Such covertly illegitimate children amount to about 1–2% of newborns in studied populations.
According to The New York Times, the most consistent data on infidelity comes from the University of Chicago's General Social Survey (GSS).
A survey conducted in 1990 found 2.2% of married participants reported having more than one partner during the past year.
In general, national surveys conducted in the early 1990s reported that between 15–25% of married Americans reported having extramarital affairs.
Studies suggest around 30–40% of unmarried relationships and 18–20% of marriages see at least one incident of sexual infidelity.When they are not met, research has found that psychological damage can occur, including feelings of rage and betrayal, lowering of sexual and personal confidence, and damage to self-image.Depending on the context, men and women can experience social consequences if their act of infidelity becomes public.Another study found that the likelihood for women to be involved in infidelity reached a peak in the seventh year of their marriage and then declined afterwards; whereas for married men, the longer they were in relationships, the less likely they were to engage in infidelity, except for the eighteenth year of marriage, at which point the chance that men will engage in infidelity increases.
One measure of infidelity is covert illegitimacy, a situation which arises when someone who is presumed to be a child's father (or mother) is in fact not the biological parent.Other scholars define infidelity as a violation according to the subjective feeling that one's partner has violated a set of rules or relationship norms; this violation results in feelings of sexual jealousy and rivalry.In marital relationships, exclusivity expectations are commonly assumed, although they are not always met.They are attracted to western men because these men are deemed to be romantic, caring, family oriented, responsible and chivalrous.