Ovulation induction with human menopausal gonadotrophins: an evaluation of a variable daily dosage regimen.

Human menopausal gonadotrophins (HMG) were used together with human chorionic gonadotrophin (HCG) in 19 women and 39 treatment cycles in an attempt to induce ovulation. Daily 24 hours urinary total estrogen excretion rates were measured and HMG daily dosage was varied according to levels obtained. HCG injections were timed to coincide with an estimated urinary total estrogen excretion rate of 100-150 g per 24 hours. Thirty-one ovulatory cycles occurred (79%) and there were nine pregnancies (23%) of which five were multiple. Eleven cycles were complicated by hyperstimulation (25.6%) of which six were severe. The variable HMG dosage regimen was found to offer no advantages when compared with our standard daily dosage regimen. A rapid rise of estrogen excretion occurred in over 80% of hyperstimulation cycles, including all severe ones, and it was found that this rise could occur after the last dosage of HMG had been given. Because of this, it is proposed that HCG injections be delayed until 48 hours after the last injection of HMG. The finding of a value for the last available 24 hour urinary total estrogen excretion of less than 150 microgram can be taken as an indicator that hyperstimulation is unlikely to occur, and that HCG can safely be given. No indication was found that such a procedure would diminish ovulation or pregnancy rates.