Socio-demographic and economic characteristics
The study included 384 controls and 96 cases. Table-2 summarizes and compares the socio-demographic characteristics of cases and controls. It is observed that the two groups were significantly different in many socio-demographic variables and socio-economic status. The mean (± SD) age of the mothers of controls and cases were 24.7 (± 4.9) and 25.1 (± 6.1) respectivelly but the difference was not significant (p=0.369). About 65.0% of mothers who have NBW babies and 35.0 % of mothers with LBW baby live in the urban area (P=0.001). More than half of mothers of respondent for controls and cases were Sidama in ethnicity 73.1% and 66.7% respectively (p=0.041). More than two-third of mother of cases 71.9% and more than three-fourth of mothers of controls 94.5% were married (p=0.001). About 22% of mothers in the control group and 38.5% of mothers from the case group did not have formal education (P=0.006). The majority of the mothers of the control group 70.0% and mothers of case group 63.5% were protestant in religion (p=0.032).Concerning monthly income more than one fourth of mothers of NBW babies (28.9%) and one fourth of mothers of LBW (25.0%) earning between 1501-2500 Ethiopian Birr (P=0.012) (Table 1)
Table 1
Distribution of mothers by socio demographic characteristics in Sidama Zone selected government hospital, Ethiopia, June 2018.
Variables
|
LBW
|
NBW
|
x2P-Value
|
Frequency %
|
Frequency %
|
Age (Years)
|
|
|
|
|
|
<20
|
15
|
15.6
|
36
|
9.4
|
0.369
|
20-35
|
71
|
74.0
|
326
|
84.9
|
|
>35
|
10
|
10.4
|
22
|
5.7
|
Residence
|
|
|
|
|
Urban
|
34
|
35.4
|
252
|
65.6
|
0.001*
|
Rural
|
62
|
64.6
|
132
|
34.4
|
|
Ethnicity
|
|
|
|
|
Sidama
|
64
|
66.7
|
281
|
73.2
|
0.041*
|
Gurage
|
12
|
12.5
|
39
|
10.2
|
|
Amhara
|
10
|
10.4
|
35
|
9.1
|
Wollayta
|
10
|
10.4
|
28
|
7.5
|
Marital status
|
|
|
|
|
Married
|
69
|
71.9
|
363
|
94.5
|
0.001*
|
Divorced
|
27
|
28.1
|
21
|
5.5
|
|
Occupations
|
|
|
|
|
Housewife
|
46
|
47.9
|
198
|
51.6
|
|
Merchant
|
15
|
15.6
|
60
|
15.6
|
0.004*
|
NGO
|
12
|
12.5
|
12
|
3.1
|
Student
|
12
|
12.5
|
49
|
12.8
|
Gov’t employee
|
11
|
11.5
|
65
|
16.9
|
Income
|
|
|
|
|
|
≤1500
|
43
|
44.8
|
101
|
26.3
|
0.012*
|
1501-2500
|
24
|
25.0
|
111
|
28.9
|
2501-3500
|
16
|
16.7
|
88
|
22.9
|
>3501
|
13
|
13.3
|
84
|
21.9
|
Maternal obstetric and health care seeking characteristics
About 43.5% of mothers who have NBW babies and 27.1% of mothers who have LBW offspring had the recommended four and more ANC follow-ups during the index pregnancy (P=0.001). Almost 46.9 % of mothers with LBW and 17.0% mothers with NBW babies have gestational age of less than 37 weeks (P=0.001). Nearly half of mothers who given LBW (53.1%) and NBW infants (48.7%) were multiparous (p=.0.003) (Table 2).
Table 2
Distribution of mothers by obstetric and health care seeking characteristics in Sidama Zone selected government hospital, Ethiopia
Variables
|
LBW
|
NBW
|
x2P Value
|
Frequency
|
%
|
Frequency
|
%
|
ANC visit
|
|
|
|
|
|
One Visits
|
23
|
24.0
|
13
|
3.4
|
0.001*
|
Two visits
|
19
|
19.8
|
62
|
16.1
|
Three Visits
|
28
|
29.2
|
142
|
37.0
|
>=4 visits
|
26
|
27.1
|
167
|
43.5
|
Gestational week at delivery
|
|
|
|
|
|
≥37
|
51
|
53.1
|
319
|
83.0
|
0.001*
|
<37
|
45
|
46.9
|
65
|
17.0
|
History of pregnancy complication
|
|
|
|
|
|
No
|
18
|
18.8
|
64
|
16.7
|
0.002*
|
Yes
|
78
|
81.2
|
30
|
83.3
|
Parity
|
|
|
|
|
|
Primi-Para
|
35
|
34.5
|
166
|
43.3
|
0.003*
|
Multi-Para
|
51
|
53.1
|
187
|
48.7
|
Grand multi-Para
|
10
|
10.4
|
31
|
8.0
|
*significant association at P- value of 0.05.
