The woman is a lieutenant. She and her male colleagues in the Infantry Officer Course completed an intensive combat exercise Wednesday at the Marines’ rugged training facility in Twentynine Palms, Calif., the final graded requirement of the 13-week program.

IOC, as it’s known among Marines, is considered some of the military’s toughest training. Typically, about 25 percent of students wash out.

The woman, whose name has not been disclosed, is the first female officer to complete the course out of three dozen to have tried. She is expected to lead an infantry platoon of about 40 Marines, a trailblazing role within an organization that has been criticized for its resistance to such change and for fostering a culture of misogyny. The service was engulfed in scandal earlier this year when more than 1,000 current Marines and veterans were investigated as part of an online network that shared, critiqued and in many cases ridiculed photographs of nude female colleagues.