While it is true that high birth rates in Third World countries is a population concern, its opposite – low fertility – is becoming a trend in developed countries in North America and Europe.
Yes, our Earth is already heavily populated – by that we mean that there are more people than resources to feed and nurture them. So, what is the concern about low fertility?
Well, there are economic, sociological, and political reasons. For one, low fertility produces an age structure that cuts down the young population and enlarges the old sector, making society very unsustainable. We will not expound that area as it has been discussed thoroughly in other venues; we would like to focus on low fertility as a personal health problem.
Take the case of male fertility. It was in 1991 when a Danish study found that sperm counts of Western men had fallen by about half in 50 years. Until now, no one has explained it. Unlike women whose eggs are finite, men produce sperm constantly. So, what are some of the factors considered:
Dietary Factors: This includes such factors as FAST FOOD (found to contain chemicals that mimic estrogen); INORGANICALLY PRODUCED FOOD (For example, a study involving 225 Argentinian men found a direct link between those pesticide exposure and low sperm county).
DRIVING (there is a vast study that shows that sitting behind the wheel for long periods is bad for sperm); LAPTOPS (with the laptop sitting on your, well, lap, the radiation exposure lowers sperm production according to a study published in the journal Human Reproduction); and of course MOBILE PHONES (according to a study from the University of Szeged in Hungary, mobile phones could lower sperm counts by up to a third because of the radiation they emit.)
Environmental Factors: TRAFFIC POLLUTION (Studies have shown that the nitrogen oxide and lead in exhaust fumes adversely affect sperm quality).
But, perhaps the most prevalent factor especially in Canada and the US, are the factors involving personal lifestyle. This includes:
In a recent systematic U.K. review of 21 studies following women who smoked, “95 percent of women were found to have significantly lower odds of getting pregnant naturally or carrying a baby to term, as well as significantly higher odds of miscarriage and ectopic pregnancy. Men who smoke have significantly lower sperm count than those who don’t.”
There are several studies to show that drug abuse affects fertility. Marijuana for example has been shown to lower the number of sperm in men, decreasing fertility. “With use of other drugs, such as cocaine and methamphetamines, miscarriage rates increase, as does the risk of placental abruption, a condition where the placenta separates from the wall of the uterus.”
Fertility experts have shown that obesity is directly shown to male and female fertility. A lot of that is because of the heat produced by the fats near the groin area.
Among other things, alcohol disrupt the absorption of nutrients, create more work for your body (and liver!), and weaken your immune system. But alcohol also raises prolactin levels which can interfere with ovulation, disrupt women’s menstrual cycle and can lead to abnormalities in the endometrium. For men, alcohol affects erection and sperm count.