GnRH Agonist Stimulation Test Research Articles

Possibilities and Limits of Ovarian Reserve Testing in ART

Markers of ovarian reserve are associated with ovarian aging as they decline with chronologic age, and hence may predict stages of reproductive aging including the menopause transition. Assessment of ovarian reserve include measurement of serum follicle stimulating hormone (FSH), anti-M�llerian hormone (AMH), and inhibin-B. Ultrasound determination of antral follicle count (AFC), ovarian vascularity and ovarian volume also can have a role. The clomiphene citrate challenge test (CCCT), exogenous FSH ovarian reserve test (EFORT), and GnRH-agonist stimulation test (GAST) are dynamic methods that have been used in the past to assess ovarian reserve. In infertile women, ovarian reserve markers can be used to predict low and high oocyte yield and treatment failure in women undergoing in vitro fertilization. However the markers may have limitations when an in depth analysis of their accuracy, cost, convenience, and utility is performed. As ovarian reserve markers may permit the identification of both the extremes of ovarian stimulation, a possible role for their measurement may be in the individualization of treatment strategies in order to reduce the clinical risk of ART along with optimized treatment burden. It is fundamental to clarify the cost/benefit of its use in the ovarian reserve testing before initiation of an IVF cycle and whether the ovarian reserve markers-determined strategy of ovarian stimulation for assisted conception may be associated to improved live birth rate.

Evaluation of GnRH analogue testing in diagnosis and management of children with pubertal disorders

Context:Gonadotrophin releasing hormone (GnRH) stimulation test is pivotal in the assessment of children with pubertal disorders. However, lack of availability and high cost often result in the test falling into disfavor. We routinely use the GnRH analogue stimulation test as an alternative at our center.Aim:To present the data on children with endocrine disorders who underwent GnRH agonist stimulation test in pediatric endocrine clinic of a tertiary care referral hospital.Setting and Design:Pediatric endocrine clinic of a tertiary care referral hospital. Retrospective analysis of case records.Materials and Methods:The details pertaining to clinical and radiological parameters and hormonal tests were retrieved from case records of 15 children who underwent GnRH agonist stimulation test from May 2010 to April 2011.Results:Indications for testing with GnRH analogue were evaluation of delayed puberty, diagnosis of precocious puberty, assessment of hormonal suppression in treatment of precocious puberty and micropenis in two, nine, three and one cases, respectively. The results of the test and clinical and radiological parameters were in concordance. The test was also crucial in diagnosing the onset of central precocious puberty in two children with congenital adrenal hyperplasia.Conclusion:GnRH agonist test is a convenient, safe test that can be performed on an out-patient basis and can help the clinicians in the correct diagnosis and appropriate treatment of various puberty-related disorders.

Use of letrozole challenge test to adjust gonadotropin dose in non–down-regulated cycles

The use of a letrozole challenge test to predict ovarian response is described. The authors show that a ratio of cycle day 7 to cycle day 3 post-letrozole FSH level >1.5 is associated with poor ovarian response.

Assessment of theca cell function prior to controlled ovarian stimulation: the predictive value of serum basal/stimulated steroid levels

Serum androgen levels correlate with ovarian sensitivity to follicle-stimulating hormone (FSH) but in practice, standard baseline serum testosterone (T) levels prior to in-vitro fertilization (IVF) may not be the most appropriate marker for determination. Infertile women enrolled in an IVF programme were included in this study. Serum T and Delta4-androstenedione (A), and the androgen precursor 17-hydroxyprogesterone (17-OHP) were measured before and 24 h after a gonadotrophin-releasing hormone agonist stimulation test (GAST). An early follicular phase antral follicle count (AFC) was also performed. Patients were subsequently enrolled in a long gonadotrophin-releasing hormone agonist protocol with a standard FSH dose (150 IU) for 7 days to assess the association between androgen levels and ovarian responsiveness to FSH. The GAST elicited a significant increase in serum androgen levels that was well correlated with AFC. 17-OHP showed the greatest response to GAST and strongest correlation with AFC. The 17-OHP response to GAST differentiated patients with high ovarian reserve (OR) from those with low or normal OR as assessed by AFC, whereas only the estradiol response could differentiate those with low AFC. GAST-stimulated serum levels of 17-OHP were also correlated with ovarian response to FSH. Using receiver operating characteristic curve analysis, stimulated 17-OHP levels were predictive of the ovarian response to controlled ovarian stimulation, with similar power to that observed with AFC but lower power than with anti-Müllerian hormone. Serum androgen levels following GAST are correlated with AFC and ovarian response to FSH. Serum T is a less sensitive marker of theca cell function than 17-OHP.

