The serum follicle-stimulating hormone-to-luteinizing hormone ratio at the start of stimulation with gonadotropins after pituitary down-regulation is inversely correlated with a mature oocyte yield and can predict "low responders".

OBJECTIVE: The aim of this study was to investigate the relationship of serum FSH and LH levels at the commencement of stimulation to ovarian follicular development in women undergoing pituitary down-regulation and controlled ovarian hyperstimulation with gonadotropins in IVF or intracytoplasmic sperm injection (ICSI) cycles.

DESIGN: Retrospective analysis.

SETTING: An IVF program in a tertiary medical center.

PATIENT(S): A total of 245 women proven to be pituitary down-regulated by their serum E(2) levels.

INTERVENTION(S): Patients treated with a GnRH agonist and FSH and hMG underwent assisted reproductive technique (ART).

MAIN OUTCOME MEASURE(S): Mature oocyte yield, pregnancy rate (PR), and live birth rate.

RESULT(S): The serum FSH levels and the FSH-to-LH ratio at the commencement of gonadotropin stimulation were inversely correlated to the number of mature oocytes (r = -0.193 and r = -0.224, respectively). When assessed with receiver-operating characteristic (ROC) analysis, there was statistically significant ability for the FSH/LH ratio to differentiate between the "poor response" cycles (with mature oocyte yield < or =4) and the normal response cycles. Using the cutoff value derived from ROC analysis, cycles with the FSH-to-LH ratio > or =3 produced less mature oocytes (8.25 vs. 11.74), lower peak E(2) levels (1,975.3 pg/mL vs. 3,324.8 pg/mL), and higher percentage of poor ovarian response cycles (32.5% vs. 14.3%).

CONCLUSION(S): The serum FSH-to-LH ratio at the start of gonadotropin stimulation after pituitary down-regulation provided a practical method for early prediction of mature oocyte yield.