"marital intercourse" is a grammatically correct and usable term in written English.
You can use it to refer to sexual activity between married partners. For example: "Many couples cite having regular marital intercourse as an important part of a successful marriage."
The reduction in the frequency of marital intercourse or even its abandonment is more often than not the result of male deterioration.
In males the frequency of marital intercourse falls from an average of four per week in 20-year-olds to one per week in 60-year-olds.
"[A]bstinence from all sexual union is better even than marital intercourse performed for the sake of procreating," and the unmarried state is best of all (The Excellence of Marriage, ca. 401, §6, 13/15).
He defends the family as a social institution against the criticisms of Plato (Politics II.3 4), and so when he says that adultery is always wrong, he is prepared to argue for his point by explaining why marriage is a valuable custom and why extra-marital intercourse undermines the relationship between husband and wife.
… [However], pre-marital intercourse [is] strictly unacceptable for 'respectable' women [and] considered to be highly damaging to the reputation of [her] and her family'.
In Antichrist he does it again, this time in slow-motion close-up, during the poetic bout of marital sexual intercourse that begins the film.
Marital coitus is not unrestricted.
The prevalence of pre-marital sexual intercourse among adolescents ranges from below 5% to over 50% depending on national differences in traditional culture and socioeconomic environment [ 30- 32].
Although the prevalence of pre-marital sexual intercourse was lower in our study than in many other countries [ 31, 32], the prevalence of risky sexual behaviors was higher.
Young people in this region frequently engage in pre-marital sexual intercourse, with consequences such as unplanned pregnancy [ 3], sexually transmitted infections (STIs) [ 4], and HIV/acquired immunodeficiency syndrome (AIDS) [ 5, 6].
The prevalence of pre-marital sexual intercourse among senior high school students in China is low when compared with other countries, but that of the risky sexual behaviors is high.
