The impact of the menstrual cycle and hormonal contraceptives on competitiveness

► Is competitiveness in women influenced by hormones? ► We use the menstrual cycle and contraceptive intake as proxies for hormonal fluctuations. ► Subjects can choose between a competitive and a non-competitive payment scheme for an arithmetic task. ► The likelihood of selecting into the competitive scheme varies strongly over menstrual cycle and with intake of hormonal contraceptives. ► The observed patterns are consistent with a negative impact of progesterone on competitiveness.