estrogen provocation test estrogen provocation test the estrogen provocation test, also known as the estrogen stimulation test or estrogen challenge test, is a diagnostic procedure used to evaluate the function of the hypothalamic–pituitary–gonadal axis. it involves the administration of a large amount of estrogen, resulting in estrogenic exposure similar to or greater than normal preovulatory estradiol levels, in an attempt to induce a positive feedback surge in levels of the gonadotropins, luteinizing hormone (lh) and follicle-stimulating hormone (fsh). estrogens that have been used in the estrogen provocation test include estradiol benzoate, estradiol valerate, ethinylestradiol, and high-dose transdermal estradiol patches. the test involves sustained estrogenic exposure equivalent to estradiol levels of 200 to 300 pg/ml or more for at least 50 hours and results in a surge in gonadotropin levels about 32 to 72 hours following initiation of estrogenic exposure. levels of lh and fsh increase during the gonadotropin surge by about 10-fold and 4-fold, respectively. estrogen provocation testsynonymsestrogen stimulation test; estrogen challenge testpurposeevaluate hypothalamic–pituitary–gonadal function an estrogen provocation test showing gonadotropin surge after a single intramuscular injection of estradiol benzoate early in the menstrual cycle in normal premenopausal women.