“…Nicotine, the dependence‐producing drug in ECIGs, is a toxicant of particular concern for pregnant women, as nicotine is known to harm a fetus (e.g., Bruin, Gerstein, & Holloway, ; England et al, ) some have suggested that no amount of nicotine in pregnancy is safe (CDC, ; Suter, Mastrobattista, Sachs, & Aagaard, ). ECIGs differ dramatically in terms of their nicotine delivery, with some products delivering little to no nicotine (e.g., Farsalinos et al, 2014; Vansickel et al, 2010; Yan & D'Ruiz, 2015), and others delivering as much, or more, than a combustible cigarette (e.g., Ramoa et al, 2016; St. Helen, Havel, Dempsey, Jacob III, & Benowitz, ; Wagner et al, ).…”