Depending on what you read and where British sperm counts are up to30% lower now than in the '50s and according to some they are dropping( sperm counts) at a rate of 3%/annum.
It is linked to Tofu and soya products( soya has a chemical in it which mimics female hormones),saturated fats, oestrogen in the water, plastics by products that mimic female hormones, tight trousers, excessive bishop bashing and reading the Reg.
In spite of all that there is still a housing shortage, it's impossible to get a seat on a bus or train or easily park a car.
As far as the pollutants are concerned, they are worse and more prevalent in those countries that are emerging markets like India, China etc. They seem to have no problems expanding their populations so perhaps the guys who go to sit in a cubicle for science are the ones at fault.
Personally, three of the five women I really fancy are pregnant, and I've only leered at them!
So who needs sperm?