According to an article in the August 16th edition of the Los Angeles Times, sperm quality is down everywhere, but Israel is worse off than other developed countries.
Speculative theories range from the mundane (carrying cellphones in front pockets) to the far-fetched (depleted uranium from exploded munitions). Some Israeli scientists are looking seriously at naturally occurring hormones, particularly estrogen, in Israel's water and milk and suggest that it's a mark of the country's aggressive dairy farming methods and residual from birth control pills in womens' urine.
Over the last ten years I have made the same observations about the sperm of my patients' partners and it seem to be getting worse. Otherwise healthy men are showing up with significant motility (motion) and morphology (shape) issues. I believe it's caused by changes in the environment. I have seen pesticides on produce, hormones in meat and poultry, air pollution and electronic devices all postulated as possible causes. Who knows? Maybe it's global warming. After all heat is bad for the testicles. (Just kidding)
The real question is what can we do about it. Ultimately if the deficits are significant and we cannot achieve a pregnancy with conventional treatment, IVF with ICSI (direct injection of sperm into the egg) can usually overcome it. But to avoid the need for IVF I have been placing men with these changes on an intense vitamin and antioxidant regimen and have achieved some success. Of course they also have to make lifestyle changes such as stopping smoking, caffeine, recreational drugs and alcohol and sometimes that's the hardest thing to do.