Forty-one percent of the women reported working at a paid job for an average of 28.95 hrs a week (SD = 10.81 hrs). Measures Participants The initial sample consisted of 312 pregnant women who were first interviewed at the end of the first trimester between 12 and 20 weeks gestation. However, given that we were interested in partner EPZ-5676 Histone Methyltransferase smoking, we restricted our analyses to include only women who reported that they were in a relationship at the time of the first interview. Thus, our final sample consisted of 245 pregnant women who reported being in a serious relationship. All analyses were conducted with these 245 women with the exception of analyses regarding change in SHS exposure over pregnancy.

This is an ongoing longitudinal study, and to date, 106 women have completed all three prenatal interviews and the 2-month postnatal interview (in order to obtain information about smoking between the last prenatal interview and delivery). Accordingly, the sample for the change analysis was restricted to these 106 women. Potential differences between the 245 women with first trimester data and the 106 who have complete data at all three trimesters were examined using independent sample t tests. Results indicated that women with complete data for all three prenatal interviews did not differ from those with first trimester data with regard to gravidity, education, number of smokers living in their home, or any of our SHS measures, with the exception of frequency of smoke exposure in a car (t(242.85) = 2.09, p = .04, d = 0.27).

Women with first trimester data reported higher frequency of smoke exposure in a car compared to women with complete data. Chi-square difference tests further revealed that women who had complete data did not differ from those with first trimester data in terms of employment, smoking status, partner smoking status, race, or living status with their partner. Maternal Substance Use Participants were interviewed in a private setting by trained interviewers. The timeline followback interview (TLFB; Sobell, Sobell, Klajmer, Pavan, and Basian, 1986) was used to assess maternal substance use at each prenatal and the postnatal interview. Participants were provided a calendar and asked to identify events of personal interest (i.e., holidays, birthdays, vacations, etc.) as anchor points to aid recall.

This method has been established as a reliable and valid method of obtaining longitudinal data on substance-use patterns, has good test�Cretest reliability, and is highly correlated with other intensive self-report measures (Brown et al., 1998). At each prenatal appointment, TLFB was used to gather daily tobacco, alcohol, and cannabis use for the previous 3 months. Women who smoked blunts were asked how many joints they could have rolled from the amount of marijuana in the blunt. Thus, self-reported Brefeldin_A data spanned 3 months prior to conception through delivery.