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Author Manuscript
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Published in final edited form as:
AIDS Educ Prev. 2010 October ; 22(5): 455–465. doi:10.1521/aeap.2010.22.5.455.
Condom Access: Associations with Consistent Condom Use
among Female Sex Workers in Two Northern Border Cities of
Mexico
Fátima A. Muñoz, MD1, Robin A. Pollini, PhD1, María Luisa Zúñiga, PhD1, Steffanie A.
Strathdee, PhD1, Remedios Lozada, MD2, Gustavo A. Martínez, MD3, Ana M. VallesMedina, MPH4, Nicole Sirotin, MD1, and Thomas L. Patterson, PhD5
1Division of Global Public Health, School of Medicine, University of California, San Diego
2Patronato
Pro-COMUSIDA, Tijuana, Mexico
3Community
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Health & Development of Ciudad Juarez (SADEC) and Mexican Federation of
Private Associations (FEMAP), Ciudad Juarez, Chihuahua, Mexico
4Master
in Public Health Program, Autonomous University of Baja California, Tijuana, Mexico
5Department
of Psychiatry University of California, San Diego and MIRECC, VA Medical Center,
San Diego, California
Abstract
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To determine whether condom access is associated with consistent condom use among FSWs in
Tijuana and Ciudad Juarez, between 2004 and 2006 we administered a questionnaire to 924 FSWs
who reported unprotected sex with a client in the past two months. Of these women, 43% reported
consistent (“often” or “always”) condom use; 74% said condoms were available; and 38%
reported having access to free condoms. In a logistic regression, factors positively associated with
consistent condom use were condom availability (AdjOR = 2.00; 95% CI: 1.32–3.03), condom
affordability (AdjOR = 1.72; 95% CI: 1.25–2.38) and self–efficacy (AdjOR = 2.16; 95% CI: 1.54–
3.04). Factors inversely associated with consistent condom use included poor financial status
(AdjOR = 0.65; 95% CI: 0.47–0.90), methamphetamine use (AdjOR = 0.58; 95% CI: 0.40–0.83),
alcohol use (AdjOR = 0.68; 95% CI: 0.49–0.96), and recent injection drug use (AdjOR = 0.62;
95% CI: 0.39–0.97). While increased condom availability may improve condom use among FSWs
in general, interventions to broaden condom use among lower-income and drug-using FSWs are
critically needed.
Keywords
female sex workers; condom use; prevention; HIV/AIDS; behavioral interventions; Mexico
According to the United Nations Program on HIV/AIDS (UNAIDS), unprotected sex is the
main vehicle of HIV transmission in Mexico and Latin America (Cohen, 2006; ONUSIDA,
2008). In 2008, the Mexican state of Chihuahua, where Ciudad Juarez is located, ranked
fifth nationally with an HIV prevalence of 0.5%, while Baja California, where Tijuana is
located, ranked 7th at 0.4%; both rates stand well above Mexico’s national prevalence of
0.3% (CENSIDA, 2008).
Corresponding Author: Thomas L. Patterson, Mail Code 0680, 9500 Gilman Drive, La Jolla, CA 92093-0680. Telephone: (858)
534-3354. FAX: (858) 534-7723. tpatterson@ucsd.edu.
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The sex work industry thrives in many cities of northern Mexico, with female sex workers
(FSWs) frequently servicing clients from both the United States and Mexico. FSWs are
considered a high risk group for acquiring and transmitting HIV (Jimenez, Lara, & Rosado,
2001; Patterson, Semple, et al., 2008), and HIV prevalence among FSWs in the Mexico–
U.S. border region is increasing. In 1997, only 0.6% of FSWs tested positive for HIV (del
Rio & Sepúlveda, 2002); by 2008, 6.0% tested positive (Patterson, Semple, et al., 2008).
Factors such as low socioeconomic status, migration, low education levels, drug use, and
knowledge and perceptions about HIV and condom use all have been linked to risky sexual
behaviors among FSWs (Basuki et al., 2002; Cohen, 2006; Dandona et al., 2005; Jimenez et
al., 2001; Patterson et al., 2006b; Rhodes et al., 2007; Strathdee, Lozada, Semple, et al.,
2008). However, condom access also plays a role, particularly in developing countries,
because FSWs must have access to condoms in order to use them consistently (Morris,
Morris, & Ferguson, 2009).
