[Diagnosis, incidence and clinical significance of premature LH rise/peak in patients of an in vitro fertilization and gamete transfer program].

In this study we analysed the prevalence and the clinical relevance of premature (related to the day of ovulation induction with HCG) LH rise (LH greater than or equal to 180%, but less than 300% of the mean of all previous values) or peak (LH greater than or equal to 300% of the mean of all previous values): 12% (2/16) of the conception cycles showed a premature LH peak, 44% (7/16) a premature LH rise and 44% (7/17) showed neither a premature LH rise nor a premature LH peak. The pregnancy rate of cycles with premature LH peak was found to be 10% (2/21), without premature LH peak 37% (7/19). These results indicate, that the premature LH peak represents an unfavourable condition for achievement of pregnancy; the cancellation of such stimulations before oocyte retrieval is recommended. On the other hand, cycles with premature LH rise need not be cancelled. The fertilisation rate was independent of an LH rise/peak (no LH rise/peak: 55%, LH rise: 62%, LH peak: 46%): it is supposed, that the premature LH peak causes submicroscopical injury of the oocyte and although fertilisation is possible, further embryonic development will be hindered. The use of the GnRH analogue Buserelin in combination with HMG leads to a significantly (p less than 0.001) lower prevalence of the premature LH peak (16%; 7/44 versus 51%; 48/95); the combined Buserelin + HMG stimulation is recommended for treatment of premature LH peak.