Is chemiluminescent immunoassay an appropriate substitution for radioimmunoassay in monitoring estradiol levels?

Quantification of neurosteroids during pregnancy using selective ion monitoring mass spectrometry

Analytical techniques used to quantify neurosteroids in biological samples are often compromised by non-specificity and limited dynamic range which can result in erroneous results. A relatively rapid and inexpensive gas chromatography-mass spectrometry (GC-MS) was developed to simultaneously measure nine neurosteroids, including allopregnanolone, estradiol, and progesterone, as well as 25-hydroxy-vitamin D3 in plasma samples collected from adult women subjects during and after pregnancy. Sample preparation involved solid-phase extraction and derivatization, followed by automated injection on a GC equipped with a mass selective detector (MSD) operated in single ion monitoring (SIM) mode to yield a run time of less than 11min. Method detection limits for all neurosteroids ranged from 30 to 200pg/mL (parts per trillion), with coefficients of variation that ranged from 3% to 5% based on intra-assay comparisons run in triplicate. Although concentrations of estradiol measured by chemiluminescent immunoassay (CIA) were consistent with values determined by GC-MS values, CIA yielded considerable higher values of progesterone, suggesting antibody cross reactions resulting from low specificity. Mean neurosteroid levels and representative time-course data demonstrate the ability of the method to quantify changes in multiple neurosteroids during pregnancy, including rapid declines in neurosteroid levels associated with delivery. This simplified GC-MS method holds particular promise for research and clinical laboratories that require simultaneous quantification of multiple neurosteroids, but lack the resources and expertise to support advanced liquid chromatography-tandem mass spectrometry facilities.

Short coasting of 1 or 2 days by withholding both gonadotropins and gonadotropin-releasing hormone agonist prevents ovarian hyperstimulation syndrome without compromising the outcome

OBJECTIVE

To evaluate the effect of short coasting, by withdrawing both gonadotropins and gonadotropin-releasing hormone (GnRH) agonist, on the prevention of severe ovarian hyperstimulation syndrome (OHSS) without compromising pregnancy outcome.

DESIGN

Retrospective study.

SETTING

Large urban medical center.

PATIENT(S)

Forty-four women who had been coasted during controlled ovarian hyperstimulation (COH) for in vitro fertilization (IVF).

INTERVENTION(S)

When >or=20 follicles >15 mm with serum estradiol (E(2)) level of 4000 pg/mL were detected, both gonadotropins and GnRH agonist were withheld for 1 to 2 days.

MAIN OUTCOME MEASURE(S)

Changes of serum E(2) levels, number of oocytes retrieved, pregnancy rate.

RESULT(S)

The mean serum E(2) level fell from 7915 pg/mL at the onset of coasting to 3908 pg/mL on the day of human chorionic gonadotropin (hCG) administration. The mean number of oocytes retrieved and fertilization rate were 17.2% and 75.0%, respectively. Eighteen patients became pregnant (43.9%), and the implantation rate was 12.7%. Twenty-eight patients were coasted for 1 day, and 13 were coasted for 2 days. The mean decrease rate of serum E(2) level was 45.3% in 1-day coasting and 26.4% (first day) and 75.3% (second day) in 2-day coasting. The pregnancy outcome was similar between both groups. After coasting, three mild and two severe cases of OHSS occurred.

CONCLUSION(S)

Coasting for 1 or 2 days can be used successfully to prevent OHSS without compromising IVF cycle outcome.

Premature LH and progesterone rise in intrauterine insemination cycles: analysis of related factors

Premature LH and progesterone surges are associated with different factors and hormonal modulators. The aim of the present study was (i) to investigate the clinical and laboratory factors and (ii) to highlight the importance of different stimulation protocols in associated premature LH and progesterone surges in intrauterine insemination (IUI) cycles. The study involved a retrospective investigation of 75 patients undergoing IUI for infertility treatment (135 IUI cycles) between 1996 and 2000, with initial serum LH concentrations >10 mIU/ml during ovarian stimulation. Ultrasound characteristics, follicular sizes, serum oestradiol, progesterone and LH concentrations and ovarian stimulation protocols were measured. There was a wide range of oestradiol serum concentrations (93-2245 pg/ml) and follicular size (12-25 mm). In 49.6% of cycles, the dominant follicle was <16.5 mm. Patients with >2 follicles measuring <15 mm had higher oestradiol serum concentrations (P = 0.008). Multiple regression analyses revealed no association between these variables and premature LH/progesterone surge. In conclusion, LH/progesterone surges cannot be predicted utilizing clinical parameters normally employed, e.g. ultrasound serum oestradiol assay or ovarian stimulation protocol. Patients with follicles >14 mm or more and with high numbers of small follicles and high oestradiol are at risk of a spontaneous LH surge. These variables can be used to time the administration of GnRH antagonist administration until better predictive factors are demonstrated.