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Consistent condom use plays a vital role in preventing sexual transmission of HIV and has
consequently become the primary focus of interventions targeting vulnerable groups such as
FSWs (Cohen, 1999; Kayembe et al., 2008; ONUSIDA, 2001; Zhao, Wang, Fang, Li, &
Stanton, 2008). In Mexico, the Secretariat of Health, through the national HIV/AIDS
program, promotes condom use and provides free condoms at community health centers, but
these programs cannot ensure access to condoms for sex workers who do not attend these
centers. In a recent behavioral intervention to promote condom use among FSWs in Tijuana
and Ciudad Juarez, Mexico, of the 924 FSWs who completed the study, the intervention
group had a 40% lower cumulative HIV/STI incidence after six months of follow-up, which
was significantly lower than the control group. Incidence density for the intervention vs.
control was 13.8 vs. 24.92 per 100 person years (py) for STIs combined, and 0 vs. 2.01 per
100 py for HIV, with concomitant increases in total numbers and percentages of protected
sex acts and decreases in total numbers of unprotected sex acts with clients (Patterson,
Mausbach, et al., 2008). Another study in Louisiana showed that a condom social marketing
intervention improved condom use by increasing condom distribution and availability
(Cohen et al., 1999).
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Lack of access to condoms has become a significant barrier to safer sexual practices,
particularly in developing countries (Cohen, 1999; Little, Myer, & Mathews, 2002; Myer,
Mathews, & Little, 2002). Some persons with low income rely upon free condoms and use
them to engage in sexual services to fulfill economic needs; for them, limited access leads to
high-risk behavior (Little et al., 2002; Rhodes et al., 2007; Sunmola, Adebayo, &
Ogungbemi, 2008). Individuals who both purchase condoms and can obtain them free of
charge may report more consistent condom use than those who rely on purchase alone
(Sunmola et al., 2008); however, in developing countries, low availability of condoms has
been associated with unprotected sexual practices (Morris et al., 2009).
Other barriers to condom use that specifically affect FSWs should also be taken into
account. Clients’ demands; poor condom negotiation skills; higher pay for unprotected sex;
lack of knowledge about HIV; and negative attitudes toward condom use may also
significantly hinder FSWs’ adoption of safer sex practices (Bucardo, Semple, Fraga-Vallejo,
Davila, & Patterson, 2004; Eva, Munakata, & Onuoha, 2007; Garcia, Yam, & Firestone,
2006; Ntumbanzondo, Dubrow, Niccolai, Mwandagalirwa, & Merson, 2006). Few studies
have examined the association between condom access and condom use while controlling
for these factors, particularly in low and middle income countries where there is a close
relationship between sex work and HIV transmission (Kayembe et al., 2008). In this study,
we examine the association between condom access and consistent condom use among
FSWs in Tijuana and Ciudad Juarez, Mexico.
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METHODS
STUDY SETTINGS
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The data for this analysis were taken from a multi-site, randomized trial of a condom-use
intervention (Patterson, Mausbach, et al., 2008). The first phase of the intervention study
was conducted in two cities, Tijuana and Ciudad Juarez, between 2004 and 2006. Tijuana is
the largest city in the state of Baja California, Mexico, and is situated on the U.S. border
adjacent to San Diego, California. Tijuana, one of Mexico’s fastest growing cities, had a
population of 1,410,700 in 2005; roughly half of Baja California’s population lives in
Tijuana (INEGI, 2005), although over half of Tijuana’s inhabitants were born outside the
state. The Tijuana–San Diego border crossing has become one of the busiest in the world,
with over 48.6 million people crossing in 2007 (SANDAG, 2007). Sex work is quasi-legal in
Tijuana, and researchers estimate that between 4,850 and 9,000 registered sex workers
operate in the city (Brouwer et al., 2006). Not surprisingly, Tijuana is also a common
destination for sexual tourism, especially among U.S. residents.
