Data from surveys on sexual behaviour conducted in twelve European cou
ntries are used to study the evolution in age at first intercourse ove
r the last fifty years. The age of women at sexual initiation fell mar
kedly during this period. whereas a smaller change was observed for me
n: and age at firn intercourse stabilized everywhere in the 1980s. The
AIDS epidemic developed in this context of relative stabilization and
although it has produced no change in the calendar of sexual initiati
on, the conditions of first intercourse have been modified, with use o
f the condom increasing at the expense of oral contraception. In this
ge neral context. two gender-based patterns of sexual behaviour can be
clearly identified. In the countries of southern Europe, the behaviou
r of women has become more like that of men, though women still have f
irst intercourse significantly later. In the Nordic countries, the age
s of men and women at sexual initiation have been similar for several
decades. There are numerous indicators, however. that in both northern
and southern Europe women experience sexual initiation very different
ly from men.