Tobacco Info

From Tobacco Info No. 2 - September 2010
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Doctor recommends NRT use during pregnancy


I’m comfortable telling my patients to put a [nicotine] patch on or get some [nicotine] gum,” said Dr. Greg Davies, professor and chair of the Division of Maternal-Fetal Medicine at Queen’s University in Kingston, Ontario. “However, it is totally off label right now. It’s just a matter of time before there is a consensus as to the benefits of medicinal nicotine (NRT) versus the risks.


As part of his presentation at the Second Annual Ottawa Conference on State of the Art Clinical Approaches to Smoking Cessation in January, Davies suggested that medicinal nicotine is much less harmful than smoking cigarettes, and thus should be made readily available to women during pregnancy.


Concerns about using Nicotine Replacement Therapy (NRT) during pregnancy stem from the observed teratogenicity of nicotine itself, and whether there is a correlation between NRT and congenital anomalies, such as oral facial clefts or limb reductions. However, Davies suggests that there is no concrete evidence of a causal relationship, and if there is one, its risks would be minimal when compared to the risks associated with smoking.


Although this idea may be off the grid, Davies is not alone in his advocacy of NRT.


The Ontario Medical Association (OMA) published a position paper in 1999 suggesting that stop smoking therapies should be used by pregnant women if they are unable to quit on their own, and affirmed that the nicotine patch and gum are safer than smoking for the pregnant woman and her fetus. However, in a 2008 report, they reaffirmed that there is no real safe dose of nicotine for a fetus.


Meanwhile, in 2008, Health Canada, which had historically advised against the use of medicinal nicotine for pregnant women, softened its stance after examining reports conducted by Neil Benowitz et al. in 2000, and by Benowitz with Dalia Dempsey in 2001, whose findings encouraged the use of nicotine replacement therapies for women who “are unable to quit smoking during pregnancy after 12 weeks gestation to reduce damage caused by inhaled smoke to both the mother and the fetus.


According to the Canadian Tobacco Use Monitoring Survey (CTUMS) released by Statistics Canada in 2008, approximately 8.8% of Canadian women had smoked while pregnant within the previous five years. It is as high as 22% in the 20-24 age range.


Increased risks associated with smoking


Studies examined and collected by Davies, and showcased as part of his presentation entitled Smoking Cessation Strategies in Pregnancy at the Ottawa conference, demonstrated a two-fold risk of miscarriage, childhood obesity, stillbirths and ectopic pregnancies for women who smoke and a three-fold risk of developing placenta previa or having a child with attention deficit hyperactivity disorder (ADHD). There can be, according to Davies, a risk of up to eight times higher for sudden infant death syndrome (SIDS) in babies whose mother smoked during pregnancy.


Preterm births for babies born to mothers who smoke or are exposed to second-hand smoke are more common, and these babies weigh in at 250 g less than babies born to non-smokers; and can be up to 350 g smaller if the mother smokes more than 20 cigarettes a day. Increased risks of placental complications, neurobehavioral effects and transplacental carcinogenesis are also more common with smoking-related pregnancies.


Benefits of NRT


NRT avoids high nicotine levels, as well as the 4,000 other detrimental compounds found in cigarettes, so to me, the benefits are very clear,” said Davies.


According to Davies’ research, these increased risks diminish considerably if the woman quits smoking within the first trimester.


Using national data, Dr. Katrine Strandberg-Larsen and colleagues from the University of Southern Denmark in Copenhagen gathered information on NRT use and smoking for 87,032 singleton pregnancies. Two percent of women reported using nicotine replacement during pregnancy. Of these women, 14% had not smoked during pregnancy, 30% had quit smoking during pregnancy and 56% continued to smoke.


The study found that of the 87,032 pregnancies, there were 495 stillbirths, only eight of which were among the group of NRT users. Those women who did use NRT had a 43% lower risk of stillbirth after accounting for other risk factors. Even for women who continued to smoke while using NRT to quit or cut down, the risk was reduced by 17% compared to non-users.


By comparison, smokers who did not use NRT during pregnancy had a 46% higher risk of having a stillbirth.


Ultimately, the best advice for pregnant women is to quit altogether, but if they are unable to [beat their nicotine addiction], then I’d recommend using NRT,” said Davies.


– by Joe Strizzi