The impact of LH serum concentration on the clinical outcome of IVF cycles in patients receiving two regimens of clomiphene citrate/gonadotrophin/0.25 mg cetrorelix.

Clomiphene citrate treatment with the association of gonadotrophins and the GnRH antagonist cetrorelix 0.25mg was analysed in two different stimulation protocols for IVF. In protocol I, 18 patients were sequentially stimulated with clomiphene citrate and gonadotrophins. In protocol II, 28 patients started the gonadotrophin injections during the clomiphene citrate administration. LH values significantly dropped after the first 0.25 mg cetrorelix injection in both protocols. A total of 22% and 7% of cycles were cancelled in protocols I and II, respectively, because of poor follicular development. The clinical pregnancy rate following embryo transfer was 18.1% in protocol I and 29.1% in protocol II. In two (11.1%) cycles stimulated according to protocol I and in eight (28.5%) cycles from protocol II, premature LH surges occurred. In patients with premature LH surge, significantly fewer metaphase II oocytes were obtained. The clinical pregnancy rate following embryo transfer was 12.5% in patients with surge compared with 29.6% in patients without. LH values were lower before HCG injection in patients who achieved pregnancy in the study cycle. In conclusion, sequential clomiphene citrate and gonadotrophin administration is not recommended for clomiphene citrate/gonadotrophin/cetrorelix 0.25 cycles. Cetrorelix 0.25 mg/day was associated with a high incidence of premature LH surges and premature LH surges were associated with an adverse cycle outcome.