Women's Health Research Institute

For those hoping to start a family, beer, cigarettes, and other drugs may not pose as threats to conception, but manual labor and tight undies are another story. Thanks to a recent study from the University of Manchester, a bit more light is shed on lifestyle factors and their affect on fertility in men.

Researchers Andrew C. Povey and colleagues decided to address the common belief that lifestyle factors–such as infrequent exercise and alcohol/drug use–can negatively impact semen quality, since much of the existing evidence on the topic is weak or inconsistent. Their study included UK men (age 18 and older) who had recently had unsuccessful attempts to conceive over 12 consecutive months of unprotected intercourse (the standard clinical definition for infertility). Participants completed a questionnaire relating to lifestyle factors, job responsibilities, and health issues, underwent an in-person interview to elaborate on these responses, and then gave a semen sample. This sample was analyzed for motility (biological term for movement and energy expenditure), concentration, and quality.

Being non-white, older, and having previous testicular surgery were associated with decreased fertility, as were behaviors including manual labor and wearing of jockey shorts (versus boxers). Researchers posit that certain forms of manual labor might expose workers to toxins that are not a threat to non-manual laborers, but believe that there are other differences between these types of labor that could also contribute to reduced sperm quality. Surprisingly, having a high BMI (body mass index), smoking, drinking, and drug use were not associated with any significant decrease in fertility. The validity of popular advice for sperm quality improvement remains questionable, but Covey said that the study points to specific modifiable behaviors–wearing loose underwear, avoiding certain types of manual labor–as potentially helping to improve sperm quality and overall fertility in men.

You can read the full study here.

Via Well Blog, NYTimes.