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Ciudad Juarez is located in the Mexican state of Chihuahua, across the U.S. border from El
Paso, Texas. In 2005, it had a population of 1,313,338, with 36% of its residents reporting
that they were born outside Chihuahua (INEGI, 2005). In 2007, a reported 32.4 million
people crossed the border from Ciudad Juarez to El Paso. In Ciudad Juarez as in Tijuana,
sex work is quasi-legal, and an estimated 4,000 FSWs work in the city (Patterson et al.,
2006b).
STUDY POPULATION
Between January 2004 and January 2006, 924 FSWs were recruited into a behavioral
intervention study intended to increase condom use in Tijuana and Ciudad Juarez (Patterson
et al., 2006a). Outreach workers approached women in the zona roja (red light district) of
each city, and women who expressed interest in participating in a safer-sex study answered a
series of screening questions to establish their eligibility. Women could also learn about the
study from municipal or community health clinics and present themselves at the study office
for screening. A number of “red herring” questions were included in the screener to make
the eligibility criteria less easy to guess. The eligibility criteria included being at least 18
years of age; having exchanged sex for drugs, money or other commodities within the past 2
months; and having had unprotected vaginal or anal sex with at least one client within the
past four weeks. All study participants provided written informed consent prior to giving
data. Women were excluded if they reported that they had previously tested HIV-positive.
DATA COLLECTION
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Trained, Spanish-speaking, female counselors administered the baseline survey face-to-face
in private clinic rooms or outreach offices (Patterson et al., 2006a). The structured
questionnaire took approximately 35 to 40 minutes to complete. Interview variables
included sexual risk behaviors, working conditions, financial need, use of alcohol and drugs,
social support, social influence, life experiences, social cognitive factors, and
sociodemographics. Behavioral outcomes were also assessed, including frequency of
unprotected sex with clients, number of clients, number of sex partners who inject drugs,
and how much money the participant earned per sex act with and without a condom. Study
protocols were reviewed and approved by institutional review boards in San Diego, Tijuana,
and Ciudad Juarez. Participants were compensated US$30 the baseline visit and US$30 for
the six-month follow-up visit.
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STATISTICAL ANALYSIS
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The primary outcome variable in this study was consistent condom use by FSWs with their
clients. Participants used a scale (never, sometimes, often, always) to report how often they
used a condom for vaginal sex with clients. These values were collapsed to create a binary
outcome for consistent (always or often) vs. inconsistent (never or sometimes) condom use
with clients. Because one of the eligibility criteria for the intervention study was having had
unprotected sex (either vaginal or anal) with a client at least once in the past four weeks, it
was predictable that only a very small number of participants would endorse “always” using
a condom with a client for vaginal sex (presumably those women whose eligibility for the
study was established by their having had unprotected anal rather than vaginal sex with a
client in the past four weeks). In fact, only 26 participants (3% of the sample) stated that
they “always” used a condom for vaginal sex with clients, so that the subsample of
“consistent” condom users consisted mainly of women who stated that they use condoms
“often” for vaginal sex with clients. Given this binary outcome, we examined the extent to
which FSWs with consistent and inconsistent condom use with clients differed in the
following five domains: (1) sociodemographics; (2) social environment, including financial
situation, working conditions, client characteristics (e.g. nationality, drug use), number of
clients, and main work venue (e.g., brothel, street, bar); (3) condom access, including
whether they could afford their own condoms or had access to free ones; (4) use of alcohol
and illicit drugs, including whether drugs and alcohol were used before or during sex with
clients; and (5) perceptions and beliefs about condom use, including a five-item self-efficacy
measure for proper use of condoms with clients (e.g. “I can use a condom properly”); and a
five-item outcome expectancies measure on the benefits of using condoms (e.g. “I believe
that condoms will protect me from catching HIV”). Responses to both of these measures
were on a four-point scale ranging from 1 (strongly disagree) to 4 (strongly agree). The
alpha for the self-efficacy scale for this sample was 0.85; that for the outcome expectancies
scale was 0.79 (Patterson et al., 2006a).
