Variations in nicotine metabolism influence smoking patterns. Differences between sexes or related to sex hormones may affect nicotine metabolism. Because smoking initiation starts during adolescence, observations gathered from adolescent smokers might broaden our understanding of such sex-based differences. We tested the hypothesis that nicotine metabolism--as indexed primarily by the ratio of trans-3'-hydroxycotinine (3HC) to cotinine--is more rapid among adolescent girl smokers compared with boys and that regular use of hormonal contraceptives influences nicotine and cotinine metabolism. We also hypothesized that more rapid nicotine metabolism is associated with higher nicotine dependence as indexed by smoking frequency and morning urgency. Plasma samples of nicotine, cotinine, and 3HC concentrations were obtained from 120 adolescents (36 boys). Plasma nicotine and cotinine concentrations were similar in boys and girls. Median plasma 3HC concentrations were 44.45 ng/ml for girls versus 35.74 ng/ml for boys (p = .025), and median plasma 3HC-cotinine ratios were significantly higher in girls than in boys (0.317 vs. 0.253, p = .025). After stratifying girls into two groups based on use versus nonuse of hormonal contraception, plasma 3HC-cotinine ratios in girls using hormonal contraception (0.47) were substantially higher (p<.0001) than in boys (0.25) and were significantly higher than in girls not using hormonal contraception (0.28). Controlling for cigarettes smoked per day, ethnicity, and age did not modify these results. Although plasma nicotine, cotinine, or 3HC concentrations were significantly lower in less dependent adolescent smokers, nicotine and cotinine metabolite ratios were similar. This study showed that hormonal contraception in adolescent girls may accelerate cotinine metabolism, an effect likely related to induction of cytochrome P450 2A6 and independent of ethnicity and cigarette consumption. Prospective controlled studies are needed to further evaluate the role of hormonal contraception in patterns of adolescent smoking and nicotine metabolism.
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http://dx.doi.org/10.1080/14622200701243193 | DOI Listing |
Oestrogen and progesterone fluctuate cyclically in women throughout their adult lives. Although these hormones cross the blood-retinal barrier and bind to intraocular receptors, their effects remain unclear. We present the first review to date on associations between posterior pole structures-specifically the macula, choroid, and optic disc-and both the menstrual cycle and post-menopausal period, utilising multimodal imaging techniques in healthy adult non-pregnant women.
View Article and Find Full Text PDFBMJ Sex Reprod Health
January 2025
Obstetrics and Gynaecology, University of Edinburgh, Edinburgh, UK.
Background: Recent media attention has been given to an apparent shift away from hormonal methods of contraception. While an increase in fertility awareness-based or 'natural' family planning methods is reported in the grey literature, there are no robust data to determine any such trend in the UK.
Methods: We compared self-reported contraceptive use at conception among patients presenting for abortion at British Pregnancy Advisory Service from January to June 2018 (N=33 495) and January to June 2023 (N=55 055) using chi-square (χ) tests of association.
Eur J Obstet Gynecol Reprod Biol
January 2025
Department of Human Physiology and Pathophysiology,Faculty of Medicine, Collegium Medicum, Cardinal Stefan Wyszynski University in Warsaw, 01-938 Warsaw, Poland.
Introduction: In light of the current state of the law, it is not possible to invoke the conscience clause when providing pharmaceutical services, which includes the procedure for dispensing emergency contraception to a patient. Introduction of emergency contraception available withut prescription is associated with a necessity of creating safe procedures both for patients and pharmacists.
Aim Of The Study: The purpose of the study was to analyze the Polish and international legal regulation of the conscience clause issue and how to optimize the process of making emergency contraception available without a prescription.
Brain Spine
December 2024
Department of Gynecology, CHU de Liege, Liège, Belgium.
Introduction: Exogenous and endogenous sex hormones, especially Progesterone agonists, may be causally linked to meningioma progression. Cessation of treatment leads to stabilization or regression of Progestin-induced meningioma. In many cases, avoiding sex hormone therapy may be possible in the context of meningioma treatment.
View Article and Find Full Text PDFEstrogens are key hormones that play a vital role in the physiology of the reproductive system in women. However, their therapeutic use in hormonal treatment, contraception, and the treatment of hormone-dependent diseases may be associated with a number of side effects, especially on the liver. This article focuses on the mechanisms of action of estrogens and their potential hepatotoxic effects, as well as risk factors and possible differences between representatives.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!