Menstrual cycle and cigarette smoking behavior.

Female cigarette smokers participated in daily two-hour sessions over at least two consecutive menstrual cycles. Automated measurements of each cigarette puff and its duration were recorded. Comparisons in these measurements were between premenstrual and menstrual portions and the rest of the cycle. Most of the subjects increased the mean number of cigarette puffs per session and/or the total puff duration per session during the menstrual phase of the cycles.