1. STDs among Sexually Active Female College Students: Does Sexual Orientation or Gender of Sex Partner(s) Make a Difference?
Lisa L. Lindley, DrPH, MPH, CHES
Dept Health Promotion, Ed. & Behavior
Arnold School of Public Health
Michelle Burcin, PhD, MPH, CHES
Director, Healthy Carolina
University of South Carolina

2. Background College students, esp. females, at risk for STDs:
Alcohol use, multiple sex partners (ACHA, 2007)
Immature cervix (Moscicki, Shiboski & Broering, 1998; Ho et al., 1998)
STD risk factors among lesbian and bisexual women:
Older age, substance use/IDU, # sex partners, vaginal intercourse w/men, earlier age 1st same-sex experience.
(Bailey et al., 2004; Carroll et al., 1997; Diamant, Lever & Shuster, 2000; Dolan & Davis, 2003; Marrazzo, 2000; Marrazzo et al., 1996, 2000, 2003, Lindley et al., In-press)
Few studies:
STD risk among college lesbian and bisexual women (Lindley et al., 2003, In-press)
Comparing STD risk by sexual orientation and gender of sex partners. (Bauer & Welles, 2001)

3. Purpose
To determine risk for STDs (past school year) among sexually active female college students based on self-reported sexual orientation and gender of sex partner(s) (past year).
Secondary analysis, National College Health Assessment (NCHA) (Spring 2006 data).

4. *Sexually active = 1+ sex partners (past year)
NCHA Spring 2006
123 postsecondary institutions
117 used random sampling
92 web-based, 22 paper, 3 both
4 year (96.6%), public (61.5%) colleges/universities
Total: 94,806 (Females: 57,903)
N = 29,952 sexually active* non-international females
*Sexually active = 1+ sex partners (past year)

5. Demographics Age Range: 18-24 years Mean Age: 20.4 yrs (SD=1.60)
Race/Ethnicity:
White %
Black %
Hispanic %
Asian/PI %
AI/AN %
Other %
Year in School

6. Measures: Sexual Orientation & Gender of Sex Partner(s)
Which of the following best describes you?
Heterosexual
Gay/Lesbian
Bisexual
Transgendered (Not included in the analyses)
Unsure
Within the last school year, were your sexual partner(s), if any:
N/A (Not included in the analyses)
Male
Female
Both Male and Female

7. Table 1: Sexual Orientation, Gender & # Sex Partners (past year)%
Heterosexual
28261
94.4
Gay/Lesbian
271
0.9
Bisexual
1000
3.3
Unsure
420
1.4
Gender of Sex Partners (past year)
Male
28728
95.9
Female
615
2.1
Both Male and Female
609
2.0
Number of Sex Partners (past year)
1 partner
19479
65.0
2 partners
5173
17.3
3-5 partners
4394
14.7
6+ partners
906
3.0

8. Table 1: Sexual Orientation, Gender & # Sex Partners (past year)%
Heterosexual
28261
94.4
Gay/Lesbian
271
0.9
Bisexual
1000
3.3
Unsure
420
1.4
Gender of Sex Partners (past year)
Male
28728
95.9
Female
615
2.1
Both Male and Female
609
2.0
Number of Sex Partners (past year)
1 partner
19479
65.0
2 partners
5173
17.3
3-5 partners
4394
14.7
6+ partners
906
3.0
Had 2+ partners n %
9691
92.5
193
1.8
589
5.6

9. Table 2: Gender of Sex Partner(s) (past year) by Sexual Orientation
Male (%)
Female (%)
Both Male & Female (%)
Heterosexual
28261
98.4
0.9
0.6
Gay/Lesbian
271
4.8
84.9
10.3
Bisexual
1000
55.7
9.7
34.6
Unsure
420
81.0
5.5
13.6

10. Measures: STD Diagnosis (past year)
Within the last school year, have you had any of the following:
Chlamydia
Genital herpes
Genital warts/HPV
Gonorrhea
HIV infection
STD Diagnosis = Diagnosed with one or more above.

