Hormones do the damnedest things

On Saturday night, Fiona and I had just gotten home from a dinner party. It was a bit late and we were walking into the house when Fiona tripped over the front stair and careened face first into a stone wall. She bruised both of her knees, gave herself a cut above the right eye and broke her glasses clear in two. It was a bit of a scary moment, but she had the woman's instinct to protect the baby by smashing her face into the wall rather than land on her tummy. Is there any other circumstance in which crashing face first into a stone wall is considered a protective instinct? I'll report back if I can think of any.