Background: It is a common practice to repeatedly test the level of basal FSH early in the cycle and to start IVF treatment only when the FSH level is below a certain threshold value. This is based on the idea that these women will respond better to ovarian stimulation when the basal FSH level is lower at the start of the cycle. The aim of this study is to assess the value of this practice.
Methods: Between January 1995 and January 2003, 39 women were identified. These women underwent two IVF treatment cycles within a 12 month period. The basal FSH level prior to each of these cycles was known to have changed. The treatment cycles were divided into cycles with a high basal FSH (> or =10 IU/l) and cycles with a low basal FSH (<10 IU/l).
Results: The 39 women underwent a total of 78 treatment cycles (in the first cycle 20 had elevated level of FSH and 19 had low FSH and vice versa in the second cycle). Therefore, there were 39 cycles with high FSH and 39 cycles with low FSH. There was obviously no live birth in the first treatment cycle, hence the reason for the patient undergoing another treatment cycle within 12 months of the first one. In the high FSH group, six became pregnant [pregnancy rate (PR) = 15.4%] and five delivered [live birth rate (LBR) = 12.8%]. In the low FSH group, three became pregnant (PR = 7.7%) and two delivered (LBR = 5.1%). The difference in PR and LBR, however, was not significant. Neither were there significant differences between the two groups with regard to the number of oocytes collected, oocytes fertilized, embryos transferred or miscarriage rate.
Conclusion: The results of this study reveal that women who are poor responders or with reduced ovarian reserve have a poor outcome and repeatedly testing them will add no value. Cycling women with a history of elevated FSH should be offered treatment without further delay. Delaying treatment for these women could be counterproductive, as they may have to wait for many months, during which time they are getting older and closer to their menopause.