Patterns of serum-luteinizing hormone surges in stimulated cycles in relation to injections of human chorionic gonadotropin.

Endogenous-luteinizing hormone (LH) surges may complicate the management of in vitro fertilization cycles. To investigate the effects of LH surges after hormonal stimulation 53 IVF cycles were analyzed by assessing LH levels three times daily until egg collection. In 43% the LH rise started before the planned exogenous trigger for ovulation was given, in 11% the rise occurred simultaneously with and in 45% after the injection of human chorionic gonadotropin. Three main patterns of serum LH surges were identified: (A) low-LH tonus with straight increase to maximum; (B) low tonus with elevation before straight increase; (C) high tonus with large variations but no prominant peak. These patterns were not related to the follicular estradiol increase, luteal steroid concentrations or resulting pregnancy rates.