Biochemical verification of smoking status in pregnant and recently postpartum women.

Abstract

The present study was conducted to examine several different methods and cutpoints for determining smoking status in pregnant and recently postpartum women. Self-reported smoking status, urine cotinine levels determined by gas chromatography (GC) and by enzyme immunoassay testing (EMIT), and breath carbon monoxide (CO) levels were assessed at 28 weeks antepartum and 12 and 24 weeks postpartum in 131 women enrolled in studies on smoking cessation and relapse prevention. Classifications based on urine-cotinine GC testing served as the standard in most analyses. Overall agreement between self-reported smoking status and classification based on urine-cotinine GC testing was excellent (> or =95%) at several cutpoints (50, 25, and 12.5 ng/ml) but highest at 25 ng/ml. Classifications based on EMIT urine cotinine levels were in nearly perfect (> or =98%) agreement with those made by GC when the cutpoint for the former was set at approximately 80 ng/ml (79-87 ng/ml). Classifications based on breath CO were in relatively poor agreement (< or =87%) with GC classifications at all cutpoints examined but best at 4 ppm. Overall, these results provide detailed information on several commonly used methods for classifying smoking in pregnant and recently postpartum women that should be practically useful to researchers and clinicians involved in efforts to eliminate smoking in this population.

Detection of Cotinine in Newborn Dried Blood Spots

“…Although these data are collected without regard to later cancer, maternal smoking is substantially misclassified on birth certificates (18), which would attenuate relative risks. The remainder of case-control studies of childhood cancers have collected smoking data by maternal interview, raising the possibility of differential reporting between cases and controls, both due to the social disapproval of smoking while pregnant and feelings of culpability among mothers of cases (19). The results of our pilot study suggest that some of these issues may be circumvented by examining the tobacco-specific biomarker cotinine in DBS obtained during the neonatal period and retrieved from storage.…”

Prevalencia de tabaquismo durante el embarazo y factores asociados en Andalucía 2007-2012 (*)

“…Las referencias disponibles sobre cotinina urinaria proponen un punto de corte próximo a 80 ng/ml 35 . No obstante, Greaves 36 hace notar que los límites establecidos en la literatura dan lugar a una "zona gris" o de confusión en la que resulta difí-cil interpretar el estatus de fumadora, sobre todo en lo que se refiere a la exposición pasiva o al consumo esporádico.…”

Smoking in Moderate/Severe Preeclampsia Worsens Pregnancy Outcome, but Smoking Cessation Limits the Damage

“…However, a recent study of pregnant and postpartum women reported excellent agreement between self-reported smoking status and urinary cotinine measurement. 33 This would fit with the clear dose-related change in the risk of various outcomes from women who had never smoked, those who used to smoke but gave up, and those who smoked throughout their pregnancy reported here. This is encouraging and provides a further reason for pregnant women to stop smoking.…”