Medicine
Hormonal Feedback Loops in the Menstrual Cycle
Quick fact
The same hormone—estrogen—exerts negative feedback at moderate levels, but when it rises above a threshold for about 36 hours, it flips to positive feedback and triggers a massive LH surge that releases the egg.
Why this is interesting
Your body runs on a thermostat-like system—but one that suddenly flips into reverse just before ovulation. How does the menstrual cycle use feedback to control fertility?