BackgroundThe aim of this study was to evaluate the influence of three months of dietary intervention on menstrual cycle in young female athletes with amenorrhea or oligomenorrhea.MethodsFrom forty-five female professional athletes with menstrual irregularity that were recruited thirty-one, aged 18.1 ± 2.6 years, completed the study and were analyzed. Hyperprolactinemia, thyroid dysfunction, primary ovarian failure and hyperandrogenism were excluded in the study participants. The subjects started intense training at the age of 11.2 ± 3.5 years and continued during next 6.8 ± 3.3 years. Energy and nutrients intake, total energy expenditure, energy availability and body composition as well as serum concentrations of LH, FSH, 17 – beta estradiol and progesterone were measured at the beginning of the study and after three months of individualized dietary intervention.ResultsFollowing three months of dietary intervention significant increase in energy intake (2354 ± 539 vs. 258 8 ± 557 kcal, P = 0.004) and energy availability (28.3 ± 9.2 vs. 35.8 ± 12.3 kcal/kg FFM/d, P = 0.011) was observed as well as improved energy balance (−288 ± 477 vs. -51 ± 224 kcal/d, P = 0.002). Though no changes in BMI and body composition were noted but significant rise in LH concentrations (3.04 ± 1.63 vs. 4.59 ± 2.53 mIU/ml, P = 0.009) and LH to FSH ratio (0.84 ± 0.56 vs. 0.96 ± 0.52, P = 0.001) was achieved, but no restoration of menstrual cyclicity.ConclusionsThis report provides further support for the role of energy deficiency in menstrual disorders among young female athletes and the benefits of an adequate energy intake and energy availability on hormones concentration. Continuation controlled dietary intervention is needed to assess the extent to which long-term improvement in the nutritional status results in improvements in the hormonal status of female athletes, to an extent that would allow the regulation of the menstrual cyclity.