Murphy, Neil J.

Cigarette smoking is associated with numerous adverse pregnancy outcomes, due in part to polycyclic aromatic hydrocarbons and free radicals produced by combustion. Less is known about the impact of smokeless tobacco (ST) use during pregnancy. Alaska Native women report higher rates of cigarette and ST use during pregnancy than non-Native women. We investigated oxidative stress and hypoxia pathways in term placentae from Alaska Native women who did (commercial or iqmik; n = 10) or did not ( n = 18) use ST during pregnancy. Despite substantial maternal exposure to nicotine, placentae of women who used ST had similar mRNA levels of antioxidant enzymes and markers of hypoxia compared to those who did not use tobacco. Although mRNA levels of angiogenesis markers vegf and vegfr2 were similar between groups, vegfr1 mRNA levels are increased in placentae of women using ST compared to women who did not use tobacco. Together these results suggest that, while ST use may not have as significant an effect on oxidative stress pathways in the placenta as cigarette smoking, an effect is present. It is not clear what this limited effect may have on the developing fetus.

Prior research explored reasons for tobacco use among pregnant Alaska Native (AN) women but did not address the postpartum period. This study followed up with AN women one to three years postpartum who had participated in a prenatal smoking cessation intervention study (Motivate Alaska Women (MAW) Phase 3) and had consented to be re-contacted for future studies. Of 47 eligible women, 32 (68%) participated. A semi-structured phone interview was conducted a mean of 2.0 years after delivery (range 1.6–2.8). Measures assessed self-reported tobacco use status in the 12 months after delivery, at 12 months postpartum, and at the time of the interview; reasons for maintaining abstinence, continued use, or relapse; and included the Perceived Stress Scale (PSS) and Negative Affect (NA) scale. Content analysis was used to generate themes from open-ended response items. Tobacco use was reported by 23 women (72%) at delivery, 30 (94%) within the 12 months after delivery, 27 (84%) at 12 months postpartum, and 29 (91%) at the time of the interview. Among nine women not using tobacco at delivery, seven (78%) relapsed during the 12 months after delivery. Of the 29 current tobacco users, 28 (97%) smoked cigarettes. Twenty-seven participants (84%) reported stress and 15 (52%) indicated addiction as reasons for continuing, starting, or resuming tobacco use. Types of stressors were related to parenting and traumatic experiences. Among current tobacco users, mean NA score (18.7) was significantly higher (p = 0.01) than the normative mean (14.8), but no differences were detected for PSS score. In this sample of AN women, postpartum tobacco use was highly prevalent, and stress was a primary reason that women endorsed for using tobacco. These preliminary results have several practice and research implications for exploring ways to support non-tobacco use among postpartum AN women.