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Published on: July 5, 2024
Menstrual cycle synchronization, ovarian stimulation, and in vitro fertilization in olive baboons (Papio anubis): a
Atunga Nyachieo1, Carl Spiessens, Daniel C Chai
1Leuven University Fertility Centre, University Hospital Gasthuisberg, Leuven, Belgium.
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 1 (C1), 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 long GnRH agonist protocol for ovarian stimulation may be suitable for ovarian stimulation in baboons.