A harmonized analysis of five Canadian pregnancy cohort studies: exploring the characteristics and pregnancy outcomes associated with prenatal alcohol exposure

Table 8 Frequencies and percentages for preterm and very preterm births and low birthweight percentiles from singleton births across cohorts

	AOF		APrON		FAMILY		OBS		3D		Total
	(N = 3,125)^a		(N = 1,866)		(N = 765)		(N = 1,347)		(N = 2,251)		(N = 9,354)
	n	%	n	%	n	%	n	%	n	%	n	%
Gestational age < 37 weeks	199	6.4	88	4.7	53	6.9	71	5.3	152	6.8	563	6.0
Gestational age < 32 weeks	22	0.7	8	0.4	8	1.1	6	0.5	35	1.6	79	0.8
Birthweight < 10^th percentile^b	375	12.0	232	12.4	68	8.9	179	13.3	264	11.7	1118	12.0
Birthweight < 3^rd percentile	96	3.1	59	3.2	19	2.5	35	2.6	75	3.3	284	3.0

^a N = Number of participants from each cohort with non-missing values for the harmonized variable ‘gestational age at delivery’
^b Percentiles based on reference ranges adjusted for gestational age and infant sex from Canadian singletons described by Kramer et al. 2001 [45]

ISSN: 1471-2393