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Baseline data were analyzed to compare FSWs who reported consistent condom use with
those who did not. Continuous variables were examined using the Wilcoxon rank sum test,
while categorical data were examined using Fisher exact tests or chi-square tests. Logistic
regression was used to identify factors associated with consistent condom use. Multivariate
models were developed by a manual procedure according to which all variables of interest
that attained a significance level of <10% were considered stepwise, beginning with those
with the highest p-value. The likelihood ratio test was used to compare nested models, using
a significance level of 5% to select variables for inclusion in the final model. We also
explored interactions between variables in the final model, including interactions by site.
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RESULTS
The study enrolled a total of 924 FSWs (474 in Tijuana and 450 in Ciudad Juarez). In
comparing participants from Tijuana and Ciudad Juarez (Table 1), we found significant site
differences for age, marital status, whether they had only Mexican or also some U.S. clients,
main work venue, methamphetamine use in the last month, and lifetime use of cocaine.
Median age was 32 years; most participants (87%) were born outside the state in which they
participated in the study. About one-fourth (24%) were married or reported living in
common-law relationships, and the majority (94%) had children. In terms of work
environment, FSWs were most likely to report working on the street (44%) rather than in a
bar (35%). The majority (91%) reported sex work as their main source of income; one-third
of the FSWs (36%) considered their financial situation “bad,” 55% reported “neither good
nor bad,” and a lower percentage (9%) considered their financial situation “good.” Almost
all (95%) attributed their involvement in sex work to financial need.
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Three-quarters of FSWs (74%) reported having condoms available every time that they had
vaginal sex with clients; 69% said they could afford to buy their own condoms (average cost
of a condom in Ciudad Juarez and Tijuana is 14–16 pesos (about US$1). Access to free
condoms was limited, with a low percentage (6%) reporting getting free condoms “always,”
4% reporting “often,” 28% “sometimes,” and 62% “never.”
Use of alcohol in the past month was reported by a majority of FSWs (73%). The illicit drug
that was most frequently used in the last month was methamphetamine (endorsed by 21% of
participants), followed by cocaine (20%), marijuana (19%), and heroin (14%). Significant
numbers of participants also reported using alcohol (59%) and illicit drugs (32%) before or
during sexual encounters with clients.
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Table 1 also compares the characteristics of FSWs who reported consistent condom use with
clients (43%) and those who did not (57%). Consistent condom users (n = 401) were more
likely to be married or living in common-law relationships (29% vs. 20%, p = 0.004), report
having access to condoms (87% vs. 65%, p < 0.001), be able to buy their own condoms
(79% vs. 62%, p < 0.001), and have U.S. clients (31% vs. 23%, p = 0.006). FSWs who
reported consistent condom use were also significantly more likely to demonstrate higher
self-efficacy regarding condom use with clients, including using condoms properly (93% vs.
85%, p < 0.001), using condoms every time they had vaginal or anal sex (97% vs. 83%, p <
0.001), and using condoms while under the influence of drugs (80% vs. 66%, p < 0.001).
FSWs who reported consistent condom use were also significantly less likely to report being
in a bad financial situation (28% vs. 41%, p < 0.001) (Table 1).
In the final multivariate model (Table 2), after controlling for significant potential
confounders among the demographic variables shown in Table 1 (i.e., place of birth, marital
status, and education), a number of factors were independently associated with consistent
condom use. Those positively associated with consistent condom use were having access to
condoms (AdjOR = 2.12, 95% CI: 1.38–3.25), being able to afford condoms (AdjOR = 1.57,
95% CI: 1.12–2.20), self-efficacy regarding condom use per unit increase in score (AdjOR =
2.16, 95% CI: 1.54–3.04) and lifetime use of cocaine (AdjOR = 1.46, 95% CI: 1.06–2.02).
Factors independently but negatively associated with consistent condom use were being in a
bad financial situation (AdjOR = 0.65, 95% CI: 0.47–0.89), having used methamphetamine
at least once in one’s lifetime (AdjOR = 0.68, 95% CI: 0.40–0.83), having used alcohol in
the past month (AdjOR = 0.68, 95% CI: 0.49–0.96), and using injected drugs within the last
month (AdjOR = 0.62, 95% CI: 0.39–0.97). No significant interactions were observed.
