Tobacco Smoke and Pregnancy: Segmental Analysis of Nicotine in Maternal Hair

Abstract

The investigation assessed nicotine metabolism prior to and during pregnancy in relation to different maternal smoking habits. It included segmental hair analysis in 3 groups of postpartum women: 32 active smokers, 35 passive smokers, and 19 unexposed nonsmokers. Maternal hair at least 12 cm long was collected after delivery and was divided into four 3-cm-long segments representing each trimester of pregnancy and the 3 months prior to pregnancy. Hair nicotine concentration was determined by gas chromatography-mass spectrometry. Nicotine levels were the highest in the 3-month period before pregnancy and it gradually decreased with advancing gestation in all study groups. These results suggest that when assessing tobacco exposure as measured by nicotine in hair, metabolic changes of nicotine during pregnancy should be taken into consideration.

Changes in the rate of nicotine metabolism across pregnancy: a longitudinal study

“…A total of 79 (78%) women provided more than one sample for comparison and 26 (26%) women provided a sample at all five time-points. The median (IQR) number of cigarettes participants smoked at each time-point was: 8-14 weeks, 10 (5-10); 18-22 weeks, 10 (4-11); 32-36 weeks, 10 (5-10); 4 weeks postpartum, 10 (7.5-15); and 12 weeks postpartum, 10 (7)(8)(9)(10)(11)(12)(13)(14)(15). Two participants who provided follow-up samples reported to have used NRT.…”

“…The difference between 8-14 weeks' gestation and 12 weeks postpartum was in the same direction, but was not significant after allowing for multiple testing; low statistical power may have contributed to this finding. Studies which have been able to derive longitudinal trends during pregnancy have relied upon the analysis of hair samples which cannot provide measurement at precise time-points, and may be problematic due to contamination from hair products or passive smoking [6,7].…”

“…Nicotine replacement therapy (NRT) is often provided to assist pregnant women to stop smoking, yet despite its effectiveness in nonpregnant populations, NRT has not been found in randomized controlled trials to be effective in pregnancy, except possibly in the short term [2,3]. A potential reason for this may be that nicotine metabolism is increased during pregnancy [4][5][6][7]. It is possible that the dose of nicotine in NRT may not be enough to reduce cigarette cravings adequately.…”

Incorporation of Drug and Substances in Hair

“…Diğer taraftan yapılan bazı çalışma-larda, vücutta bulunan madde miktarıyla saçtaki biriken arasında her zaman pozitif korelasyon olmadığı gözlemlenerek pasif difüzyon modeline karşı çıkılmıştır. [5][6][7] Bu değişkenliklerin ise denekler arasındaki farmakokinetik farklılıklardan kaynaklanabileceği düşünülmüştür. 6 Yine pasif difüzyon modelinin sorgulandığı diğer bulgu ise saç-taki ana ilaçla metaboliti arasındaki oranlara ilişkin elde edilen sonuçlardır.…”

“…47 Bazı çalışmalarda, nikotin ve kotinin yenidoğanların saçında saptanmıştır. 7,8 Kırık anne/bebek çifti üzerinde yapılan araştırmada, sırasıyla yenidoğan ve annenin saçlarında nikotin konsantrasyonları 0,15-11,8 ve 0,37-63,5 ng/mg olarak bulunmuştur. 44 Bu çalışma, yenidoğan ve annenin saçındaki nikotin konsantrasyonu arasında istatistiksel olarak anlamlı korelasyon bulunduğu göster-miştir.…”