Not that you know of

Recently, I’ve been in social situations with people I’m meeting for the first time. Twice, I’ve had the following exchange with men:

Male: “Do you have kids?”
Me: “No.”
Male, with smug smile: “Not that you know of!”

Pause. Take that in.

The human gestation period lasts 75% of a year. I’d know.

Both times I heard this, the man’s response to my answer was near-immediate as if I had teed up a familiar joke. The “punchline” came out like rapid-fire despite clear implausibility. A woman “not knowing” that she carried a fetus for 9 months and delivered a baby? Huh.

Here are two assumptions this statement makes when used between men:

• The male has had sex with women he is not connected with anymore. Not on social media, not via mutual friends (Is this a source of pride?).
• The woman or women he impregnated deliberately chose not to tell him (What does this imply?).

The comedic attempt masks dark undertones. Does this banter hide a real male worry?

Sincerely interested in hearing from men on why they use this line. In the meantime, think twice before joking with a woman about children she doesn’t know she birthed.