Reproductive performance was determined in GnRH (4 mug synthetic GnRH agonist, buserelin, receptal; n = 37) and saline (control, n = 38) treated (i.m.) does on day 12 post-mating during the breeding season. Kidding rate was higher in the GnRH treated group (87%) compared to the control (68%) group (P < 0.05). The does in the GnRH group had more twins (P < 0.01) and consequently a higher total number of kids born and a larger litter size was recorded. Administration of GnRH on day 12 post-mating did not affect birth weight of kids. In conclusion, GnRH administration improved the reproductive performance of goats when administered on day 12 post-mating although the financial implications need to be evaluated. (C) 2003 Elsevier B.V. All rights reserved.