Diagnosis-specific serum 17 beta-estradiol (E2) upper limits for treatment with menotropins using a 125I direct E2 assay

Statistical evaluation of 133 cycles of induction of ovulation using generalized linear models demonstrated that the occurrence and severity of ovarian hyperstimulation was influenced by the serum 17 beta-estradiol (E2) concentration (P less than 0.001), conception (P less than 0.001), and the endocrinologic diagnosis, polycystic ovary syndrome (PCO) or hypothalamic amenorrhea (HA) (P less than 0.01). When menotropins were administered between 5:00 P.M. and 8:00 P.M. and blood was drawn at 8:00 A.M., an upper limit for serum E2 in patients with HA of 2417 pg/ml or an upper limit for patients with PCO of 3778 pg/ml gave an approximate 5% risk of severe ovarian hyperstimulation in conception cycles and a 1.3% risk of severe hyperstimulation in nonconception cycles. Comparison of our E2 radioimmunoassay involving extraction and chromatography to the Pantex immunodirect Estradiol 125I kit (Pantex, Santa Monica, CA) demonstrated no detectable systematic error, allowing the use of these limits with either assay. The ovulating injection of human chorionic gonadotropin was given at 5:00 P.M. to 8:00 P.M. on the evening of blood drawing as soon as the first follicle reached an average diameter of 14 mm or greater. The ultrasound parameters allow the chance of pregnancy to be optimized and the chance of multiple gestation to be minimized. Serum E2 monitoring indicates when the risk of ovarian hyperstimulation is too great for human chorionic gonadotropin to be given.