Menstrual cycle synchronization, ovarian stimulation, and in vitro fertilization in olive baboons (Papio anubis): a prospective randomized study

Objective: To synchronize the baboon menstrual cycle and to compare different methods of ovarian stimulation for IVF in baboons. Design: Prospective randomized study. Setting: Institute of Primate Research, Nairobi, Kenya. Animal(s): Ten female baboons were treated with an oral contraceptive (33 8 days) and randomized for ovarian stimulation in two cycles. Intervention(s): In cycle I (Cl), baboons were stimulated as follows: clomiphene citrate (CC) for 5 days followed by antagonist (group CC-1, n = 3); recombinant gonadotropins (rGn: rFSH and rLH) with antagonist (group antagon-1, n = 3); and long GnRH agonist protocol (group LP-1, n = 4). After 1- month rest, in cycle 2 (C2), the baboons were stimulated as follows: CC for 8 days without antagonist (group CC-2, n = 2); short GnRH agonist protocol (group SP-2. n = 4); long GnRH agonist protocol (group LP-2, n = 4). Oocyte aspiration was performed 34-36 hours after injecting 5000 IU recombinant hCG; the oocytes were then fertilized. Main Outcome Measure(s): Oocytes retrieved and fertilization rate. Result(s): Withdrawal bleeding occurred 4 +/- 1 days after the cessation of the contraceptive. Ovarian stimulation using the different protocols resulted in the following mean numbers of retrieved oocytes: LP-1, n = 19; LP-2, n 19; CC-1, n = 4; CC-2, n = 4; antagon-1, n = 9; and SP-2, n = 14. Fertilization by intracytoplasmic sperm injection varied (23%-54%). Conclusion(S): The baboon menstrual cycle can be synchronized using an oral contraceptive. A Iona GnRH agonist protocol for ovarian stimulation may be suitable for ovarian stimulation in baboons. (Fertil Steril(R) 2009;91:602-10. (C)2009 by American Society for Reproductive Medicine.)