Faculty Bibliography

PURPOSE: To investigate production of progesterone's precursor, pregnenolone, in the early oocyte donation pregnancy. METHODS: Pregnenolone and progesterone were measured on luteal days 21, 28, 35, 60 and 80. Progesterone was measured via the Immulite system, pregnenolone by liquid chromatography separation with tandem mass spectrometric detection. RESULTS: Progesterone rose significantly from days 35 today 60. Pregnenolone likewise rose significantly from days 35-60, but at a much higher rate, with an increase of 57 % by day 60, 75 % to day 80. The increase in pregnenolone was statistically more significant than the increase in progesterone (p < .05). CONCLUSIONS: This is the first report describing that progesterone's precursor, pregnenolone, increases with time in the very early pregnancy. Because no corpus luteum is present in oocyte recipients, the main source of pregnenolone is the early placenta. Measurements of pregnenolone may provide information concerning early trophoblast function and may represent a method of assessing placental competency.

The timing of the luteoplacental shift has been eloquently studied,however there has been little new information brought forth on the subject over the past 2 decades. OD provides a unique model to study this phenomenon,as women who become pregnant do so in the absence of a CL.The timing of the LPS in oocyte recipients using changes in progesterone(Prog) levels can only be extrapolated because exogenous Prog is always given. Pregnenolone(Preg) is the Prog precursor made by the placenta and is without an exogenous source. Measurements of Preg may provide better information about the timing and even the quality of placental maturation. Methods.Recipients' serum was drawn on luteal days 21,28,35,60and80.Prog was measured using the Immulite system,an immunoassay utilizing polystyrene bead solid phase and a chemiluminescent substrate.The intra and inter assay imprecision is 7-10% and 9-12%. 50 delivered patients were selected, 36 of whom had Prog levels for all days listed. Stored frozen serum samples from 6 delivered DE recipients were used for the Preg analysis.This number was low due to the high cost of each test.Analysis was performed by Endocrine Sciences using liquid chromatography separation with tandem mass spectrometric detection (LC-MS/MS). An MDS-Sciex API5000 triple quadrupole mass spectrometer was used and quantification of analyte and standard was performed in selected reaction monitoring mode(SRM).The intra-day imprecision is 2-3%.Using random effects models to fit to the longitudinal data, the significant differences between Preg and Prog were evaluated. Results. Preg levels rise in the very early DE pregnancy, and this rise is significantly different from the changes in Prog(p<.05 linear mixed model). (Figure Presented) Box plots at individual days respect to their longitudinal measurements. Concl.These results provide valuable new information and ignite interest in further study of the developing placenta.Future work related to the timing and amplitude of this rise in pregnenolone c!

OBJECTIVE: To determine whether there is a difference in pregnancy outcomes, stratified by age, between women undergoing elective single blastocyst transfer (eSBT) versus those undergoing double blastocyst transfer (2BT). DESIGN: Retrospective analysis. SETTING: University IVF center. PATIENT(S): A total of 1,141 nondonor IVF cycles in women aged <40 years from January 2004-March 2007. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Eggs retrieved, embryos cryopreserved, implantation rates, clinical pregnancy rates (PR), live birth rates (LBR), spontaneous abortion rates (SAB). RESULT(S): Pregnancy outcomes in 52 cycles of women <40 years of age who underwent eSBT were compared with 1,086 cycles of women who underwent 2BT in fresh IVF cycles from January 2004-March 2007. Overall, the eSBT was associated with a statistically significant 92% reduction in the twinning rate (from 25%-2%) while maintaining a high clinical PR (63% in the eSBT group vs. 61% in the 2BT group). CONCLUSION(S): Women who are <40 years of age undergoing nondonor fresh IVF cycles can electively choose to transfer a single blastocyst for the purpose of significantly reducing their risk of multiples without compromising their PR