Maanvi Singh. Boy meets girl, sperm meets egg — how much does the age of each matter? Traditionally, research has focused on women's "biological clock. A study published Wednesday hints that age really might matter — in terms of the child's mental health. Researchers from Indiana University and the Karolinska Institute found that compared with children fathered by men who were years old, kids born to dads who were 45 or older were three times as likely to have autism and 13 times as likely to have ADHD.
The paternal age effect is the statistical relationship between paternal age at conception and biological effects on the child. The genetic quality of sperm, as well as its volume and motility, all may decrease with age,   leading the population geneticist James F. Crow to claim that the "greatest mutational health hazard to the human genome is fertile older males". The paternal age effect was first proposed implicitly by German physician Wilhelm Weinberg in  and explicitly by British psychiatrist Lionel Penrose in Evidence for a paternal age effect has been proposed for a number of conditions, diseases and other effects. In many of these, the statistical evidence of association is weak, and the association may be related by confounding factors or behavioural differences. Several studies have reported that advanced paternal age is associated with an increased risk of miscarriage.
Conception is the time when sperm travels up through the vagina, into the uterus, and fertilizes an egg found in the fallopian tube. Conception — and ultimately, pregnancy — can involve a surprisingly complicated series of steps. Everything must fall into place for a pregnancy to be carried to term. During ovulation, one of the ovaries releases an egg, which then travels down one of the fallopian tubes.
Alcohol, even in moderate amounts, can affect your sexual health. It can lead to loss of libido and infertility in both men and women. Learn more…. Learn about the different types of sperm motility and whether Y "boy" chromosomes actually swim faster than X "girl" chromosomes. Infertility is a problem for many men.