LH to FSH Ratio

LH to FSH ratio is the proportion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels measured in the blood. The normal ratio, when measured on day 3 of the menstrual cycle, is about 1:1. This ratio can be disturbed in women with polycystic ovarian syndrome (PCOS), with LH levels rising two to three times to that of the FSH.