A review of luteinizing hormone and its role in ovarian reserve testing

Background: Ovarian physiology illustrates the synergistic interaction between luteinizing hormone and follicle stimulating hormone in the process of folliculogenesis. While follicle stimulating hormone has been well established as a marker of ovarian reserve, the role of luteinizing hormone has remained somewhat controversial and it seems to have become the ‘forgotten gonadotropin’. The following review aims to investigate the available evidence surrounding luteinizing hormone as an ovarian reserve test and examine the issues which need to be addressed in order to establish it as an ovarian reserve test. It then further attempts to propose a model to direct effective research to ascertain if it does have a role to play in ovarian reserve testing. Findings: The evidence is equivocal in the use of luteinizing hormone as an independent predictor of ovarian reserve. However, there is much stronger evidence to suggest that the follicle stimulating hormone/luteinizing hormone ratio is a useful marker of ovarian reservein particular when it is ≥2 and approaching 3. The evidence base for this ratio at present however is sparse. In addition, ovarian reserve tests are fraught with issues over reliability, accuracy, definition and the implications of testing itself. In order to overcome these issues, more quality research needs to be carried out to test this relationship between luteinizing hormone and follicle stimulating hormone.