Dynamic tests of ovarian reserve: a systematic review of diagnostic accuracy

Despite a plethora of tests of ovarian reserve, there is no perfect test to predict pregnancy. Recent evidence points that anti-Müllerian hormone and antral follicle count may be better than other tests, although other tests continue to be used and form the basis of exclusion of women from fertility treatments. This systematic review concentrated on dynamic tests of ovarian reserve [clomifene citrate challenge test (CCCT), gonadotrophin-releasing hormone agonist stimulation test (GAST) and exogenous FSH ovarian reserve test (EFORT)] and assessed their predictability in terms of fertility outcomes. The study did not restrict itself to women undergoing IVF. The diagnostic odds of abnormal CCCT for non-pregnancy were 2.11 (95% confidence interval, 1.04-4.29) at FSH >10 IU/l (day 3 or 10). The diagnostic accuracy of GAST and EFORT could not be determined due to inconsistencies in the way these tests were conducted. This systematic review and meta-analysis was limited by heterogeneity in terms of the population sampled and the index and reference tests. There is an urgent need for consensus on the performance of these tests and the definition of normality, if their use is to be continued. However, given the present level of evidence, these tests should be completely abandoned.

Single and Repeated GnRH Agonist Stimulation Tests Compared With Basal Markers of Ovarian Reserve in the Prediction of Outcome in IVF

To study the value of a single or repeated GnRH agonist stimulation test (GAST) in predicting outcome in IVF compared to basal ovarian reserve tests. A total of 57 women was included. In a cycle prior to the IVF treatment, on day 3, an antral follicle count (AFC) was performed and blood taken for basal FSH, inhibin B and E2 measurements, followed by a subcutaneous injection of 100 microg triptorelin for the purpose of the GAST. Twenty-four hours later blood sampling was repeated. All the tests were repeated in a subsequent cycle. From the GAST E2 and inhibin B response were used as test parameters. The outcome measures were poor ovarian response and ongoing pregnancy. Group comparisons were done using the Mann-Whitney or chi-square test. Univariate and multivariate logistic regression was applied to assess which test revealed the highest predictive accuracy as expressed in the area under receiver-operating characteristic curve (ROC(AUC)). Clinical value was compared by calculating classical test characteristics for the best logistic models. All the basal and GAST variables were significantly different in the poor responders (n = 19) compared to normal responders (n = 38). In the univariate analysis on cycle 1 tests the AFC was the best predictor for poor ovarian response, while in cycle 2 the E2 response in the GAST performed best (ROC(AUC) of 0.91 for both). Multivariate analysis of the basal variables led to the selection of AFC and inhibin B in cycle 1, yielding a ROC(AUC) of 0.96. Mean E2 response was selected in a multivariate analysis of the repeated GAST variables (ROC(AUC) 0.91). At a specificity level of -0.90, several logistic models including GAST variables appeared to have a sensitivity (-0.80), positive predictive value (-0.82) and false positive rate (-0.18), comparable to a logistic model containing AFC and inhibin B. None of the test variables showed a significant relation with ongoing pregnancy. The GAST has a rather good ability to predict poor response in IVF. However, comparing the predictive accuracy and clinical value of the GAST with a day 3 AFC and inhibin B, it appeared that neither a single nor a repeated GAST performed better. In addition, the predictive ability towards ongoing pregnancy is poor. Therefore, the use of the GAST as a predictor of outcome in IVF should not be advocated.

