[Value of serum inhibin B measurement in predicting ovarian response in controlled ovarian hyperstimulation for in vitro fertilization cycle].

Objective: To explore the value of serum inhibin measurement in predicting ovarian response in infertile patients undergoing controlled ovarian hyperstimulation (COH) for in vitro fertilization (IVF) cycle.
Methods: A total of 37 patients undergoing their first cycles of IVF treatment were studied and serum estradiol (E(2)), progesterone (P), inhibin (INH) B, INHA levels were detected on days 2 - 4 and 21 of the previous cycle, on day 5 of gonadotropin therapy (day 5), hCG injection day, oocyte retrieval day and at middle luteal phase of the IVF cycle. According to number of oocytes, peak E(2) concentration and presence or absence of ovarian hyperstimulation syndrome (OHSS), the 37 patients were allocated into two groups: poor ovarian response group (group A), normal and high response group (group B). Characteristics of the treatment cycle and INH, E(2), P levels were analyzed. A multiple logistic regression model and receiver operating characteristic (ROC) analysis were then used for all possible prognostic variables to evaluate the value of different hormone in predicting ovarian response. The sensitivity and specificity were calculated at the discriminating cut-off point.
Results: (1) In group A, basal serum INHB level, INHB and INHA levels on day 5 of recombinant FSH (rFSH) stimulation were significantly lower than group B (P < 0.05), and basal serum INHB levels were (37 +/- 35), (91 +/- 90) ng/L respectively, INHB levels on day 5 of rFSH stimulation were (194 +/- 157), (2254 +/- 4765) ng/L respectively, INHA levels on day 5 of rFSH stimulation were (36 +/- 35), (91 +/- 90) ng/L respectively in groups A and B. (2) There was positive correlation between oocytes number and basal inhibin B and dynamic serum inhibin B levels, inhibin A and E(2) levels of rFSH therapy (INHB: r = 0.39 - 0.67, P < 0.05; INHA: r = 0.43 - 0.59, P < 0.01; E(2): r = 0.50 - 0.60, P < 0.01). (3) ROC analysis: day 5 inhibin B had the largest area under curve (AUC) 0.948 (95% CI: 0.871 - 1.025), indicating that a threshold of 400 ng/L gave 82.8% sensitivity, and 99.1% specificity.
Conclusions: The basal INHB levels and INHB measured on day 5 of rFSH stimulation may offer accurate and early prediction of ovarian response. Day 5 INHB levels are the best predictor of ovarian response.