DISCUSSION
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Our study of FSWs in Tijuana and Ciudad Juarez indicates that fewer than half of these
women used condoms consistently with clients. We found that condom availability, condom
affordability, and condom use self-efficacy were independently and positively associated
with consistent condom use with clients. One of the most important findings to emerge from
these data was the strong link between condom availability and use of condoms with clients.
Specifically, we observed that for FSWs in Tijuana and Ciudad Juarez, it was more
important to have condoms available than to get them for free. Perhaps for this reason, we
also found an association between consistent condom use and being able to afford condoms.
From a behavioral intention perspective, it is reasonable to hypothesize that availability
serves as a proxy for intention, in that study participants who reported condom availability
may have had condoms available precisely because they took measures to ensure that
availability prior to need.
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These results are consistent with those of studies performed in Indonesia (Basuki et al.,
2002), India (Dandona et al., 2005), Republic of Congo (Kayembe et al., 2008), Ghana
(Adu-Oppong, Grimes, Ross, Risser, & Kessie, 2007), Kenya (Morris et al., 2009) and
Louisiana (Bedimo, Pinkerton, Cohen, Gray, & Farley, 2002; Cohen & Farley, 2004; Cohen
et al., 1999). These studies all found that access to condoms was a major predictor of safe
sexual practices. These studies also documented an association between low prevalence of
condom use and lack of access. According to the literature that supports our findings, even
where purchasing condoms is not a problem (Sunmola et al., 2008), affordability is of little
help unless FSWs have access to condoms at the moment they are needed. Lack of access to
condoms leads FSWs to unprotected sexual practices with their clients, and this predicament
is more probable among women who work on the streets (Gu et al., 2008). Larios et al.
(2009), in a different study of our sample, found that rates of unprotected sex for FSWs who
work in the street (compared to those who work in bars) were disproportionately affected by
lack of access to condoms. Our study also shows that FSWs whose main work venue is the
streets report slightly less consistency in condom use compared to women who work in bars
and hotels. Taken together, these findings indicate that workplace venues are important
areas of future research inquiry and that providing greater access to condoms allows for
higher rates of protected sex acts (Adu-Oppong et al., 2007; Nai-Ying et al., 2008).
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Our findings on ability to afford condoms are consistent with those of other studies that have
shown an association of affordability with consistent condom use, an association that is even
more important than that between consistent condom use and the availability of free
condoms (Sunmola et al., 2008). However, in contrast with studies that found an association
between obtaining free condoms and consistent condom use (Adu-Oppong et al., 2007;
Cohen, 1999; Drezin, MA, & K, 2006; Kumar et al., 2006; Nai-Ying et al., 2008), we found
no such significant association among FSWs in Tijuana and Ciudad Juarez. In Mexico, some
prevention programs distribute free condoms; however, our study findings indicate that this
is insufficient for ensuring consistent condom use among FSWs in the two cities that we
studied.
We found an independent association between higher levels of self-efficacy for using
condoms and consistent condom use with clients. This finding is consistent with other
studies (Gu et al., 2008; Knipper et al., 2007; Patterson, Mausbach, et al., 2008; Villarruel,
Jemmott, Jemmott, & Ronis, 2004) that have demonstrated that self-efficacy to use a
condom is correlated with lower sexual risk and is particularly predictive of condom use.
Increasing condom self-efficacy through motivational interventions appears to be effective
as well in increasing consistent condom use among FSWs.
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Our study also found that the self-perception of being in a bad financial situation, having
ever used methamphetamine, having used alcohol in the past month, and injecting illegal
drugs in the past month were all independently and negatively associated with consistent
condom use in the FSWs in our sample. Previous studies in Tijuana and Ciudad Juarez
(Bucardo et al., 2004) and other cities (Dandona et al., 2005; Gu et al., 2008; Gutierrez,
Molina-Yepez, Morrison, Samuels, & Bertozzi, 2006; Nemoto et al., 2008) have shown that
financial difficulty can be a major reason for women to begin sex work, whereas other
researchers have reported that some women are pressured by family or by the use of drugs to
participate in risky sexual behaviors in exchange for money. FSWs often earn more money
for having sex without condoms, as has been mentioned in previous studies targeting the
same population (Strathdee, Philbin, et al., 2008).