|
Maternal nutritional factors
Height and MUAC of the mothers were measured. Additionally, during pregnancy nutritional advice, iron intake level and hemoglobin level were assessed. Around 95.3% of mothers who have NBW infant and 84.5% of mothers who have LBW infants have maternal height of greater than or equal to145cm (P=0.002). Almost 67.7% of mothers who have LBW babies and 61.5% of mothers who have NBW babies have MUAC of less than 23cm which is indicative of wasting (P=0.213). More than three-forth (84.9%) of women who have NBW infants and more than half of mothers of LBW infants (62.5%) received nutritional advice during pregnancy (p=0.01). Almost 67.7% of mothers of LBW infants did not taken iron during pregnancy where as 69.5% of mothers of NBW infants taken iron supplement during pregnancy (P=0.002). The mean (± SD) hemoglobin level of mothers who have LBW babies were 15g/dl (±1.24 g/dl) whereas for mothers who have NBW babies were 14mg/dl (±1.81g/dl) (p=0.250). Almost 14.1% of mothers with NBW babies and 18% of mothers with LBW babies have hemoglobin level of less than 11 mg/dl which is indicative of anemia (p=0.131) (Table 3)
Table 3
Distribution of mothers by nutritional and dietary factors in Sidama Zone selected government hospital, Ethiopia, June 2018.
Variables
|
LBW
|
NBW
|
x2P –Value
|
Frequency
|
%
|
Frequency
|
%
|
Maternal Height
|
|
|
|
|
|
≥1.45cm
|
83
|
84.5
|
366
|
95.3
|
0.002*
|
<1.45cm
|
13
|
13.5
|
18
|
4.7
|
|
Maternal MUAC
|
|
|
|
|
|
<23cm
|
65
|
67.7
|
236
|
61.5
|
0.213
|
≥23cm
|
31
|
32.3
|
148
|
38.5
|
|
Nutritional advice during pregnancy
|
|
|
|
|
|
Yes
|
60
|
62.5
|
326
|
84.9
|
0.001*
|
No
|
36
|
37.5
|
58
|
15.1
|
|
Number of meal per day
|
|
|
|
|
|
≥3
|
72
|
75.0
|
370
|
96.4
|
0.004*
|
<3
|
24
|
25.0
|
14
|
3.6
|
|
Iron supplement during pregnancy
|
|
|
|
|
|
Yes
|
31
|
32.3
|
267
|
69.5
|
0.002*
|
No
|
65
|
67.7
|
117
|
30.5
|
Maternal hemoglobin level
|
|
|
|
|
|
≥ 11 g/dl
|
78
|
81.2
|
330
|
85.9
|
0.131
|
< 11 g/dl
|
18
|
18.8
|
54
|
14.1
|
*significant association at P- value of 0.05.
|
Risk factors for low birth weight
Bivariable logistic regression analyses for risk factors for LBW were performed. Maternal age, place of residence, marital status, maternal occupation, family monthly income, maternal height, maternal MUAC, number of children, number of ANC visit, gestational weeks at delivery, history of pregnancy complications, parity, sex of the new born, nutritional advice during pregnancy, number of meal per day, iron supplement during pregnancy, hemoglobin level were analyzed. The analyses revealed that religion, ethnicity, place of residence, marital status, maternal educational status, maternal occupation, family monthly income, maternal height, maternal MUAC, number of ANC visit, gestational age at delivery, history of pregnancy complications, parity, sex of the new born, nutritional advice during pregnancy, number of meal per day, iron supplement during pregnancy, hemoglobin level have p-value of less than 0.25 in bivariable model. Multivariable logistic regression was carried out for risk factors, which have p-value less than 0.25 in bivariable logistic regression models. From this maternal residence, marital status, gestational age at delivery, history of pregnancy complications and iron supplement during pregnancy shows association with LBW.
Maternal residence has influence on birth weight. Compared to maternal residents, the odds of delivering LBW babies were 2.5 times more in rural than urban residents (AOR=2.52(95% CI=1.15-5.82). The odd of LBW in mothers whose marital status is divorced or widowed were nearly six times more as compared to those mothers who were married (AOR=5.97 (95% CI =2.19-16.28)).
