Gestational age at birth and morbidity, mortality, and growth in the first 4 years of life: findings from three birth cohorts in Southern Brazil

Table 1 Frequency of different outcomes during the first four years of life according to gestational age

Outcome	Cohort	Number in the analyses	Gestational age in completed weeks						All	P value
			<34	34-36	37	38	39-41	42+
Neonatal mortality/1,000	All	13273	168	19	11	8	4	9	12	<0.001
Infant mortality/1,000	All	13273	189	40	23	14	10	17	21	<0.001
Total breastfeeding (months) (mean)	All	9453	6.1	7.5	8.4	8.3	8.1	7.7	8.0	0.004
Hospitalization 0–12 mo (%)	All	6071	38.1	26.1	18.0	16.6	14.3	15.2	17.1	<0.001
WAZ < −2 at 12 mo (%)	All	6059	6.8	4.5	2.7	2.0	1.5	2.8	2.3	<0.001
HAZ < −2 at 12 mo (%)	All	6048	14.5	10.3	6.6	6.1	5.6	6.3	6.6	<0.001
WHZ > 2 at 12 mo (%)	All	6048	4.7	6.4	10.4	8.5	8.4	7.8	8.2	0.06
WAZ < −2 at 48 mo (%)	All	8442	3.3	2.7	1.6	1.7	1.8	1.7	1.9	0.27
HAZ < −2 at 48 mo (%)	All	8442	7.9	6.8	5.4	5.4	6.5	7.5	6.4	0.29
WHZ > 2 at 48 mo (%)	All	8442	9.2	7.9	10.1	10.8	9.6	9.2	9.7	0.45
Number of births in the 3 cohorts	All		869	1497	1434	2431	8287	1259	15777

Pelotas (Brazil) Birth Cohorts 1982, 1993, 2004.
Abbreviation: WAZ: weight for age z-score; HAZ: height for age z-score; WHZ: weight for height z-score.

ISSN: 1471-2431