The purpose of this study was to assess factors associated with the us
e of family planning at first sexual intercourse among young adults ag
ed 15 to 24 in urban Ecuador. The study population consisted of 1443 y
oung adults (494 females and 949 males) in the cities of Quite and Gua
yaquil, interviewed by the 1988 Ecuador Young Adult Reproductive Healt
h Survey, who reported having experienced consensual sexual intercours
e. Approximately 11% of females and 15% of males reported using contra
ception at first intercourse. Binary logistic regression was performed
to assess jointly the effect of multiple factors on contraceptive use
at first intercourse. The regression model was first run on the entir
e study population and then separately for males and females. In the o
verall population, the following variables were significantly related
to using family planning at first sex: being male; being from Guayaqui
l; older age; father's completion of secondary school. Having lost one
's virginity to a prostitute was significantly associated with non-use
of family planning. Males were 3.6 times more likely than females to
use family planning during their first sexual intercourse. For each ye
ar older a young adult was at first sex, his or her odds of using fami
ly planning was multiplied by a factor of 1.3. Twenty-eight per cent o
f males in this study experienced their first sexual intercourse with
a prostitute, and these young men were highly unlikely to use family p
lanning. A male who experienced first intercourse with his girlfriend
was more than five times as likely to use contraception than a male wh
o lost his virginity to a prostitute.