Obesity is not just related to diabetes alone but also with infertility.Overweight or obese men, like their female counterparts, have a lower chance of becoming a parent, according to a comparison of sperm quality presented at a European fertility meeting. In what they described as the biggest study of its kind, doctors looked at sperm samples from 1940 men and matched them to the donor's weight. The benchmark was the body mass index (BMI).

     "Excess weight causes a modification in sperm characteristics, probably as a result of hormonal disturbance, which results in lower sperm numbers, motility and vitality," said Paul Cohen-Bacrie, scientific director at Eylau-Unilabs in Paris, part of a Swiss-based network of labs in 12 European countries.The research found that the sperm count was lower by 10 per cent among overweight men, and by 20 per cent among obese men, compared with counterparts of normal weight