A four-year study of clomiphene citrate challenge test results

Abstract

Objective: The aim of this study was to review our clomiphene citrate challenge test (CCCT) results to determine whether borderline or abnormal test results are an adequate basis for denying admittance into an In Vitro Fertilization (IVF) program. Design: A retrospective study of 84 patients, excluding donor egg and donor embryo recipients, having had a CCCT and having undergone one or more IVF cycles between 1997 and 2001. Materials and Methods: CCCT was performed according to the following clinic guidelines: 1) Serum Estradiol and follicle stimulating hormone (FSH) levels were obtained on the third day of menses. 2) On cycle day five Clomiphene Citrate (100mg) was administered daily for a total of five days. 3) On cycle day 10 another serum FSH level was obtained. Serum Estradiol and FSH levels were determined by Enzyme-linked fluorescent immunoassay (ELFA). An abnormal CCCT was defined as a FSH level above 10.0 mIu/ml on day three or day 10 and/or an Estradiol level greater than 60 pg/ml on day three. The test results were reviewed for each patient and compared to the number of eggs retrieved and the outcome of each cycle. Results: Eighty-four patients undergoing 114 IVF cycles were divided into two groups, normal CCCT and abnormal CCCT, and compared to establish a correlation between the test result and achieving a pregnancy with IVF. No significant difference was noted between the abnormal and normal CCCT groups for patients’ age (35, range 27–44 vs. 34, range 27–44), or average number of oocytes retrieved (10.6 vs 10.8). Five of the cycles were cancelled due to poor stimulation. Two of the five had a normal CCCT and three had an abnormal test. Sixty-four retrievals were performed in the abnormal group with 32 (50%) achieving a positive serum pregnancy test, 27 (42%) having at least one gestational sac, and 20 (31%) having a live birth. Patients with an abnormal result achieving pregnancy included FSH levels on day three and day 10 ranging from 1.0–25.8 mIu/ml and Estradiol levels on day three ranging from 10–282 pg/ml. It is interesting to note that ten of the 12 patients (83%), who had a positive serum pregnancy test but did not deliver, failed the Estradiol portion of the CCCT. Fifteen of the 32 (47%) who had negative serum pregnancy tests also failed the Estradiol portion of the test. The normal CCCT group consisted of 44 retrievals with 19 (43%) achieving a positive serum pregnancy test, 16 (36%) having at least one gestational sac, and 13 (29%) having a live birth. Chi square and T-test analysis does not show this data to be significantly different. Conclusion: The clomiphene citrate challenge test, when used with other deciding factors such as microfollicle count, previous stimulation response, etc., can be a useful tool in patient education in IVF cycles. Used alone the CCCT is not a desirable selection criteria for denying admittance into an IVF program. Despite indications of diminished ovarian reserve, fifty percent of the abnormal CCCT patient group achieved positive serum pregnancy levels. There does appear to be a correlation between patients who fail the Estradiol portion of the test and increased rate of miscarriage.