It means they’re having bareback sex and the man orgasms while inside her.
It should not be tolerated at the workplace. I’m forced to listen to this rhetoric because my shift isn’t done yet, and I can’t leave without getting fired. I’m forced into a sexual discussion without consent, and it’s so graphically disgusting that I feel nauseous.
Your example was “we’re trying for a baby”, not literally your first sentence in your post.