Trial reportNicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco2019
Pregnancy-Induced Increases in the Nicotine Metabolite Ratio: Examining Changes During Antepartum and Postpartum.
Trial report in Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
16 citing papers in PubMed, 24 citations in OpenAlex.
- Pilot randomized clinical trial examining use of very low nicotine content cigarettes during pregnancy in the United States.Preventive medicine · 2025Trial
- Mechanisms of altered hepatic drug disposition during pregnancy: small molecules.Expert opinion on drug metabolism & toxicology · 2025Review
- PharmVar GeneFocus: CYP2A6.Clinical pharmacology and therapeutics · 2024Review
- Article
- The use of biomarkers to guide precision treatment for tobacco use.Addiction neuroscience · 2023Article
- Safety of Nicotine Replacement Therapy during Pregnancy: A Narrative Review.International journal of environmental research and public health · 2022Review
- Impact of Electronic Cigarette Vaping on Cerebral Ischemia: What We Know So Far.Translational stroke research · 2022Review
- Higher blood nicotine concentrations following smokeless tobacco (pituri) and cigarette use linked to adverse pregnancy outcomes for Central Australian Aboriginal pregnancies.BMC public health · 2022Article
- Maternal nicotine metabolism moderates the impact of maternal cigarette smoking on infant birth weight: A Collaborative Perinatal Project investigation.Drug and alcohol dependence · 2022Article
- Use of electronic nicotine delivery systems (ENDS) among U.S. women of reproductive age: Prevalence, reported reasons for use, and toxin exposure.Preventive medicine · 2021Article
- Nicotine metabolite ratio: Comparison of the three urinary versions to the plasma version and nicotine clearance in three clinical studies.Drug and alcohol dependence · 2021Article
- Nicotine and Its Downstream Metabolites in Maternal and Cord Sera: Biomarkers of Prenatal Smoking Exposure Associated with Offspring DNA Methylation.International journal of environmental research and public health · 2020Article
- Prenatal smoke exposure induces persistentEpigenetics · 2020Article
- Abuse liability of cigarettes with very low nicotine content in pregnant cigarette smokers.Preventive medicine · 2020Article
- The Use of the Nicotine Metabolite Ratio as a Biomarker to Personalize Smoking Cessation Treatment: Current Evidence and Future Directions.Cancer prevention research (Philadelphia, Pa.) · 2020Review
- Cigarette consumption and biomarkers of nicotine exposure during pregnancy and postpartum.Addiction (Abingdon, England) · 2018Article
Corrections and comments
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Authors and funding
6 authors at 2 institutions in 3 countries.
Funding
Abstract
introductionPregnancy-induced increases in nicotine metabolism may contribute to difficulties in quitting smoking during pregnancy. However, the time course of changes in nicotine metabolism during early and late pregnancy is unclear. This study investigated how pregnancy alters the nicotine metabolite ratio (NMR), a common biomarker of nicotine metabolism among nonpregnant smokers.
methodsUrinary NMR (trans-3'-hydroxycotinine [3HC]/cotinine [COT]) was assessed using total (free + glucuronide) and free compounds among women (N = 47) from a randomized controlled trial for smoking cessation who self-reported smoking and provided a urine sample during early pregnancy (M ± SD = 12.5 ± 4.5 weeks' gestation), late pregnancy (28.9 ± 2.0 weeks' gestation), and 6 months postpartum (24.7 ± 1.2 weeks since childbirth). Urine samples were analyzed using liquid chromatography-tandem mass spectrometry and NMR were calculated as Total 3HC/Free COT, Free 3HC/Free COT, and Total 3HC/Total COT.
resultsNMR was significantly higher during early and late pregnancy compared to postpartum and significantly increased from early to late pregnancy as measured by Total 3HC/Free COT (0.76, 0.89, 0.60; all p's < .05) and Free 3HC/Free COT (0.68, 0.80, 0.51; all p's < .05). Total 3HC/Total COT did not vary over time (p = .81).
conclusionsTotal 3HC/Free COT and Free 3HC/Free COT increased in the first trimester and continued to increase throughout pregnancy, suggesting a considerable increase in nicotine metabolism over gestation. Future analyses are needed to interpret the changes in NMR in the context of nicotine pharmacokinetics, as well as its impact on changes in smoking behavior and cessation outcomes. IMPLICATIONS: We observed that the NMR was significantly higher as early as 12 weeks' gestation and increased further as a function of gestational age. Among nonpregnant smokers, elevated NMR is associated with smoking phenotypes such as smoking more cigarettes per day and poorer response to nicotine patch; therefore, pregnancy-induced increases in the NMR may contribute to smoking during the first trimester of pregnancy and reducing or quitting smoking may become more challenging as the rate of nicotine metabolism accelerates over the course of pregnancy.
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