Prognostic factors for low birthweight repetition in successive pregnancies: a cohort study

Table 1 **Low birthweight recurrence [LBWR]* according to maternal socio-economic and biological characteristics**

Variable	N [%]	LBWR [%]	p
Economic status ^a [n = 408] ^b			0.008 ^c
A and B	58 [14.2]	2 [3.5]
C	119 [29.2]	9 [7.5]
D	168 [41.2]	26 [15.5]
E (poorest)	63 [15.4]	14 [22.2]
Father’s schooling (years) [n = 481] ^b			0.04 ^c
0 – 4	113 [23.5]	23 [20.3]
5 – 8	208 [43.2]	31 [14.9]
≥ 9	160 [33.3]	18 [11.2]
Mother’s schooling (years) [n = 563] ^b			< 0.001 ^c
0 – 4	132 [23.4]	32 [24.2]
5 – 8	261 [46.4]	39 [14.9]
≥ 9	170 [30.2]	15 [8.8]
Marital status [n = 565]			0.74 ^d
Living with partner	65 [11.5]	9 [13.8]
Living without partner	500 [88.5]	77 [15.4]
Mother’s age [n = 564] ^b			0.71 ^c
15 - 20	82 [14.5]	13 [15.8]
21 - 25	162 [28.7]	27 [16.7]
26 - 30	136 [24.1]	17 [12.5]
31 - 35	108 [19.1]	17 [15.7]
36 - 44	76 [13.5]	11 [14.5]
Mother’s skin color [n = 565]			0.65 ^d
White	384 [68.0]	61 [15.9]
Non-white	142 [25.1]	21 [14.8]
Other	39 [6.9]	4 [10.3]
Father’s age [n = 552] ^b			0.53 ^c
16 - 20	23 [4.2]	6 [26.1]
21 - 25	123 [22.3]	19 [15.4]
26 - 30	127 [23.0]	17 [13.4]
31 - 35	134 [24.3]	19 [14.2]
36 - 64	145 [26.8]	22 [15.2]
Mother’s height [cm] [n = 475] ^b			0.63^c
<150	23 [4.8]	6 [26.1]
150 - 154	60 [12.6]	10 [16.7]
155 - 159	88 [18.5]	15 [17.0]
160 - 164	95 [20.0]	10 [10.5]
≥165	209 [44.0]	37 [17.7]
LBW born-mother [n = 377] ^b			0.004 ^d
No	320 [84.9]	39 [12.2]
Yes	57 [15.1]	15 [26.3]
Preterm born-mother [n = 510] ^b			0.004^d
No	473 [92.7]	63 [13.3]
Yes	37 [7.3]	11 [29.7]

* LBWR defined as birth weight < 2,500 g in the index pregnancy (pregnancy that ended in 2004) amongst women with at least one previous LBW newborn in the two immediate pregnancies before the pregnancy that ended in 2004.
a: Brazilian Research Companies Association; b: Indicates missing values; c: Linear trend; d: Chi-squared test for heterogeneity.

ISSN: 1471-2393