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Updated: Jun 20, 2026

Evaluation of Hepatic Glucose Production in a Polycystic Ovary Syndrome Mouse Model
Published on: March 5, 2022
The LH/FSH ratio has little use in diagnosing polycystic ovarian syndrome
Li Wei Cho1, Vijay Jayagopal, Eric S Kilpatrick
1Department of Medicine, University of Hull, Hull, UK. L.Cho@hull.ac.uk
Background:
The luteinizing hormone/follicle stimulating hormone (LH/FSH) ratio is often requested to help diagnose polycystic ovarian syndrome (PCOS) despite a recent consensus recommending against its use. This study aimed to compare the variability of the LH/FSH ratio in PCOS with that of normal menstruating women over a full cycle in order to establish the diagnostic utility, or otherwise, of the test.
Methods:
Twelve women with PCOS and 11 matched controls had blood collected at four-day intervals on 10 consecutive occasions over a complete menstrual cycle.
Results:
The median LH/FSH ratio for individual subjects did not differ significantly between the PCOS and the non-affected group (1.6 versus 1.2, P = 0.14). Only 7.6% of samples from PCOS patients had an LH/FSH ratio above three, compared with 15.6% of samples from normal subjects.
Conclusion:
This study confirms that measurement of the LH/FSH ratio is of limited use in the diagnosis of PCOS.
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