TABLE 1.

Maternal and infant characteristics

	Mbekweni (black African)	Newman (mixed ancestry)	Total	p-value
Maternal characteristics
Mothers	530 (54%)	452 (46%)	982 (100%)
Age at enrolment years	26.9 (22.3, 31.6)	24.6 (21.3, 29.1)	25.8 (22.0, 30.6)	<0.001
HIV-infected	193 (36%)	13 (3%)	206 (21%)	<0.001
Unemployed	400 (75%)	325 (72%)	724 (74%)	0.205
SES quartile
Lowest SES	157 (30%)	80 (18%)	237 (24%)	<0.001
Low–moderate SES	150 (28%)	109 (24%)	259 (26%)
Moderate–high SES	126 (24%)	127 (28%)	253 (26%)
Highest SES	97 (18%)	136 (30%)	233 (24%)
Household members	4 (3, 6)	5 (4, 7)	4 (3, 6)	<0.001
Married/cohabiting	188 (35%)	194 (43%)	382 (39%)	0.017
Infant characteristics and birth outcomes
Number of infants; sets of twins	534 (54%); 4	452 (46%); 0	986 (100%); 4
Female	280 (52%)	204 (45%)	484 (49%)	0.022
Gestation at delivery weeks	39 (38, 40)	39 (37, 40)	39 (38, 40)	0.032
Birthweight g	3180 (2810, 3460)	2990 (2630, 3340)	3080 (2720, 3415)	<0.001
Weight-for-age z-score	−0.4 (−1.3, 0.2)	−0.7 (−1.4, −0.1)	−0.6 (−1.3, 0.0)	<0.001
Birthweight <2500 g	55 (10%)	83 (18%)	138 (14%)	<0.001
Birth <37 weeks gestation	16 (3%)	19 (4%)	35 (4%)	0.314
Feeding at 6 months
Exclusive breastfeeding	76 (14%)	66 (15%)	142 (14%)	<0.001
Mixed	89 (17%)	170 (38%)	259 (26%)
Not breastfeeding	369 (69%)	216 (48%)	585 (59%)
Duration of exclusive breastfeeding months	1.1 (0.5, 3.0)	1.6 (0.9, 3.0)	1.4 (0.7, 3.0)	0.410
Day care attendance
6 months of age	17 (3%)	28 (6%)	45 (5%)	0.024
12 months of age	69 (13%)	90 (20%)	159 (16%)	0.003
Additional child under 5 years of age in household	455 (85%)	396 (88%)	851 (86%)	0.274
Respiratory infection in prior month
6 months of age	40 (7%)	37 (8%)	77 (8%)	0.685
12 months of age	29 (5%)	22 (5%)	51 (5%)	0.691
Antibiotic use in prior 6 months
6 months of age	25 (5%)	38 (8%)	63 (6%)	0.057
12 months of age	14 (3%)	13 (3%)	27 (3%)	0.957

Data are presented as median (interquartile range), unless otherwise stated. SES: socioeconomic score.