The overall goal of this pilot study is to develop and preliminarily evaluate an LPA intervention designed to reduce cannabis use during pregnancy.

In the pilot RCT, we will recruit 50 women between 12-22 weeks gestation from an established network of prenatal clinics, and randomly assign eligible women to either a: 1) LPA+Fitbit intervention or 2) Fitbit Only control condition. Similar to our prior trials with pregnant women, the intervention period will be 12 weeks in duration during pregnancy, with follow-ups extending to the end of pregnancy and into the postpartum period. Major assessments will occur at baseline, end of treatment (EOT), and 4 weeks postpartum; we will also conduct brief phone surveys at three points in between the larger assessments. Participants will complete a 7-day period of accelerometry and urine toxicology screens following each major assessments. Birth record abstractions to collect information about specific outcomes (pre-term delivery, low birth weight) will be conducted by trained staff at one month post-birth.

Inclusion Criteria:

1. women 18+ years of age
2. 12-25 weeks gestation with a healthy singleton pregnancy
3. medically-cleared by their prenatal provider for moderate intensity physical activity
4. self-report of cannabis use at least once/week in the 3 months prior to the current pregnancy and desire to not engage in prenatal CU
5. current psychological distress as defined by Edinburgh Postnatal Depression Scale score >7 and/or Generalized Anxiety Disorder 7 score >5)
6. English-speaking
7. owns a smartphone to enable use of the Fitbit app
8. current physical activity level does not meet public health recommendations (less than 150 minutes/week moderate intensity physical activity for the past 3 months)
9. expresses interest in reducing or discontinuing CU

Exclusion Criteria:

1. current DSM-5 diagnosis of moderate/severe substance use disorder other than cannabis use disorder or nicotine use disorder
2. use of illicit substances in the last 3 months (other than cannabis)
3. acute psychotic symptoms
4. current or recent suicidality or homicidality
5. current anorexia or bulimia
6. current cognitive impairment
7. physical or medical problems that would not allow safe participation in moderate intensity physical activity
8. has plan to relocate away from the geographic area during the study intervention or assessment period
9. recently started a new form of mental health or substance use treatment within the past 4 weeks