Oral contraceptive therapy reduces serum relaxin-2 in elite female athletes

Non-randomised trial OA: closed CC0
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Oral contraceptive therapy significantly reduced serum relaxin-2 levels in elite female athletes, particularly in those with high levels during the luteal phase.

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Abstract

AIM: Recent investigations have demonstrated that athletes with high relaxin-2 levels have a high risk of anterior cruciate ligament injuries, while athletes taking oral contraceptives (OC) have low relaxin-2 levels. It has not yet been clarified whether taking OC reduces relaxin-2 levels. The purpose of this study was to investigate changes in relaxin-2 levels in athletes taking OC. METHODS: Levels of relaxin-2, estradiol, progesterone, luteinizing hormone and follicle-stimulating hormone were measured in serum samples (n = 183) from 106 elite female athletes. Five athletes with serum relaxin-2 concentrations > 6 pg/mL during the luteal phase were recruited to assess the effect of OC therapy. RESULTS: Serum relaxin-2 concentrations were significantly higher during the luteal phase (n = 57) than in the follicular phase (n = 72), or in athletes on OC therapy (n = 10) (P < 0.001, P < 0.001 and P 6 pg/mL. In 23 athletes, serum relaxin-2 concentrations were measured during both the follicular and luteal phases, revealing that relaxin-2 levels were significantly higher in the luteal phase compared with the follicular phase. In 5 out of 23 athletes, serum relaxin-2 concentrations were > 6 pg/mL in the luteal phase and during the second cycle of OC therapy, relaxin-2 concentrations decreased dramatically to below the detection limit (0.26 pg/mL). CONCLUSIONS: High serum relaxin-2 concentrations were only detected during the luteal phase. In athletes with high relaxin-2 concentrations during the luteal phase, OC therapy decreased serum relaxin-2 levels.

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MeSH descriptors

Athletes Contraceptives, Oral Relaxin Adult Amenorrhea Amenorrhea Contraceptives, Oral Estradiol Estradiol Female Follicle Stimulating Hormone Follicle Stimulating Hormone Humans Luteinizing Hormone Luteinizing Hormone Menstrual Cycle Menstrual Cycle Progesterone Progesterone Relaxin

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openalex
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pubmed
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License: CC0 · commercial use OK