A bar, one Thursday night, after work. I'm sharing a bottle of wine with a group of colleagues when I fall into conversation with Mark, a friend of a friend. I mention in passing that my workload has increased because a member of my team is on maternity leave. "That's OK," he says. "Women hold the fort for each other because you'll be hoping someone will do it for you."

I bristle. "It isn't really OK because, well, I don't want kids," I say. He looks at me curiously. I take a defensive sip of wine.

"You can't have them?"

I sigh. "No. I don't want to have them."

"Why do you think you don't want to have them?"

"I don't think. I know."

"No, you don't," he scolds. "How could you?" Things spiral downward from there.