependent variable.Logistic regression analysis of maternal anthropometric measurement like MUAC and weight gain during pregnancy showed significant association with occurrence LBW.Depending on UNICEF cut off point for detecting malnutrition in adults; maternal MUAC was classified in to two categories.Mothers who had MUAC ≤ 21cm have 30% more likely to have LBW than their comparable groups (AOR=0.3 with 95% CI (0.159-0.91)) ( Table-4).

Discussion
In the present study the relationships between LBW, residency, occupation, parity & birth interval, number of antenatal care attendance, history of hypertension and maternal anthropometry were found to be statistically significant.In this study, residency being rural has twice higher risk of giving LBW than mothers in urban dwellers.This finding is consistent with other studies in the country [17,18].The association of parity of women with low-birth-   consistent with results from other studies in different parts of the world (16,20,(32)(33)(34).Inter pregnancy interival is the time for the mother to recover from nutritional depletion as a result of fetal demand during previous pregnancy and lactation after birth.Short inter pregnancy interival may worsen the mother's nutritional status and adequate time is needed to recover and prepare for the next pregnancy.

Conclusions
This study was designed to investigate the maternal risk factors that contributed to the risk of having low birth weight in Adama Town Public Health Facilities.Variables that were found to have a statically significant relationship with low birth weight were residency being rural, occupation, parity ≥2 & birth interval ≤24months, number of antenatal care attendance ˂4 visits, history of hypertension and maternal MUAC ˂21cm were found to be statistically significant.Brief and detailed counselling on ANC attendance should be emphasized for early initiation of ANC visits in order to tackle obstetric related maternal risk factors for LBW and develop an effective prevention strategy to reduce low birth weight.
Further studies are also needed to identify why some pregnant women do not attend ANC on early gestational age which might be the base for early detection and intervention of risk factors for LBW .

Table 1 :
Socio demographic characteristics of mothers of the study participants in Adama town Public Health Facilities, Oromia Regional state, Ethiopia, 2017.

Table 2 :
Logistic Regression Analysis of Factors Affecting Low Birth Weight Neonates in Adama Town Public Health Facilities, East ShoaZone, Oromia Regional State 2017.

Table 3 :
Association of maternal characteristics with LBW in Adama Town Public Health Facilities, Oromia Regional state, Ethiopia, 2017.

Table 4 :
Association of Maternal Lifestyle and Anthropometric Measurement with LBW in Adama Town Public Health Facilities, Oromia Regional State, Ethiopia, 2017 Citation: Nigusse Obse Nebi, Tolossa Eticha Chaka, Tilaye Workineh Abebe, Ephrem Mannekulih M. Risk Factors for Low Birth Weight among Neonates Delivered in Public Health Facilities in Adama Town, Oromia Regional State, Ethiopia Journal of Biotechnology and Biomedicine 6 (2023): 401-408.