A controlled study was conducted to evaluate chronological relationship between oestrus onset, time of LH surge and ovulation time in does synchronized with Fluorogestone with different doses of pregnant mare serum gonadotropin (PMSG). For the purpose of the study, a total of 90 desert goats were used in this experiment. All does were treated with impregnated vaginal sponge containing 45 mg Chronogest. Upon sponge removal, animals were divided randomly into 3 groups (A, B, and C) and assigned to different PMSG doses (group A, 300 IU, group B, 500 IU and group C, 700 IU). There were no significant differences (P>0.05) between the treatment groups for the onset of oestrus or oestrous duration. Ovulation was occurred 54 hours post removal (HPR) in group A and 48 HPR in group B and C. LH surge reached 28 hours post removal, irrespective of the treatment. The chronological relationship between ovulation and oestrous onset was significantly longer in group A compared with group B and C. The time taken from LH surge to ovulation was significantly longer in group A (25.5 hours) compared with group B and C (19.7 and 19.8 hours, respectively). There was no significant difference in the time taken from LH surge to ovulation in group B and C. These results imply that the increasing doses of PMSG, following a 12 day treatment with intravaginal sponges significantly affect the ovulation time and chronological data in desert goats.