TY - JOUR
T1 - Steroid reduction during ovarian stimulation impairs oocyte fertilization, but not folliculogenesis, in rhesus monkeys
AU - Zelinski-Wooten, M. B.
AU - Hess, D. L.
AU - Wolf, D. P.
AU - Stouffer, R. L.
N1 - Funding Information:
Received September 21, 1993; revised and accepted February 15,1994. * Supported by National Institutes of Health grants HD-20869 (to R.L.S.), HD-18185 (to In Vitro Fertilization-Experimental Embryology and Hormone Assay Core Laboratories), and RR-00163, Bethesda, Maryland. Oregon Regional Primate Research Center publication 1921. t General Program Prize Paper presented at the 48th Annual Meeting of The American Fertility Society, New Orleans, Louisiana, November 2 to 5, 1992.
PY - 1994
Y1 - 1994
N2 - Objective: To test the hypothesis that steroids locally modulate and may be required for normal follicular function and gametogenesis in primates, the effects of steroid reduction during gonadotropin-stimulated folliculogenesis was studied in rhesus monkeys. Design: Animals received human FSH (hFSH; days 1 to 6) and hFSH + human LH (hLH; day 7) to promote multiple follicular growth, and then received hCG (day 8) for ovulatory maturation. Four animals received trilostane (3β-hydroxysteroid dehydrogenase inhibitor) on days 1 to 8 or no inhibitor (controls; n = 4). Follicles were aspirated 34 hours after hCG. Main Outcome Measures: Follicular growth, serum E2, P, and pregnenolone, oocyte nuclear maturity, and IVF. Results: Trilostane markedly reduced E2 to levels as low as 7% of controls throughout the follicular phase. Pregnenolone was 66 fold greater during trilostane treatment relative to controls. In both groups, P was at baseline during follicular stimulation but was reduced for 72 hours after hCG in trilostane-treated animals. Despite E2 suppression, follicular growth and oocyte nuclear maturity were unaltered by trilostane. Trilostane hindered the fertilizability of metaphase II oocytes (15%) in three of four animals compared with controls (65%). Metaphase I oocytes that required >8 hours to complete meiosis in vitro failed to fertilize in the same three of four receiving trilostane relative to controls (31%). Conclusions: Follicular growth and oocyte meiosis did not require high or increasing E2 levels. Levels of follicular products other than E2 may be of value in determining the progress of ovarian stimulation protocols. However, the acquisition of oocyte competence for fertilization may require steroids.
AB - Objective: To test the hypothesis that steroids locally modulate and may be required for normal follicular function and gametogenesis in primates, the effects of steroid reduction during gonadotropin-stimulated folliculogenesis was studied in rhesus monkeys. Design: Animals received human FSH (hFSH; days 1 to 6) and hFSH + human LH (hLH; day 7) to promote multiple follicular growth, and then received hCG (day 8) for ovulatory maturation. Four animals received trilostane (3β-hydroxysteroid dehydrogenase inhibitor) on days 1 to 8 or no inhibitor (controls; n = 4). Follicles were aspirated 34 hours after hCG. Main Outcome Measures: Follicular growth, serum E2, P, and pregnenolone, oocyte nuclear maturity, and IVF. Results: Trilostane markedly reduced E2 to levels as low as 7% of controls throughout the follicular phase. Pregnenolone was 66 fold greater during trilostane treatment relative to controls. In both groups, P was at baseline during follicular stimulation but was reduced for 72 hours after hCG in trilostane-treated animals. Despite E2 suppression, follicular growth and oocyte nuclear maturity were unaltered by trilostane. Trilostane hindered the fertilizability of metaphase II oocytes (15%) in three of four animals compared with controls (65%). Metaphase I oocytes that required >8 hours to complete meiosis in vitro failed to fertilize in the same three of four receiving trilostane relative to controls (31%). Conclusions: Follicular growth and oocyte meiosis did not require high or increasing E2 levels. Levels of follicular products other than E2 may be of value in determining the progress of ovarian stimulation protocols. However, the acquisition of oocyte competence for fertilization may require steroids.
KW - Follicular stimulation
KW - IVF
KW - oocyte maturation
KW - rhesus monkeys
KW - steroid reduction during folliculogenesis
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U2 - 10.1016/s0015-0282(16)56771-5
DO - 10.1016/s0015-0282(16)56771-5
M3 - Article
C2 - 8194632
AN - SCOPUS:0028339798
SN - 0015-0282
VL - 61
SP - 1147
EP - 1155
JO - Fertility and sterility
JF - Fertility and sterility
IS - 6
ER -