Assessment of follicular development by ultrasonography and total serum estrogen in human menopausal gonadotropin-stimulated cycles.

Ovarian follicular development was assessed by serial ultrasonography in infertile women being treated with human menopausal gonadotropin. Both follicular size and number of follicles correlated with serum estrogen values in most patients, and follicles increased in size 2--3 mm per day. Most patients had serum estrogen values greater than 750 pg/ml when one or more follicles larger than 18 mm were present. A comparison of conception cycles with non-conception cycles did not reveal a significant difference in size or number of follicles, or in the rate of rise or peak value of serum estrogen. When women monitored with ultrasonography were compared with patients treated with gonadotropins prior to the availability of ultrasonography, there was no significant difference in the rates of successful conception, although the number of ampules of pergonal used by the former was significantly reduced, permitting more efficient use of an expensive medication.