The role of inhibin B in prediction of in vitro fertilization or intracytoplasmic sperm injection cycles' outcome

OBJECTIVE: To investigate the usefulness of inhibin B concentrations obtained on the fifth day in predicting ovarian response and assisted reproductive technologies outcome.

METHODS: In this prospective multi-center study, infertile women who were candidate for in vitro fertilization or intracytoplasmic sperm injection for the first time were enrolled. These patients were referred to the Royan Institute, Vali-Asr Hospital and Alvand Hospital, Tehran, Iran between 2003 and 2004. The inclusion criteria were female age (20-35 years), body mass index (BMI) of 20-28 Kg/m2, duration of infertility >2 years, a normal menstrual cycle and a normal day 3 follicle stimulating hormone level of <8.5 IU/l. All patients underwent long standard gonadotrophin releasing hormone agonist protocol. Plasma level of inhibin B was checked on the fifth day of menstrual cycle. The diagnostic accuracy of inhibin B, were assessed by the area under the receiver operating characteristic (ROC) curve.

RESULTS: In this study, 107 infertile patients were studied. Using the value of 283 pg/ml for inhibin B as the cut-off point, day 5 inhibin B had 77% sensitivity, 30% specificity, 31.2% positive predictive values (PPV) and 76.7% negative predictive values (NPV) for poor ovarian response. There were statistically significant correlation among day 5 inhibin B concentration and BMI, number of mature follicles, retrieved oocytes, developed and transferred embryos, chemical pregnancy, ovarian hyperstimulation syndrome (OHSS) and poor responder.

CONCLUSION: Although the chemical pregnancy, number of retrieved oocytes, developed and transferred embryos were higher in patients with higher day 5 inhibin B concentration but considering its sensitivity, specifity, PPV and NPV, it cannot be used as a strong test for prediction of cancellation, pregnancy, poor responses and OHSS.