Table 1.

Characteristics of women who smoked in the 3 months before pregnancy, by exposure to Tips 2012: Indiana, Kentucky, Ohio, 2009–2013

Maternal characteristics*	Unexposed† % (n=209 053)	Exposed‡ % (n=60 747)	p Value§
Mean maternal age (years)	25.2 (±5.3)	25.6 (±5.3)	<0.0001
Maternal race/ethnicity
White, non-Hispanic	86.5	86.1	<0.0001
Black, non-Hispanic	10.3	10.3
Hispanic	2.3	2.4
Other	0.9	1.2
Maternal education
<High school	27.0	24.3	<0.0001
High school or GED	38.0	37.9
College of graduate	35.0	37.8
Marital status
Married	33.1	31.7	<0.0001
Unmarried	66.9	68.3
Parity
First birth	38.5	37.2	<0.0001
Second or later birth	61.5	62.8
Missing§
WIC enrolment
No	32.7	33.6	<0.0001
Yes	67.3	66.4
Prepregnancy BMI
Underweight (<18.5)	6.9	6.6	<0.0001
Normal weight (18.5–24.9)	44.6	43.6
Overweight (25–29.9)	23.1	23.4
Obese (≥30)	25.4	26.4
Insurance status
Medicaid	67.4	67.3	0.0261
Private insurance	23.7	24.1
Self-pay	2.2	2.3
Other	6.7	6.4
State
Indiana	27.5	26.9	<0.0001
Kentucky	21.7	23.3
Ohio	50.7	49.8
Cigarette smoked per day before pregnancy
1–10	21.0	22.6	<0.0001
11–20	30.7	31.8
≥21	48.3	45.5

BMI, body mass index; GED, General Educational Development; WIC, Woman, Infants and Children.

*Missing values not included in column totals: maternal age, 0.1%; race/ethnicity, 0%; education, 0.7%; marital status, 0.3%; parity, 0%; WIC enrolment, 0.6%; BMI, 2.2%; insurance, 1.3%; state, 0%; cigarettes/day, 0%.

†Women who delivered prior to the Tips 2012 campaign (1 January 2009 to 18 March 2012).

‡Women for whom there was temporal overlap between the Tips 2012 campaign and the period including her pregnancy and the preceding 3 months. Women only exposed during the third trimester were excluded.

§Student’s t-tests used for continuous variable (age) and χ² test used for categorical variables.