Numerous studies have demonstrated an association between substance use and risky sexual
behavior (Eldemire-Shearer & Bailey, 2008; Morgenstern et al., 2009; Patterson, Semple, et
al., 2008). In accordance with previous findings, the use of illicit drugs is associated with
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inconsistent condom use (Gu et al., 2008; Morgenstern et al., 2009; Strathdee, Philbin, et al.,
2008). In our study, use of injected drugs and use of methamphetamine were both negatively
associated with consistent condom use. Methamphetamine use is very common among
FSWs in Tijuana (Patterson, Semple, et al., 2008), and it can affect the central nervous
system, causing impaired judgment and higher-risk sexual behaviors (Corsi & Booth, 2008;
Rusch et al., 2009).
Interestingly, we found a positive association between lifetime cocaine use and consistent
condom use. We expect this association is due to the higher association between both
lifetime cocaine use and condom use with residence in Ciudad Juarez (vs. Tijuana), an
association that persisted even after we controlled for recruitment site. It may also be that
past cocaine use is associated with another risk variable that is not sufficiently controlled for
in our model.
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Limitations of our study include inability to measure sexual behaviors with clients directly,
particularly the extent to which FSWs exchanged sex for drugs rather than for money, which
has been reported elsewhere (Inciardi, 1995; McMahon, Tortu, Pouget, Hamid, & Neaigus,
2006; Strathdee, Lozada, Ojeda et al., 2008). Another limitation to consider is that condom
availability was based on self-report and that “consistent condom use” in this study
comprised both “often” and “always.” Certainly “always” using a condom is the desired
behavioral outcome for primary prevention of HIV transmission; however, in light of the
very high risk behavior reported by our study population, “often” using a condom is a step in
the right direction and may be viewed as a success.
Since participants were recruited through convenience sampling and because higher-risk
women were selected by design, our findings may not reflect the experience of other FSWs
and are likely not representative in each city.
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The relationships we observed between drug use behaviors and consistency of condom use
among FSWs are important and should be further investigated. Intensified behavioral
interventions could be implemented to promote condom use among high risk FSW
subgroups, although some aspects, such as FSWs’ poor economic status, would be difficult
to alleviate. Greater access to drug and alcohol treatment may help by intervening upon the
relationship between drug dependence and lower condom use. Understanding which types of
client exert more pressure and are willing to pay more for sex without condoms could
uncover avenues for interventions focused on clients. Further, our data emphasize the need
to enhance both condom availability and FSWs’ access to condoms. Condoms can be made
more readily available in bars, motels, and restrooms, to optimize their use. Moreover, our
findings add to the existing evidence of the value of motivational interventions for
enhancing FSWs’ self-efficacy, since self-efficacy is associated with consistent condom use
in this population.
Acknowledgments
Funding Sources
The study that yielded the data for this paper was supported by NIH R01 MH065849 (Patterson). Certain individual
co-authors were also supported by the following NIH grants: R25 DA025571 (Muñoz); K01 DA022923 (Pollini);
R01 DA023877 (Strathdee); K01 MH072353-05 (Zúñiga).
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Table 1
Baseline Characteristics
Total
(n = 924)
Always or often
use condom
(n = 401)
Never or sometimes
use condom
(n = 523)
p-value
32 (26,39)
32 (26,38)
33 (27,40)
0.056
54 (6%)
14 (4%)
40 (8%)
0.008
Muñoz et al.
Participant sociodemographic and risk characteristics
Demographics
Median age (years) (IQR)
AIDS Educ Prev. Author manuscript; available in PMC 2011 October 1.
