Nicotine replacement therapy is safer than smoking during pregnancy, a new review in the Medical Journal of Australia has found.

Nicotine replacement therapy (NRT) is safer than smoking and Australian doctors can be confident about prescribing it for 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 co-author Dr Yael Bar-Zeev, 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.”

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)”.

Associate Professor Gillian Gould, HMRI’s Early Career Researcher of the Year, said nicotine replacement therapy could also be the solution to help smokers quit throughout their pregnancy, and clinicians needed to have the discussion with their patients who were pregnant and unable to quit cold turkey.

“When you smoke cigarettes, you’re getting 7,000 different toxic chemicals and you’re breathing in carbon monoxide, which attaches to the blood cells and then the baby doesn’t get the right amount of oxygen through the placenta,” she told ABC News.

“Nicotine is only one chemical among those 7,000 … and we believe the nicotine you have in nicotine replacement therapy is much lower in dosage. It’s more regulated and it’s not absorbed as much as the nicotine in cigarettes. So it’s far less dangerous to take nicotine replacement therapy than to smoke.”

Dr 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.”

The research team concluded that “nicotine may not be completely safe for the pregnant mother and fetus, but it is always safer than smoking”.