Achieving a distinct ovarian response usually represents the desired outcome of pharmacological interventions on the hypothalamic-pituitary-ovarian axis in ovulation induction and ovarian stimulation. The considerable individual variability in ovarian response to stimulation, however, necessitates close monitoring and dose adjustment for each woman. Combining prediction models for success in ovulation induction and success in conception would allow prediction of the likelihood of conception before anti-estrogen therapy is initiated, allowing women with a low percentage chance of a live birth to be directed towards another first-line treatment modality. Gonadotrophins are commonly used as a second-line treatment to restore ovarian function in women with WHO group II anovulation who have not responded to anti-estrogen therapy. Despite problems in using the current predictive tests in clinical practice, the wide variation in patients' characteristics mean that individualised patient-tailored approaches remain mandatory for safe and effective ovarian stimulation.