Table 2.

Alcohol and Substance Use Patterns by Study Group (N= 91)

	Controls (n= 34)	MAT (n= 19)	Alcohol (n= 15)	Alcohol+MAT (n= 23)	p^a
Alcohol Use:
12 months prior to enrollment:
AUDIT past 12 months: (Mean ± SD)	0.65 ±0.77	0.58 ±0.90	12.7 ±9.9	10.1 ±7.5	<0.001^w
AUDIT≥8: n (%^b)	0 (0.0)	0 (0.0)	9 (60.0)	12 (52.2)	<0.001
Periconceptional period:^c
AA/day: (Mean ± SD)	0.00±0.01	0.00±0.00	1.55 ±2.13	0.84 ±1.70	<0.001
During pregnancy beyond periconceptional period:
Maximum number of drinks in 24 hours	0.00±0.00	0.13±0.55	10.7 ±13.5	8.8 ±11.0	<0.001
AA/day average across pregnancy	0.00±0.00	0.00±0.00	0.12 ±0.41	0.005 ±0.02	0.103
Positive for ≥1 ethanol biomarker at study visit 1 or visit 2: n (%)	0 (0.0)	0 (0.0)	9 (60.0)	14 (60.9)	<0.001
Substance Use During Pregnancy:
MAT (methadone, buprenorphine): n (%)	0 (0.0)	19 (100)	0 (0.0)	23 (100)	<0.001
Other opioids: n (%)	0 (0.00)	12 (63.2)	3 (20.0)	12(52.2)	<0.001
Marijuana: n (%)	0 (0.00)	6 (31.6)	6 (40.0)	8 (34.8)	<0.001
Cocaine: n (%)	0 (0.0)	1 (5.3)	2 (13.3)	3 (13.0)	0.068
Methamphetamine: n (%)	0 (0.0)	3 (15.8)	0 (0.0)	2 (8.7)	0.036
Tobacco: n (%)	0 (0.0)	14 (73.7)	3 (21.4)	15 (65.2)	<0.001

MAT, opioid maintenance therapy.

AA, absolute ounces of alcohol (1 standard drink = approximately 0.5 AA)

For the continuous variables, p-values corresponds to an ANOVA F-test or Welch's modified F-test. For the categorical variables, p-values correspond to the Fisher's exact test.

All percentages are column percentage with each of the study groups as the denominator

One month around LMP

Welch's modified F-test was used to assess significant differences in the means instead of the ANOVA F-test