Obesity not linked to poor semen quality
NEW YORK (Reuters Health) - While overweight and obese men tend to have abnormal sex hormone levels, the quality of their semen doesn't seem to be affected, study findings indicate.
Dr. Anette S. Aggerholm and colleagues from Aarhus University Hospital in Denmark note in the medical journal Fertility and Sterility that the obesity epidemic has coincided with a decline in semen quality.
To investigate any connection, the researchers analyzed associations between body mass index (BMI) -- a measure of weight in relation to height -- and male sex hormones and sperm quality among some 2000 men.
The men, who were 18 to 66 years old and had no vasectomy or reproductive abnormalities, provided blood and semen samples, lifestyle information, and self-reports of body height and weight. Nearly half (47 percent) of the men were overweight.
Underweight men had the highest levels of sex hormones, the researchers found, and levels generally decreased as weight categories increased.
Aggerholm's team also noted that moderately overweight men showed a minor decrease in sperm density and total sperm count compared with men of normal weight. However, there was no drop in sperm count among the obese men.
These findings suggest a strong association between being overweight and hormonal changes, but not between obesity and semen quality, the investigators conclude.
SOURCE: Fertility and Sterility, September 2008
