Regular monitoring of ovarian response. Patients w/ porphyria or family history of porphyria. DM, hypothyroidism, adrenocortical deficiency, hyperprolactinemia & pituitary or hypothalmic tumours. Possible excessive oestrogen response & multiple follicular development. Ovarian hyperstimulation syndrome (OHSS). Multiple pregnancies, miscarriage or abortion, ectopic pregnancy on patients w/ history of tubal disease, benign & malignant ovarian & other reproductive system neoplasms. Recent or ongoing thromboembolic disease or recognized risk factor for thromboembolic events.