Seminal plasma inhibin-B level is a useful predictor of the success of conventional testicular sperm extraction in patients with non-obstructive azoospermia.

AIM: The value of serum inhibin-B as a predictor of the presence of testicular spermatozoa is still controversial. The purpose of this study is to evaluate the predictive value of the seminal plasma inhibin-B level, which might more directly reflect the secretion by Sertoli cells, and to discriminate between successful and failed testicular sperm extraction (TESE) in non-obstructive azoospermia. METHODS: Sixty-two patients with non-obstructive azoospermia were examined at the Department of Obstetrics and Gynecology at Niigata University Hospital, Niigata, Japan. The level of inhibin-B was measured using a two-site enzyme-linked immunoassay. RESULTS: Testicular sperm were successfully retrieved in 17 of 62 patients (27.4%). The serum levels of follicle-stimulating hormone (FSH) were significantly lower and the serum and seminal inhibin-B concentrations were significantly higher in the successful TESE group compared with the failed TESE group. According to the receiver operating characteristics (ROC) curve analysis, the best discriminating seminal plasma inhibin-B level was 27.0 pg/mL (sensitivity 88.2%, specificity 93.3%). The best discriminating serum inhibin-B level was 34.0 pg/mL (sensitivity 70.6%, specificity 95.6%). The area under the ROC curve for seminal plasma inhibin-B was significantly larger than that for FSH and testicular volume. Using multivariate logistic regression analysis, only seminal plasma inhibin-B was an independent predictor of the presence of spermatozoa on TESE. CONCLUSION: Seminal plasma inhibin-B level is a useful predictor of the presence of testicular sperm in men with non-obstructive azoospermia.

Effects of low-dose metformin in Japanese women with clomiphene-resistant polycystic ovary syndrome.

Background and Aims: The aim of the present prospective observational study was to evaluate the effects of low-dose, short-term metformin, in combination with clomiphene (CC), in CC-resistant infertile Japanese women with polycystic ovary syndrome (PCOS). Methods: Metformin therapy was administered orally (one 250 mg tablet, twice daily) to 15 CC-resistant infertile patients with PCOS, beginning on the third day of progestin-induced withdrawal bleeding, and was continued for 14 days in the first cycle. In the event of anovulation, 100 mg/day of CC was given during subsequent cycles on days 5-9, in addition to the aforementioned dose of metformin. Hormonal and metabolic parameters were measured on the second or third days of the first cycle and also the fourth cycle, following an overnight fast. Results: None of the 15 women successfully ovulated during the first cycle with metformin treatment alone. After two subsequent cycles with the combination of CC and metformin, ovulation was confirmed in 17 of 29 cycles (61%) and in 13 of 15 patients (87%). Two women became pregnant within 2 months of therapy (13%). There were no cases of ovarian hyperstimulation syndrome. Following three cycles of metformin therapy, a slight reduction in serum levels of luteinizing hormone (LH), free testosterone, androstenedione, dehydroepiandrosterone sulfate, hemoglobin A1c and total cholesterol was seen, while serum LH/follicle-stimulating hormone ratio and serum level of low-density lipoprotein cholesterol were significantly decreased. Although there were no significant differences between the responder (n = 11) and non-responder (n = 2) groups at baseline, the levels of plasma fasting insulin was significantly higher and fasting glucose/insulin ratio was significantly lower in the non-responder group compared with the responder group after three cycles. Conclusion: Low-dose, short-term metformin, combined with CC, can improve ovulation rates in CC-resistant infertile Japanese women with PCOS. (Reprod Med Biol 2004; 3: 19-26).