Human gonadotropin therapy: hormonal and ultrasonographic characteristics of conceptual and nonconceptual cycles in the same women.

A retrospective analysis was carried out to assess hormonal and sonographic characteristics of 52 conceptual (P-cycles) and 53 nonconceptual (F-cycles) gonadotropin treatment cycles in the same women. In the P-cycles, an exponential E2 pattern was observed up to the day of hCG (human chorionic gonadotropin) administration (day 0). In the F-cycle group, a similar pattern was observed till day (-1), and then levels plateaued. Forty-two (80.9%) of the pregnancies were achieved when the active phase was 6 +/- 1 days; seven pregnancies (14.8%) occurred when the active phase was more than 7 days. Only one of these pregnancies was a singleton viable pregnancy (P less than .05). It is, therefore, postulated that 6 +/- 1 days rising E2 and exponential E2 rise pattern up to the day of hCG are the two main monitoring variables leading to the highest percentage of viable singleton or twin pregnancies in hMG-stimulated cycles.