The odds of LBW for gestational age less than 37 weeks were 2.78 times more as compared to the those whose gestational age greater than 37 weeks (AOR=2.78(95% CI=1.27-6.06)). Compared to mothers who have not history of pregnancy complication, the odd of delivering LBW were 2.67 times more in mothers who have history of pregnancy complication [AOR=7.60 (95% CI= (2.03-28.45)]. The odds of LBW for mothers who were not took iron during pregnancy is 12.5 times more LBW than those who took iron during pregnancy (AOR=12.5(95 CI=5.06-31.0) (Table 4).
Table 4
Output of bivariable and multivariable logistic regression analysis for risk factors for low birth weight in Sidama zone selected Hospital, June 2010
Variable
|
Frequency (%)
|
COR (95%CI)
|
AOR (95%CI)
|
LBW NBW
|
Age (Years)
|
|
|
|
|
<20
|
15 (15.6)
|
36 (9.4)
|
0.91(0.35-2.31)
|
|
20-35
|
71 (74.0)
|
326 (84.9)
|
0.48(0.22-1.05)
|
|
>35
|
10 (10.4)
|
22 (5.7)
|
1
|
|
Residence
|
|
|
|
|
Urban
|
34 (35.4)
|
252 (65.6)
|
1
|
1
|
Rural
|
62 (64.6)
|
132(34.4)
|
3.51(2.19-5.65)
|
2.55(1.15-5.82)*
|
Marital Status
|
|
|
|
|
Married
|
69 (71.9)
|
363 (94.5)
|
1
|
1
|
Divorced/Widowed
|
27 (28.1)
|
21 (5.5)
|
6.76(3.61-12.64)
|
5.97(2.19-16.28)*
|
ANC visits
|
|
|
|
|
One visit
|
23 (24.0)
|
13 (3.4)
|
5.90(2.38-14.8)
|
3.82(0.94-15.41)
|
Two visit
|
19 (19.8)
|
62 (16.1)
|
1.80(0.90-3.62)
|
0.87(0.29-2.59)
|
Three visit
|
28 (29.2)
|
142 (37.0.2)
|
1.28(0.71-2.32)
|
0.74(0.30-1.79)
|
Four visit
|
26 (27.1)
|
167 (43.5)
|
1
|
1
|
Height
|
|
|
|
|
≥1.45m
|
83(84.5)
|
366(95.3)
|
1
|
1
|
<1.45m
|
13(13.5)
|
18(4.7)
|
3.18(1.50-6.76)
|
2.24(0.36-14.69)
|
MUAC
|
|
|
|
|
≥23 cm
|
65 (67.7%)
|
236 (61.5)
|
1
|
1
|
<23 cm
|
31 (32.3)
|
148 (38.5)
|
1.31(0.81-2.11)
|
0.91(0.45-1.84)
|
Gestational week
|
|
|
|
|
≥37
|
51 (53.1)
|
319 (83.0)
|
1
|
1
|
<37
|
45 (46.9)
|
65 (17.0)
|
2.82(1.724.61)
|
2.78(1.27-6.06)*
|
History of pregnancy complication
|
|
|
|
|
No
|
18 (18.8)
|
64(16.7)
|
1
|
1
|
Yes
|
78 (81.3)
|
30 (83.3)
|
2.15(1.49-4.55)
|
7.60(2.03-28.45)*
|
Nutritional advice during pregnancy
|
|
|
|
|
Yes
|
60(62.5)
|
326(84.9)
|
1
|
1
|
No
|
36(37.5)
|
58(15.1)
|
3.37(2.04-5.55)
|
076(0.30-1.91)
|
Iron supplement during pregnancy
|
|
|
|
|
Yes
|
31 (32.3)
|
267 (69.5)
|
|
1
|
No
|
65 (67.7)
|
117 (30.5)
|
12.32(6.81-22.28)
|
12.5(5.06-31.0)*
|
Maternal Hemoglobin level
|
|
|
|
|
≥ 11 mg/dl
|
78 (81.2)
|
330 (85.9)
|
1
|
1
|
< 11mg/dl
|
18 (18.8)
|
54 (14.1)
|
1.41(0.78-2.53)
|
1.63(0.38-6.90)
|
Sex of newborn
|
|
|
|
|
Male
|
45 (46.80
|
221 (57.5)
|
1
|
1
|
Female
|
51 (53.1)
|
163 (42.4)
|
1.54(0.98-2.41)
|
1.29(0.62-2.47)
|
* show statistically significant association for risk factors for LBW.
|