German-french TV channel Arte TV made a short film (German, French) about the practice of Anasyrma, of lifting your skirt to publicly present your naked genitalia.
In the film, which starts with Gustave Courbet's painting The origin of the world, there are two more Flemish paintings from the 16th century:
Both paintings depict a scene from a story reported by Plutarch in his Moralia, where Persian women show their vulvae to fleeing Persian soldiers to scare them back onto the battlefield.
At the time when Cyrus induced the Persians to revolt from king Astyages and the Medes he was defeated in battle. As the Persians were fleeing to the city, with the enemy not far from forcing their way in along with the Persians, the women ran out to meet them before the city, and, lifting up their garments, said, "Whither are you rushing so fast, you biggest cowards in the whole world? Surely you cannot, in your flight, slink in here whence you came forth." The Persians, mortified at the sight and the words, chiding themselves for cowards, rallied and, engaging the enemy afresh, put them to rout.
Both paintings make the genitalia a central part of the painting, but depict a considerably larger scene. While the reproduction of Francken's painting is not large enough to say for sure, the one of van Veen clearly details the vulvae.
Looking through depictions of van Veens work, there is also his Amazones and Skythians with the same level of detail.