Concentrations of persistent organic pollutants in maternal and cord blood from the maternal-infant research on environmental chemicals (MIREC) cohort study

Table 1 Study population

Characteristic	Frequency	Percent
Maternal age group
<25	139	7.01
25–29	459	23.15
30–34	709	35.75
35+	676	34.09
Smoking status
Current	237	11.96
Former	542	27.36
Never	1202	60.68
Country of birth
Foreign born	371	18.71
Canadian born	1612	81.29
Maternal education
High school or less	175	8.83
Some college or college degree	572	28.87
Undergraduate degree or higher	1234	62.29
Marital status
Married	1424	71.81
Other	559	28.19
Income
≤$50,000	347	17.49
$50,001–$100,000	786	39.64
More than $100,000	757	38.17
Parity
0	874	44.12
1	800	40.38
2+	307	15.5
Body mass index (BMI)
Underweight to normal (BMI <25)	1164	63.36
Overweight (25 ≤ BMI <30)	404	21.99
Obese (BMI >30)	269	14.64
Fasting status
No	1914	98
Yes	39	2
Season of sampling (1st trimester)
Fall	575	29.41
Spring	448	22.92
Summer	464	23.73
Winter	468	23.94
Infant gender
Male	1034	52.51
Female	926	47.03
Babies
Singletons	1934	97.53
Twins	47	2.37
Triplets	2	0.10

Note: for income and infant gender, sum of percent is not 100, because there is a group (don’t know) was not included

ISSN: 1476-069X