Twenty-five female volunteers were tested over three menstrual cycles: thirteen with spontaneous cycles and eleven using oral contraceptives. Menstrual-cycle-related changes in oestrogen and progesterone were expected to affect performance on various cognitive tests. Additionally, exposure to beliefs and research about menstrual- cycle effects was expected to increase motivation arising from a perceived disadvantage at certain stages - resulting in better perform­ ance in these phases. Subjects were tested on days l2(high oestrogen),23 (high oestrogen and progesterone) and 28/l (low oestrogen and progesterone), over three consecutive cycles. Daily basal body temperature records were taken by all subjects in cycle land through­ out the testing period for ovulatory subjects. An "educational input” was given to 11 subjects prior to second cycle testing.

Rod and Frame Test gave significant results in the predicted direction - poor performance Day l2 1 better Day 23 and average Day 28/1. The other tests did not show any significant results although there was a similar trend on the Group Embedded Figures Test although non­ significant. No difference was found between pill takers' and non-pill takers’ performance; nor between those receiving an educational input and those not. Contrary to Broverman's (1981) results, proximity to thermal nadir and peak was not found to be a significant factor in achieving significant results.

The results appear to be only partially explained by the oestrogen­ induced impairments of inhibition based perceptual disembedding ability. It is possible that expectations do influence performance level directly or indirectly although there is no support of this from the present research.