Historically, there has been a swing from the sexually liberal end of the Industrial Revolution to the chaste values of the early Victorian period. This was then followed by a new puritanism from the late Victorian era to the mid-1900s. This important transformation often colors discussion of sexual behavior in the later 20th century. World War I began a return to sexual freedom and indulgence, but more often than not, the appearance of conforming to the earlier moral values of abstinence before marriage was retained. With the conclusion of World War II, the societal importance of abstinence declined. The advent of the first oral contraceptive pill and widely available antibiotics suppressed many consequences of wide and free sexual behavior, while social morals were also changing. By the 1970s, abandonment of premarital chastity was no longer taboo in the majority of western societies, and the reverse became true. Some cultural groups continued to place a value on the moral purity of an abstainer, but abstinence was caught up in a wider reevaluation of moral values.