Born in study location:
Tijuana
61 (7%)
33 (8%)
28 (5%)
Years lived in study city (IQR)
Ciudad Juarez
13 (5,25)
12 (5,24)
14 (6,27)
0.103
Married or living with common-law spouse
222 (24%)
115 (29%)
107 (20%)
0.004
6 (4,8)
6 (5,9)
6 (4,8)
0.033
Had children
862 (94%)
370 (92%)
492 (95%)
0.110
Speak English
181 (20%)
85 (21%)
96 (19%)
0.300
411 (44%)
170 (42%)
241 (46%)
0.209
Educational attainment (Years) (IQR)
Social Environment
Main workplace
Street
Bar or cantina
325 (35%)
131 (33%)
194 (37%)
0.163
Hotel or other
188 (21%)
100 (25%)
88 (17%)
0.002
Bad financial situation
328 (36%)
114 (28%)
214 (41%)
< 0.001
Financial need drives sex work
881 (95%)
379 (96%)
502 (96%)
0.372
Condom availability
683 (74%)
347 (87%)
336 (65%)
< 0.001
Can afford to buy own condoms
634 (69%)
316 (79%)
318 (62%)
< 0.001
Never
570 (62%)
244 (61%)
326 (63%)
0.001
Sometimes
258 (28%)
100 (25%)
158 (30%)
Obtain free condoms:
Often
40 (4%)
20 (5%)
20 (4%)
Always
55 (6%)
37 (9%)
18 (3%)
Had Mexican Clients
810 (88%)
341 (86%)
469 (90%)
0.034
Had US Clients
248 (27%)
126 (31%)
122 (23%)
0.006
Had clients who used drugs
676 (73%)
294 (73%)
382 (73%)
0.925
Had clients who injected drugs
292 (32%)
118 (30%)
174 (33%)
0.208
Smoked marijuana in the last month
173 (19%)
79 (20%)
94 (18%)
0.502
Used heroin in the last month
130 (14%)
49 (12%)
81 (16%)
0.158
Drug and alcohol use
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Always or often
use condom
(n = 401)
Never or sometimes
use condom
(n = 523)
p-value
Used cocaine in the last month
181 (20%)
Ever used methamphetamine
282 (31%)
104 (26%)
77 (15%)
< 0.001
104 (26%)
178 (34%)
0.008
Used methamphetamine in the last month
Used alcohol in the last month
197 (21%)
73 (18%)
124 (24%)
0.043
673 (73%)
280 (71%)
393 (76%)
0.072
Injected illegal drugs in the past month
114 (12%)
Used alcohol during or before sex
546 (59%)
52 (12%)
62 (12%)
0.167
225 (56%)
321 (61%)
0.116
Used illegal drugs during or before sex
297 (32%)
135 (34%)
162 (31%)
0.393
Muñoz et al.
NIH-PA Author Manuscript
AIDS Educ Prev. Author manuscript; available in PMC 2011 October 1.
Baseline Characteristics
Total
(n = 924)
FSW beliefs about condom use
I can use condom properly
817 (89%)
372 (93%)
445 (85%)
< 0.001
I can use condom every time I have vaginal or anal sex
819 (89%)
387 (97%)
432 (83%)
< 0.001
I can use condoms under influence of drugs
664 (72%)
319 (80%)
345 (66%)
< 0.001
Condoms protect me against HIV
807 (88%)
359 (90%)
448 (86%)
0.099
Condoms interfere with sexual pleasure
518 (56%)
243 (61%)
275 (53%)
0.016
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Table 2
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Factors independently associated with consistent condom use among female sex workers in two Northern
Cities in Mexico
Variable*
Availability of condoms (yes vs. no)
Adjusted Odds
Ratio
95% Confidence
Interval
2.12
1.38–3.25
Can afford their own condoms
1.57
1.12–2.20
Self-efficacy to use of condom (per unit increase)
2.16
1.54–3.04
Bad financial situation (yes vs. no)
0.65
0.47–0.89
Had ever used cocaine
1.46
1.06–2.02
Had ever used methamphetamine
0.68
0.40–0.83
Used alcohol in the past month
0.68
0.49–0.96
Injected illegal drugs in the past month
0.62
0.39–0.97
*
The following variables that were significant in univariate analyses were controlled for in the multivariate analyses: birthplace (inside or outside
of the study city), marital status, and years of education.
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