Table 3.

Frequency of risky drinking (3+ drinks) and demographic characteristics by trajectory class

Risky drinking frequency	C1: Low risk N=214 (49%)	C2: Postpartum initiation N=78 (21%)	C3: Moderate risk N=99 (24%)	C4: High risk N=24 (6%)
	% of C1	% of C2	% of C3	% of C4
T-2 (before pregnancy)
‘1x/month or more’	1.9%	0%	17.4%	78.3%
‘1x/week or more’	0.9%	0%	10.9%	69.6%
T-1 (before pregnancy)
‘1x/month or more’	1.4%	0%	43.4%	90.5%
‘1x/week or more’	1.0%	0%	25.6%	71.4%
T0 (during pregnancy)
‘1x/month or more’	0%	1.3%	27.3%	75.0%
‘1x/week or more’	0%	0%	16.2%	58.3%
T+1 (after pregnancy)
‘1x/month or more’	0%	34.3%	32.9%	83.3%
‘1x/week or more’	0%	17.1%	17.6%	55.6%
T+2 (after pregnancy)
‘1x/month or more’	0%	46.2%	22.5%	90.9%
‘1x/week or more’	0%	21.5%	10.0%	68.2%
Demographic variables	M (SD) or %	M (SD) or %	M (SD) or %	M (SD) or %
Age at first drink	16.81 (3.65)	15.46 (3.60)	14.39 (2.74)	13.96 (2.56)
Age at childbirth	18.78 (2.03)	19.50 (1.53)	20.04 (1.93)	21.27 (1.79)
Age group at pregnancy (T0)
Teenager (13-17)	34.1%	14.8%	14.9%	5.0%
Pre-legal adult (18-20)	54.3%	72.2%	50.7%	25.0%
Legal drinking age (≥ 21)	11.6%	13.0%	34.3%	60.0%
Living with caregiver
T0 (pregnancy)	63.3%	66.1%	56.6%	43.5%
T+1 (after pregnancy)	47.9%	34.3%	40.5%	33.3%
Living with intimate partner
T0 (pregnancy)	15.8%	19.3%	18.4%	21.7%
T+1 (after pregnancy)	16.1%	14.9%	10.7%	11.1%
Employed full- or part-time
T0 (pregnancy)	38.1%	40.0%	41.7%	65.2%
T+1 (after pregnancy)	41.2%	67.1%	58.8%	72.2%
Receiving WIC assistance
T0 (pregnancy)	32.7%	40.4%	40.3%	17.6%
T+1 (after pregnancy)	69.8%	67.9%	73.2%	66.7%

Note. T-2 = two years before pregnancy, T-1 = one year before pregnancy, T0 = during pregnancy, T+1 = one year after childbirth. T+2 = two years after childbirth. WIC = Women, Infants, and Children federal assistance supplemental nutrition program for low-income families