Age = egg quality, FSH level = egg quantity

For centuries, it has been clear that fertility declines dramatically as women age beyond their mid-thirties, with only rare pregnancies beyond age 45. In the past 10 years, markers of ovarian reserve in infertile patients have also been shown to strongly influence the potential for pregnancy and have come to guide the approach to diagnosis and treatment. These markers have included assessments of FSH, LH, estradiol, and inhibin in the early follicular (“basal”) phase and after ovarian stimulation (with a clomiphene citrate challenge test or GnRH agonist stimulation test, for example).

Serum anti-Müllerian hormone levels: a novel measure of ovarian reserve.

Anti-Müllerian hormone (AMH) is produced by the granulosa cells of preantral and small antral follicles and its levels can be assessed in serum. Since the number of ovarian follicles declines with increasing age, AMH levels might be used as a marker for ovarian ageing. Therefore, we studied the relationship between AMH levels and ovarian response during ovarian stimulation for IVF. A total of 130 patients undergoing their first IVF treatment cycle using a long protocol with GnRH agonist was prospectively included. Blood withdrawal was performed and the number of antral follicles was assessed by ultrasound on day 3 of a spontaneous cycle. Poor response and the number of oocytes were used as primary outcome measures. In a random subset of 23 patients a GnRH agonist stimulation test was performed to investigate whether a rise in FSH and LH would affect AMH levels. The data of 119 patients were analysed. Serum AMH levels were highly correlated with the number of antral follicles (r = 0.77; P < 0.01) and the number of oocytes retrieved (r = 0.57, P < 0.01). A negative association was found between AMH levels and poor ovarian response (fewer than 4 oocytes or cycle cancellation; OR 0.82, 95% CI 0.75-0.90, P < 0.01). Inclusion of inhibin B and FSH concentrations to AMH in a multivariate model improved the prediction of ovarian response. The post GnRH agonist rise in FSH and LH levels did not influence AMH values. Poor response in IVF, indicative of a diminished ovarian reserve, is associated with reduced baseline serum AMH concentrations. In line with recent observations it appears that AMH can be used as a marker for ovarian ageing.

Prediction of over-response to ovarian stimulation in an intrauterine insemination programme.

Prediction of poor-response is of equal importance to prediction of over-response in intrauterine insemination programmes. The gonadotrophin-releasing hormone agonist (GnRHa) stimulation test (GAST) was assessed as a predictor of over-response to ovarian stimulation in 81 patients. Blood samples were taken on cycle day 2 (before and 24 h after starting the GnRHa). Day 2 and 3 samples were assayed for oestradiol, follicle stimulating hormone (FSH) and luteinizing hormone (LH). Linear and logistic regression analyses were used to assess age, day 2 FSH, day 2 FSH/LH, oestradiol ratio (oestradiol on day 3/oestradiol on day 2) and FSH ratio (FSH on day 3/FSH on day 2) as predictors of the number of follicles (total and > or = 14 mm), oestradiol on HCG day, and clinical pregnancy rate as appropriate. Several parameters were also compared between the patients who produced < or = 3 (> or = 14 mm) follicles (group A) and those who produced >3 (> or = 14 mm) follicles (group B). The mean +/- SEM age of the patients in the study was 32 +/- 0.4 years. The mean total dose of recombinant FSH was 800 +/- 20 IU and the mean duration of stimulation was 7.6 +/- 0.2 days. Nine (11%) and 12 (15%) patients were cancelled for poor and over-response respectively. The oestradiol ratio was significantly positively correlated with oestradiol on HCG day (P < 0.001), and with the number of mature follicles (> or = 14 mm) (P = 0.01). Age, day 2 FSH and FSH ratio were not significantly correlated with oestradiol on HCG day, total follicles and follicles > or = 14 mm. None of the above-mentioned variables was correlated with clinical pregnancy rate. Group A had significantly lower oestradiol ratio (P = 0.007), longer duration of stimulation (P = 0.002), higher total FSH dose (P = 0.001), and lower oestradiol on HCG day (P = 0.001). GAST is therefore useful in predicting the high responders to gonadotrophin stimulation.