11. Table 3: Percent reporting STD (past year) by Sexual Orientation
HPV/ warts
Chlamydia
Genital Herpes
Gonorrhea
HIV
1+ STD
Heterosexual
3.8
1.3
1.1
0.2
0.1
5.8
Gay/Lesbian
0.4
1.5
0.0
2.3
Bisexual
5.9
1.9
0.3
9.1
Unsure
5.0
0.7
1.2
6.3
Significance
p<.001 NS

12. Table 4: Percent reporting STD (past year) by Gender of Sex Partner(s) (past year)
HPV/ warts
Chlamydia
Genital Herpes
Gonorrhea
HIV
1+ STD
Male
3.7
1.3
1.0
0.2
0.1
5.7
Female
3.3
0.3
1.5
4.4
Both Male & Female
10.1
0.7
15.3
Significance
p<.001 NS

13. Table 5: Percent reporting STD (past year) by Gender of Sex Partner(s) (past year) (2+ partners)
HPV/ warts
Chlamydia
Genital Herpes
Gonorrhea
HIV
1+ STD
Male (2+)
5.4
2.4
1.2
0.4
0.1
8.7
Female (2+)
4.7
1.1
2.1
0.5
5.9
Both Male & Female
10.4
3.4
3.2
0.2
15.5
Significance
p<.001 NS

14. Table 6: Number & Percent Ever Engaged in Oral, Vaginal and/or Anal Intercourse by Sexual Orientation & Gender of Sex Partner(s) (past year)
Sexual Orientation
Oral Sex
N (%)
Vaginal Int.
Anal Int.
Heterosexual
(93.8)
(91.6)
6282 (22.2)
Gay/Lesbian
257 (94.8)
***198 (73.1)
87 (32.1)
Bisexual
**969 (96.9)
922 (92.2)
***434 (43.4)
Unsure
394 (93.8)
373 (88.8)
140 (33.3)
Gender of Partners
Male
(93.8)
26321 (91.6)
6483 (22.6)
Female
579 (94.1)
***486 (79.0)
168 (27.3)
Both Male & Female
***597 (98.0)
574 (91.4)
***292 (47.9)
Overall
28136 (93.9)
27381 (91.4)
6943 (23.2)
*p<.05; **p<.01; ***p<.001

15. Condom Last Vaginal Int.
Table 7: Number & Percent Used Condom last Oral, Vaginal and/or Anal Intercourse by Sexual Orientation & Gender of Sex Partner(s) (past year)
Sexual Orientation
Condom Last Oral Sex
N (%)
Condom Last Vaginal Int.
Condom Last Anal Int.
Heterosexual
774 (3.0)
(52.7)
1364 (23.2)
Gay/Lesbian
**13 (5.3)
***50 (26.7)
19 (26.4)
Bisexual
24 (2.5)
457 (50.1)
**126 (29.6)
Unsure
**20 (5.2)
203 (55.3)
**40 (30.1)
Gender of Partners
Male
794 (3.0)
(52.7)
1418 (23.3)
Female
21 (3.7)
***189 (40.5)
38 (27.0)
Both Male & Female
16 (2.7)
298 (52.3)
**93 (32.5)
Overall
831 (3.0)
14181 (52.5)
1549 (23.8)
*p<.05; **p<.01; ***p<.001

16. Table 8: Mean Number of Sex Partner(s) (past year) by Sexual Orientation and Gender of Sex Partners
Mean (SD)
Overall
29952
1.8 (1.72)
Sexual Orientation***
Heterosexual
28261
1.7 (1.53)
Gay/Lesbian
271
2.0 (2.29)
Bisexual
1000
2.8 (3.70)
Unsure
420
2.5 (3.80)
Gender of Partners***
Male
28728
1.7 (1.57)
Female
615
1.7 (1.87)
Both Male & Female
609
4.5 (4.19)
***p<.001

17. Table 8: Mean Number of Sex Partner(s) (past year) by Sexual Orientation and Gender of Sex Partners
Mean (SD)
Overall
29952
1.8 (1.72)
Sexual Orientation***
Heterosexual
28261
1.7 (1.53)
Gay/Lesbian
271
2.0 (2.29)
Bisexual
1000
2.8 (3.70)
Unsure
420
2.5 (3.80)
Gender of Partners***
Male
28728
1.7 (1.57)
Female
615
1.7 (1.87)
Both Male & Female
609
4.5 (4.19)
Had 2+ partners*** N
Mean (SD)
9691
3.1 (2.07)
193
3.2 (2.78)
589
4.6 (4.79)
***p<.001

18. Table 9: Mean Number of Sex Partner(s) (past year) by Gender of Sex Partners (past year) among Bisexual College Women
Gender of Partners*** N
Mean (SD)
Male
557
2.0 (2.72)
Female 97
1.2 (0.62)
Both Male & Female
346
4.6 (4.77)
***p<.001

19. Table 9: Mean Number of Sex Partner(s) (past year) by Gender of Sex Partners (past year) among Bisexual College Women
Had 2+ partners***
Gender of Partners*** N
Mean (SD)
Male
557
2.0 (2.72)
Female 97
1.2 (0.62)
Both Male & Female
346
4.6 (4.77) N
Mean (SD)
204
3.6 (3.98) 14
2.5 (0.88)
337
4.6 (4.79)
***p<.001

