Final answer:
The non-contraceptive benefits of COC use include a decrease in iron-deficiency anemia, ovarian cancer, and pelvic inflammatory disease (PID), but not in cervicitis.
Step-by-step explanation:
The question concerns the non-contraceptive benefits associated with the use of Combined Oral Contraceptives (COCs) and which condition is not decreased by COC use. The benefits of COC use do not include a decrease in cervicitis. While COCs have been associated with a reduced risk of conditions such as iron-deficiency anemia, ovarian cancer, and pelvic inflammatory disease (PID), the literature does not attribute a reduction in cervicitis to the use of COCs. In fact, some of the non-contraceptive benefits of COCs include a decreased risk of ovarian and endometrial cancers and protection against PID, which is an infection of the female reproductive organs typically caused by sexually transmitted bacterial pathogens.