Nicotine replacement in pregnancy: Safer than smoking

Monday, 4 December 2017


Nicotine replacement therapy (NRT) is safer than smoking and Australian doctors can be confident about prescribing it for their pregnant patients, according to the authors of a Narrative Review published online by the Medical Journal of Australia.

“Clinicians report low levels of prescribing NRT during pregnancy, due to safety concerns and low levels of confidence in their ability to prescribe NRT,” wrote the authors, led by Dr Yael Bar-Zeev, Public Health physician and Tobacco Treatment Specialist, PhD candidate at the University of Newcastle and head of the Centre for Smoking Cessation and Prevention at Ben-Gurion University in Israel.

“In a recent survey of Australian general practitioners and obstetricians, 25% of participants stated that they never prescribe NRT during pregnancy,” Dr Bar-Zeev and co-authors Associate Professor Gillian Gould, Professor Billie Bonevski, Associate Professor Maree Gruppetta and Ling Li Lim added.

Current Australian and New Zealand guidelines recommend the use of NRT by pregnant women who have been unable to quit smoking without medication, the authors wrote. However, these guidelines, and others from around the world,deliver mixed messages by imposing caveats such as “only if women are motivated”, “only give out 2 weeks’ supply” or “under close supervision”.

In laboratory studies nicotine has been shown to cause damage to the lungs and central nervous systems of the fetus; however, “human studies … did not find any harmful effects on fetal and pregnancy outcomes compared with placebo, but the evidence is limited due to the small numbers of participants in the meta-analysis (combining all studies together)”.

Bar-Zeev and colleagues provided a practical guide for general practitioners for prescribing NRT to their pregnant patients.

“As many pregnant women reduce on their own the number of cigarettes they smoke, using measures that rely on number of cigarettes per day may be less effective,” they wrote. “We suggest using the strength of urges to smoke (SUTS) and the frequency of urges to smoke (FUTS) scales as practical guides to the decision to initiate or increase the NRT dose … If the women report experiencing strong or frequent … urges to smoke, this suggests the need for additional support.

“The most important guidance for NRT in pregnancy is to use the lowest possible dose that is effective. However, to be effective, women should … use as much as needed to deal with cravings. Physicians should encourage using oral NRT regularly throughout the day to substitute for cigarettes; for example, a woman smoking ten cigarettes a day should be instructed to use one piece of gum every 1.5 hours regularly, even if she is not experiencing a strong craving at this time.

“In addition, physicians should encourage the use of oral NRT in anticipation of cravings; if a woman knows she is going to be in a situation where the urge to smoke will be strong (eg, going out with friends who smoke), doctors should encourage the use of oral NRT 20 minutes beforehand. Physicians should proactively review … on a weekly basis and adjust dosage as needed.

“Further, women should be encouraged to use NRT for at least 12 weeks, or longer if required, in order not to relapse.”

Bar-Zeev and colleagues concluded that “nicotine may not be completely safe for the pregnant mother and fetus, but it is always safer than smoking”.

“A risk and benefit analysis needs to be done to help pregnant women (and their partners) judge whether to use a clean source of nicotine such as NRT, which might help cessation, and whether this is preferable to continuing exposure to the nicotine and other chemicals present in combustible cigarettes.”