20. Table 10: Had a routine gynecological exam (past year) by Sexual Orientation and Gender of Partners%
Heterosexual
28108
72.7
Gay/Lesbian
269
46.1
Bisexual
998
65.8
Unsure
418
64.1
Gender of Partners***
Male
28605
72.5
Female
580
54.0
Both Male and Female
608
73.2
***p<.001

21. Table 11: Odds of STD diagnosis (past year) by Sexual Orientation
OR (95% CI)
Heterosexual
1.00 (Referent)
Gay/Lesbian
*0.38 (0.17, 0.85)
Bisexual
***1.59 (1.27, 1.99)
Unsure
1.12 (0.75, 1.66)
***4.24 (1.83, 9.79)
*2.97 (1.21, 7.30)
0.70 (0.45, 1.10)
*p<.05; **p<.01; ***p<.001

22. Table 11: Odds of STD diagnosis (past year) by Sexual Orientation
Had Routine Gyn Exam
Sexual Orientation
OR (95% CI)
Heterosexual
1.00 (Referent)
Gay/Lesbian
*0.38 (0.17, 0.85)
Bisexual
***1.59 (1.27, 1.99)
Unsure
1.12 (0.75, 1.66)
***4.24 (1.83, 9.79)
*2.97 (1.21, 7.30)
0.70 (0.45, 1.10)
OR (95% CI)
1.00 (Referent)
*0.32 (0.10, 1.00)
***1.73 (1.37, 2.20)
1.01 (0.64, 1.59)
**5.44 (1.69, 17.51)
3.16 (0.92, 10.84)
*0.58 (0.35, 0.97)
*p<.05; **p<.01; ***p<.001

23. Table 12: Odds of STD diagnosis (past year) by Gender of Sex Partner(s) (past year)
OR (95% CI)
Male
1.00 (Referent)
Female
0.57 (0.17, 1.92)
Both Male & Female
***3.64 (2.28, 5.83)
**6.36 (1.94, 20.78)
*p<.05; **p<.01; ***p<.001

24. Table 12: Odds of STD diagnosis (past year) by Gender of Sex Partner(s) (past year)
Had 2+ partners
Gender of Sex Partners
OR (95% CI)
Male
1.00 (Referent)
Female
0.57 (0.17, 1.92)
Both Male & Female
***3.64 (2.28, 5.83)
**6.36 (1.94, 20.78)
OR (95% CI)
1.00 (Referent)
0.66 (0.36, 1.23)
***1.92 (1.52, 2.44)
**2.90 (1.51, 5.55)
*p<.05; **p<.01; ***p<.001

25. Table 12: Odds of STD diagnosis (past year) by Gender of Sex Partner(s) (past year)
Had 2+ partners
2+ part/gyn exam
Gender of Sex Partners
OR (95% CI)
Male
1.00 (Referent)
Female
0.57 (0.17, 1.92)
Both Male & Female
***3.64 (2.28, 5.83)
**6.36 (1.94, 20.78)
OR (95% CI)
1.00 (Referent)
0.66 (0.36, 1.23)
***1.92 (1.52, 2.44)
**2.90 (1.51, 5.55)
OR (95% CI)
1.00 (Referent)
0.73 (0.35, 1.52)
***2.04 (1.59, 2.62)
**2.78 (1.30, 5.96)
*p<.05; **p<.01; ***p<.001

26. Discussion
First large-scale national sample examining STD risk among sexually active female college students by SO and GoP.
Bisexual women were at greatest risk for STD; gay/lesbian women were at least risk.
However, lesbians (and WSW) were significantly less likely to have had a routine gynecological exam (past year).
Equally important to note that not all bisexual students at high risk.
Independent of sexual orientation, greatest STD risk was among women who had sex with both males and females (past year).
35% bisexual, 14% unsure, 10% gay/lesbian, and <1% heterosexual.

27. Limitations Cross-sectional data.
Multiple data collection methods, especially web-based.
Self-selection bias.
Self-reported data:
Sexual behaviors (with no definitions; e.g. “vaginal intercourse”)
STD diagnoses (“had”/past year only)
Coding scheme (sex w/males & females) created high-risk group.
Is greater risk due to gender of partners, number of partners, or combination of both?

28. Implications
Additional research needed to better understand sub-population of WSWM and factors associated with elevated risk taking.
Vital that college and sexual health professionals understand difference between sexual orientation, identity and behavior.
When assessing STD risk, focus on behaviors rather than identity or orientation.
Educational efforts targeting lesbians/WSW must address behavioral risk for STD, safer sex practices, and importance of regular gynecological exams (Pap tests).
Additional research needed to understand why young lesbians/ WSW do not seek routine gynecological exams.