Müllerian-inhibiting substance reflects ovarian findings in women with polycystic ovary syndrome better than does inhibin B.

OBJECTIVE

To investigate Müllerian-inhibiting substance (MIS) levels in women with polycystic ovary syndrome (PCOS), as well as relationships to ovarian morphology, levels of inhibin B, and other reproductive hormones.

DESIGN

Prospective clinical study.

SETTING

Academic endocrinology centers in Palermo, Italy and New York.

PATIENT(S): Forty-six women with PCOS, recruited on the basis of the classic criteria of chronic anovulation and hyperandrogenism, and 25 age-matched ovulatory controls.

INTERVENTION(S): Fasting blood was obtained in all subjects in the early follicular phase (days 5-6) after spontaneous or induced menses (in PCOS), and transvaginal ultrasounds were performed.

MAIN OUTCOME MEASURE(S): Assessment of values for luteinizing hormone (LH), testosterone (T), androstenedione (A), estradiol (E2), inhibin B, MIS, fasting insulin, and the calculated quantitative sensitivity check index (QUICKI), as well as assessments of ovarian volume and blood flow.

RESULT(S): Women with PCOS had higher LH, T, and A; higher insulin and lower QUICKI; and higher ovarian volume and lower pulsatility index. Inhibin B concentrations were statistically significantly higher in PCOS patients (70 +/- 8.0 vs. 40 +/- 3.4 pg/mL), as was MIS (6.7 +/- 0.9 vs. 4.6 +/- 0.5 ng/mL). Inhibin B had a statistically significant direct correlation with levels of MIS (r = 0.351). However, MIS, but not inhibin B, had a statistically significant positive correlation with ovarian size (r = 0.350); the reproductive hormones LH, T, A, and E2; and insulin (r = 0.249), independent of body mass index. Women with PCOS with the highest levels of MIS had higher ovarian volumes and values of LH, T, A, and insulin.

CONCLUSION(S): Measurements of MIS reflect ovarian findings in PCOS better than levels of inhibin B and are more frequently elevated. However, MIS lacks sensitivity for use as a diagnostic tool in PCOS.