Background: Previous research shows that sexual minority women have higher rates of unintended pregnancy than heterosexual women, but has not considered the wide range of contraceptive method effectiveness when exploring this disparity. We examine contraceptive use effectiveness and desire for pregnancy prevention information among college women across sexual orientation identity as a risk factor for unintended pregnancy. Methods: Using the National College Health Assessment Fall 2015 dataset, restricted to women who reported engaging in vaginal sex and not wanting to be pregnant (N = 6,486), logistic regression models estimated the odds of contraceptive method effectiveness and desire for pregnancy prevention information by sexual orientation. Results: Most women (57%) reported using a moderately effective contraceptive method (e.g., pill, patch, ring, shot) at last vaginal sex. Compared with heterosexual women, bisexual (adjusted odds ratio [aOR], 0.48; 95% confidence interval [CI], 0.37–0.62), lesbian (aOR, 0.03; 95% CI, 0.02–0.06), pansexual/queer (aOR, 0.38; 95% CI, 0.25-.56), and other (aOR, 0.50; 95% CI, 0.30–0.81) women were significantly less likely to have used a moderately effective method compared with no method. Only 9% of the sample used a highly effective method; asexual (aOR, 0.58; 95% CI, 0.37–0.92) and lesbian (aOR, 0.07; 95% CI, 0.03–0.20) women were significantly less likely than heterosexual women to have used these methods. Pansexual/queer and bisexual women were more likely than heterosexual women to desire pregnancy prevention information. Conclusions: Several groups of sexual minority women were less likely than heterosexual women to use highly or moderately effective contraceptive methods, putting them at increased risk for unintended pregnancy, but desired pregnancy prevention information. These findings bring attention to the importance of patient-centered sexual and reproductive care to reduce unintended pregnancy.