Background: Since women nowadays experience late decision for the delivery of the first child the question of screening strategies for ovarian reserve determination and fertility potential seems to be crucial. As the most reliable marker of ovarian function FSH determination has been used, but the method is limited with fluctuation from physiologic to pathologic levels up to some years before exhaustion of ovarian reserve. In the past ten years determination of anti-Müllerian hormone (AMH) concentration in serum has become most relevant. AMH is produced and secreted by granulosa cells and regulates the development of primary follicles with inhibitory action on FSH secretion. AMH does not only predict the pool of small antral follicles but can also be a predictor of oocyte quality. In men AMH determination has been useful in diagnostic procedures for intersex conditions with abnormal testicular differentiation, while in women AMH tends to be the most reliable marker for small antral follicle pool in premature ovarian failure and the marker of increased reserve of small antral follicles in women with polycystic ovaries. Conclusion: Recent scientific and clinical data suggest that AMH determination will be used as the most reliable marker of ovarian follicular status.