Gynaecology & Obstetrics Mechanism of action of combination OCPs in treatment of AUB – E A Diminshed prostaglandin synthesis. B Decreased endometrial fibrinolysis. C Endometrial atrophy. D All of the above. 💡 Explanation Mechanism of action of combination OCPs in treatment of AUB - E ✓ Correct Answer: D. All of the above.