RT Journal Article SR Electronic T1 Delayed elimination of caffeine by women in the last 2 weeks of pregnancy JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP 377 OP 380 VO 127 IS 5 A1 W. D. Parsons A1 J. G. Pelletier YR 1982 UL http://www.cmaj.ca/content/127/5/377.abstract AB Caffeine elimination was studied in 15 women at 38 to 40 weeks' gestation. The mean hourly caffeine clearance, 37 ml/kg, determined from assays of saliva, was only 39% of the value previously reported for nonpregnant adults (94 ml/kg). Reassessment in four of the women 2 to 12 weeks post partum showed that in each woman the caffeine clearance had increased more than threefold and that the mean caffeine concentration in the saliva after no intake of caffeine for 24 hours was now much lower (0.07 v. 0.84 microgram/ml).