The use of nicotine replacement therapy (NRT) for pregnant women who smoke: A narrative review of placebo controlled randomized controlled trials to evaluate efficaacy and safety
Background: The use of tobacco during pregnancy is considered to be the most important preventable cause of pregnancy complications including pre-term labor and fetal growth restriction (3,9,10). Despite the potential for harmful effects, 10.5-23% of Canadian women smoke during pregnancy (4,5). While there is strong evidence that nicotine replacement therapy (NRT) is highly effective in reducing tobacco use in the general population (17), data supporting the use of NRT in pregnancy is limited. Objective: We conducted a narrative review of placebo-controlled randomizedcontrolled trials (RCTs) to evaluate the safety and efficacy of NRT use for pregnant women who smoke. Methods: A comprehensive review of the literature was performed using the Embase and Ovid MEDLINE database records from 1946 to December 2015. Articles were included if they were placebo-controlled RCTs testing the use of NRT in pregnant women who smoke. Primary outcome measures were daily tobacco use, cessation rates, and pregnancy complications. Results: Of the 407 articles retrieved, five met the inclusion criteria (total n = 1,926 participants). All included RCTs provided cessation counseling to study participants in addition to NRT or placebo. In the RCTs that found a significant difference between NRT and placebo, NRT was associated with a significantly larger reduction in daily tobacco use (cigarettes/day), as well as a significant increase in mean birth weight and a reduced incidence of pre-term birth. NRT use did not have a significant effect on cessation rates, NICU admissions, or the incidence of fetal demise. There were no significant adverse effects associated with NRT use. Conclusions: While additional research is still needed, the results of this narrative review suggest that NRT use may result in greater reductions in tobacco use than counseling alone. There is no evidence from this review that NRT increases the risk of fetal growth restriction, pre-term delivery, or NICU admissions.