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Updated: Jun 23, 2026

A Hyperandrogenic Mouse Model to Study Polycystic Ovary Syndrome
Published on: October 2, 2018
Hyperandrogenism may explain reproductive dysfunction in olympic athletes
Magnus Hagmar1, Bo Berglund, Kerstin Brismar
1Department of Woman and Child Health, Division of Obstetrics and Gynecology, Karolinska Institutet, Stockholm, Sweden. magnus.hagmar@karolinska.se
Purpose:
Female athletes are known to be at risk for reproductive dysfunction and osteopenia because of energy deficiency. Although endocrine balance and an optimal body composition are essential for top elite performance, these parameters have not yet been explored fully in Olympic sportswomen. The objective of this study, therefore, was to characterize the menstrual status, body composition, and endocrine balance in female Olympic athletes participating in different disciplines.
Methods:
Ninety Swedish female Olympic athletes underwent a gynecologic examination that included vaginal examination by ultrasound and determination of body composition. In addition, blood samples were collected for the analysis of reproductive hormones and biomarkers of energy availability.
Results:
Of all the athletes, 47% were using hormonal contraception (HC). Menstrual dysfunction (MD) was common (27%) among those not using HC and, particularly, in endurance athletes. However, the proportion of body fat and biomarkers of energy availability were within the normal ranges and none exhibited osteopenia. On the contrary, bone mineral density was generally high, particularly in the power athletes. The most common diagnosis associated with MD was polycystic ovary syndrome (PCOS) and not hypothalamic inhibition because of energy deficiency.
Conclusions:
Female Olympic athletes participating in different sports were found to have an anabolic body composition and biomarkers of energy availability within the normal ranges. Most cases of menstrual disturbances observed were due to PCOS. These findings challenge the contemporary concept that reproductive dysfunction in sportswomen is typically a consequence of chronic energy deficiency.
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