Accuracy of ovarian reserve tests.

Several tests predict ovarian reserve in women undergoing assisted reproductive technologies. However, the accuracy of these tests in assessing the number of the remaining follicles within the ovary (ovarian reserve) has not been previously validated. The aim of this study was to assess the accuracy of ovarian reserve tests, namely basal and clomiphene-stimulated follicle stimulating hormone (FSH) concentrations and gonadotrophin-releasing hormone (GnRH) agonist stimulation test in predicting the number of the follicles within the ovaries. The ovaries of 22 parous women over 35 years of age who underwent oophorectomy were examined histologically for follicle number. Early follicular phase serum FSH, clomiphene citrate challenge tests (CCCT) and GnRH agonist stimulation test (GAST) were performed in the menstrual cycle prior to the surgery. The predictive value of these tests was then assessed. A positive correlation was detected between basal serum oestradiol concentrations and follicles per unit tissue but no significant correlation was detected between basal and clomiphene-stimulated FSH and follicles per unit tissue. The receiver operator characteristic curves indicated that the clomiphene citrate challenge test was the most accurate of the three tests assessed. In conclusion, none of the tests in this study accurately reflects ovarian reserve.

Ovarian reserve tests in infertility practice and normal fertile women

The decline in fecundity with the age of the woman is mainly attributed to the loss of follicles from the ovary and a decrease in oocyte quality. Evaluation of the aging status of the ovary in an individual woman has been hampered by a lack of knowledge with regard to the relative contribution of these two factors. Most if not all so called ovarian reserve tests (ORT) reflect indirectly the remaining follicle pool in the ovary. Direct a priori assessment of oocyte quality is not possible to date. In this section the predictive value of several ovarian reserve tests for the outcome of fertility treatment is listed and commented. In addition, the study of several of the ORTs in normal, fertile women is described. From the data presented dynamic testing of the ovarian function by the clomiphene citrate and GnRH agonist stimulation test, as well as static testing by the use of ultrasound based antral follicle counts seem to offer the highest clinical value. Studies performing direct comparison of these tests are needed, as well as analysis of the way these tests should direct decision making in infertility diagnosis and treatment.

Endocrinology: Ovarian reserve test with the gonadotrophin-releasing hormone agonist buserelin: correlation with in-vitro fertilization outcome

A gonadotrophin-releasing hormone agonist stimulation test determination of follicle stimulating hormone (FSH) concentrations before and 2 h after buserelin injection was carried out in 78 in-vitro fertilization cycles, and compared with basal FSH concentrations to predict ovarian response. Ovarian response was quantified by the ratio of peak oestradiol concentration divided by the total dose of human menopausal gonadotrophin (HMG) administered, the most reproducible parameter in 11 patients who underwent two treatment cycles. Stimulation outcome was highly related to the buserelin test, the best prognostic indicator being the sum of FSH concentrations. However, basal FSH concentration achieved similar correlations, even in those patients aged > 35 years. Sensitivity, specificity, positive and negative predictive values of basal FSH concentration and sum of FSH concentrations were similar. Low basal concentration and sum of FSH concentrations were both associated with a better ovarian response. Construction of receiver operator characteristic curves demonstrated that basal FSH concentration was more informative than the sum of FSH concentrations. Finally, the sum of FSH concentrations did not increase the prediction of ovarian response variability. We conclude that the buserelin test is strongly predictive of stimulation outcome, but is no more informative than the usual screening. We suggest that the performance of other stimulation tests should be clearly compared with that of basal FSH concentration.