STI - Epi Update
April 1998
Oral Contraceptive and Condom
Use
Reported cases and incidence rates of some sexually transmitted
diseases (STDs) in Canada have been falling. Despite that, rates of
STDs continue to be well above average among Canadians aged 15-24,
especially for chlamydia and gonorrhea1. Therefore, it
is especially important that Canadian youths protect themselves
against STDs. Although delay of onset of sexual intercourse or
abstinence are effective ways for youth to avoid STDs, the
appropriate use of condoms is an effective way to reduce STD
transmission among those who choose to be sexually active.
Unrecognized or untreated infections can lead to severe
complications among women, such as pelvic inflamatory disease
(PID), ectopic pregnancy and infertility. Intact latex condoms
provide a continuous mechanical barrier against bacteria such as
chlamydia and gonorrhea and viruses such as HIV, genital herpes
virus and hepatitis B virus.
There is some concern that Canadian adolescents may be putting
themselves at unnecessary risk of STD by choosing the oral
contraceptive pill (OCP) for prevention of pregnancy while
remaining at risk of acquiring an STD through unprotected sex. The
problem appears to be with the interplay between the need to
prevent pregnancy and the need to protect against STD. There is no
single method that is completely effective in protecting against
pregnancy and STD. The contraceptives that are most effective in
preventing pregnancy, such as the oral contraceptive pill or an
intrauterine device, offer no protection against STD. Condoms, on
the other hand, offer protection against STD but are not the most
effective contraceptive. This STD Epi Update outlines some of the
relationships between use of oral contraceptives and condom
use.
Use of the OCP must be accompanied by concomitant use of
a condom
- Females who use the OCP to prevent pregnancy should also use a
condom to protect against STD; however, research data indicate that
females who use OCP do not necessarily consider using a condom for
STD prevention2.
- In a large Canadian study (n=1438) completed in 1995, only 27%
of current OCP users reported concurrent use of
condoms3.
STD risk is often underestimated by those who choose
OCP
- A secondary analysis of the college/university subset of the
Canada Youth and AIDS Study (mean age 19.7 years) found a complex
relationship between the number of partners, condom use, and the
use of OCP. Students with more sex partners were more likely to use
OCP but less likely to use condoms4. In this study, for
those who had 10 or more lifetime partners, regular condom use was
reported in only 21% of males and 7.5% of females. Overall, regular
condom use was reported in 24.8% of men and 15.6% of women.
- A 1994 study of American women at risk of HIV infection found
that consistent OCP users were significantly more likely to assess
their risk of HIV infection as "very unlikely" (73% vs.
58%), even after actual risk differences between groups had been
controlled for5. Beliefs about the effectiveness of a
method for pregnancy prevention may generalize to beliefs about its
efficacy for disease prevention.
- In 1995, a Brazilian study of female partners of HIV-positive
men found that oral contraceptive use was associated with a number
of risky behaviors. These included anal sex, lack of condom use
during anal sex, and high frequency of sexual contacts with a
partner. Use of OCP was also associated with factors that may
indicate a low perceived susceptibility to STD, such as no previous
STD and asymptomatic clinical stage of HIV in a
partner6.
Adolescents select pregnancy as the most worrisome
outcome of sexual intercourse
-
The Canada Youth and AIDS Study asked respondents which of AIDS,
STD and pregnancy they worried about most as a possible outcome of
sexual intercourse. Pregnancy was selected most often by all
groups, grade 11 students, dropouts, and college/university
students. Approximately 57% of Grade 11 students (male and female
combined) and 59.5% of college/university students selected
pregnancy as the most worrisome outcome of sexual intercourse.
Conversely, only 4% of both the grade 11 students and the
college/university students selected STD as the most worrisome
outcome7.
-
In 1992, a Norwegian study showed that the majority of
adolescents who use contraception (pills or condoms) do so for
protection against unintended pregnancy and not for protection
against STDs2. Use of OCP in this study was widespread
among adolescents with high frequency of sexual intercourse and few
sexual partners.
Serial monogamy does not protect against
STD
- Adolescents often engage in serial monogamy (a series of
monogamous relationships, one after the other), a practice that
generally results in a lower, and sometimes unrealistic, perceived
risk of STD and hence a lower perceived need for condoms against
STD2. Adolescents who practise serial monogamy perceive
the relationship as 'feeling safe' and feel that their
partner 'looks safe'.
- As partners become better known to each other, they are more
likely to stop condom use and switch to OCP since they both feel a
sense of trust and perceived safety from STD. Self-defined serial
monogamy contributes to this sense of safety5.
Education on the role of condoms in STD
prevention
- In 1996, an American study showed that receipt of an AIDS
education intervention was associated with more effective
contraceptive use and an understanding of the role of barrier
methods in STD prevention. After an AIDS education intervention,
more than 80% of a longitudinal study group of 383 African-American
youths from ages 9 to 15 reported using condoms along with oral
contraceptives8. This compared with a figure of
approximately 66% at baseline. Intervention youth were also more
likely to use barrier methods of birth control more
effectively.
- In Canada, several programs have been developed to address
sexual health education. Examples include Fisher and Fisher's
Information-Motivation-Behavior Skills Program, the condom and pill
campaigns (targeting health care providers) of Alberta Health, the
Skills for Healthy Relationships educational program, developed at
Queen's University, and the Guidelines for Sexual Health
Education. Evaluations of these programs have led to the conclusion
that they result in significant increases in condom use, decreases
in the number of partners, and postponement of first sexual
intercourse9.
References
- Laboratory Centre for Disease Control. Sexually transmitted
disease surveillance in Canada: 1995 annual report. CCDR
1998;24S1:1-32.
- Traeen B, Lewin B, Sundet JM et al. Use of birth control
pills and condoms among 17-19-year-old adolescents in Norway:
contraceptive versus protective behavior? AIDS Care
1992;4(4):371-80.
- Boroditsky R, Fisher WA, Sand M. Condoms: attitudes and
practices of Canadian women. The 1995 Canadian Contraception
Study. J Soc Obstet Gynecol Can (special supplement) December,
1996.
- MacDonald NE, Wells GE, Fisher WA et al. High-risk STD/HIV
behavior among college students. JAMA
1990;263(23):3155-9.
- Galavotti C, Schnell DJ. Relationship between contraceptive
method choice and beliefs about HIV and pregnancy prevention. Sex Transm Dis 1994;21(1):5-7.
- Guimares MD, Muñoz A, Boschi-Pinto C et al. HIV
infection among female partners of seropositive men in Brazil. Am J Epidemiol 1995;142(5):538-47.
- King A, Beazley R, Warren W et al. Canada Youth and AIDS
Study. Kingston: Queen's University, 1988.
- Stanton BF, Li X, Galbraith J et al. Sexually transmitted
diseases, human immunodeficiency virus, and pregnancy prevention:
combined contraceptive practices among urban African-American
adolescents. Arch Pediatr Adolesc Med 1996;150(1):17-24.
- Maticka-Tyndale E. Reducing the incidence of sexually
transmitted disease through behavioural and social change. Can
J Human Sexuality 1997;6(2):89-104.