Reduce your chemical exposure.

"The semen of the average man today has half the sperm, and of poorer quality, than 50 years ago. This is believed to be caused by exposure to xenoestrogens (PCBs, DDT, dioxin, other pesticides, plastics and industrial pollutants) that mimic the effects of estrogen. You can prevent or minimize the impact of xenoestrogens on your health by doing the following: + Avoid plastic containers for food storage, plastic bottles, wraps and utensils. + Use office paper products whitened without chlorine. + Use only non-bleached coffee filters, paper, napkins and toilet tissue to reduce dioxin exposure. + Avoid chlorinated tap water, chlorine bleach and other chlorinated products; use hydrogen peroxide as an alternative. + Eat organic food as much as possible to avoid pesticides and herbicides."

Source: Alive Health