This is an interesting question about a very interesting story. "Bloodchild" is the story of humans who have been enslaved by aliens far from Earth. The only hint that a reader might get that the author, Olivia Butler, is African American is the fact of people's enslavement in a land far from their homeland. Like slaveholders, the aliens, or Tlic, are both benevolent and wicked. Humans and Tlic can play together and be friends as children, but as adults they can never be equal; the Tlic own the humans and do whatever they want with them, even separating families by giving children to other Tlic to own.
Are there any hints that the author is a woman? Maybe the fact that the story is about pregnancy and childbirth is a small clue, but I really don't see anything that would identify the author as male or female.
I hope this helps you!