He has a penis. He can make women pregnant, just like all the soldier ants. CANON SAYS SO.

http://www.mangahere.co/manga/hunter...1/c214/10.html

Who cares if he "looks like a woman"? Lots of men do. And they're still men. Who cares if he identifies as a man? Not you, apparently. Who cares if he "feels" like a woman? Uhhh...