Clinical manifestation of anovulation is oligomenorrhea or amenorrhea. Patients with hyperandrogenemia and polycystic ovaries (without ovulation disorders) and patients with polycystic ovaries and ovulation disorders (without hyperandrogenism) may now be included in polycystic ovary syndrome (PCOS) diagnosis. The majority of anovulatory patients (about 80%) will have normal serum concentrations of estradiol (E2) and follicle-stimulating hormone (FSH) and a small proportion (approximately 10%) decreased concentrations of both hormones. Traditionally, ovulation induction treatment in normogonadotropic anovulation is started with an antiestrogen (CC) and, in case of treatment failure or absence of conception, this is followed by exogenous FSH. The most serious complications resulting from ovulation induction are caused by the limited control of follicular development. Increased availability of genetic profiles will be helpful to accomplish a more patient-tailored approach by identification of beneficial subgroups for certain interventions.