Both female and male hyenas have nearly identical-looking genitalia, but only because females disguise their sex organs as penises until they find a suitable mate. This disguise is known as a pseudo-penis; in fact, her fused labia look just like a scrotum to complete the look.
Female hyenas can invert their pseudo-penises at any time to let males take care of business, but this decision is made entirely at her discretion. Conversely, she can reject any male by refusing to invert her pseudo-penis when he approaches her
Although convenient for mate selection, the pseudo-penis can make giving birth more challenging. Many times, the mother or cub doesn't survive if it's the mother's first attempt at birth. The narrow passage sometimes asphyxiates the cub, or related injuries spell out the end for the mother before she finishes.
Given all the commotion, why don't female hyenas have vaginas like countless other mammals? The answer comes down to evolution. Female hyenas dominate their male counterparts and become aggressive toward other females. This development makes distinguishment more difficult and reduces conflict in the process, which seems advantageous in the wild.