Popis: |
Adipose tissue is essential for the normal development of female reproductive function, however, obesity causes menstrual disturbances and subfertility. The severity of obesity and the distribution of fat tissue are important factors that influence the female reproductive system. Obesity results from combined genetic and environmental factors and is one of the most frequent diseases and is encountered all over the world. A body mass index (BMI) that is either high or low is associated with reduced probability of achieving pregnancy in women. Body mass affects reproduction by causing menstrual disturbance and anovulation. During the last decades the pathophysiological and molecular mechanisms of this relationship were gradually elucidated. The obesity influences the reproductive cycle by impaired estrogen metabolism, changes in the concentration of sex hormone binding (SHBG) globulin, hyperinsulinaemia, and probably also leptin levels. The role of leptin still remains unclear in human reproduction, though there is growing evidence that it seems to play an important role. This increased BMI is also associated with the risk of several diseases, such as diabetes mellitus, osteoarthritis, cardiovascular diseases, sleep apnoea syndrome, breast cancer, cancer of the uterus and besides impairment of reproductive functions. |