Table 1: Behavioural indices in open field test for rats in proestrus, late dioestrus, and after progesterone withdrawal. All values . Late dioestrus (LD, ), proestrus (Pro, ), high progesterone (HP, ).


Total distance travelled (cm)
Average speed ( )
Time in central zone (%)
Time in middle zone (%)
Time in outer zone (%)
Number of central zone re-entries
Time rearing (%)
Time freezing (%) n/a
Time grooming (%)