Which myoma type is primarily located on the outer surface of the uterus?

Subserosal myomas are primarily located on the outer surface of the uterus. These fibroids develop beneath the serosal outer layer and can extend outward, often creating a bulge on the outside of the uterine wall. This positioning can sometimes lead to changes in the shape of the uterus and may cause discomfort or pressure symptoms, depending on their size and location.

In contrast, submucosal myomas are found just beneath the endometrium, the inner lining of the uterus, while interstitial myomas are located within the muscular layer (myometrium) of the uterus. Intraligamentous myomas are a rarer type, located between the broad ligament folds, and are not primarily positioned on the outer surface of the uterus. Thus, subserosal myomas specifically are characterized by this outer placement, making them the correct answer.