"Male reproductive health is in trouble," say two new studies, so urgent guidelines are needed for men of breeding age, just like for pre-pregnant wimmins. In case you'd forgotten:
New federal guidelines ask all females capable of conceiving a baby to treat themselves -- and to be treated by the health care system -- as pre-pregnant, regardless of whether they plan to get pregnant anytime soon.
Among other things, this means all women between first menstrual period and menopause should take folic acid supplements, refrain from smoking, maintain a healthy weight and keep chronic conditions such as asthma and diabetes under control.
Potential causes for the problems with male reproductive health include carcinogens (like from cigarettes), chemicals (like dioxins), hormones (like from American beef, or milk), and endocrine disruptors (such as found in many plastics). So all men capable of inseminating have a pretty long list of substances to avoid: smoking, beef, dairy products, most personal care products, bottled water, etc.
Details from Grist: Separate studies show chemicals, cigarettes may affect male birth rate :
The percentage of boys born in the U.S. and Japan each year has gradually declined over the last three decades, a new study says -- and pollutants are a possible cause. "Male reproductive health is in trouble," says lead researcher Devra Lee Davis of the University of Pittsburgh, noting that both adult fertility and fetal chances seem to be affected. The study, published in the online journal Environmental Health Perspectives, calls the trend "a serious matter" that could be caused by exposure to chemicals like dioxin and mercury; it also points to factors including stress, obesity, and fertility treatments. The true cause, says Davis, is "something we need to find out and act upon." Because a woman without a man -- well, she'd probably be fine, but still. Meanwhile, a British study says smokers are twice as likely to conceive girls, suggesting that nicotine may affect sperm. Yes, smoke gets in your Y's -- but picking up puffing in an effort to determine your child's gender is not recommended.
More info here and here