Resumption of fertility with diet in overweight women.

In young women being overweight appears to be one of the major and still neglected causes of subfertility. Not only the excessive amount but also the distribution of body fat is clearly related to loss of fertility. The mechanism through which obesity impairs ovulation and fertility is largely unknown, but it is well known that being overweight lowers the concentration of sex hormone binding globulin and increases androgen and insulin secretion and insulin resistance. These high concentrations of androgen and insulin in turn are important factors in the preferential abnormal localization of body fat. In addition, ovulation induction or ovarian stimulation in overweight women is a not easy task, since these patients are often unresponsive to the stimulatory drugs and, in addition, have a higher rate of miscarriages. Weight reduction improves these patients' biochemical indices and fertility rates. The spontaneous pregnancy rate can be expected to be around 30%, but an additional 40-50% drug-induced pregnancy rate can be achieved with a 10-15% weight loss. Drugs increasing insulin sensitivity also improve spontaneous ovulation and fertility in obese women but still need to be tested in larger controlled trials. In conclusion, appropriate counselling about weight reduction through diets and exercise can restore both health and fertility, avoiding much frustration, and saving time and money.