The Pearl Index is the standard measure of contraceptive effectiveness. It is defined as the number of contraceptive failures per:
- A 100 couples per year
- B 100 woman-years of exposure ✓
- C 1000 woman-months of use
- D 1000 cycles of use
Correct answer: B. 100 woman-years of exposure
Explanation
The Pearl Index is defined as the number of unintended pregnancies per 100 woman-years of contraceptive use. It is calculated as: (Number of failures / Total months of exposure) × 1200. A lower Pearl Index indicates higher contraceptive effectiveness. Combined oral contraceptives have a Pearl Index of approximately 0.1–0.3 with perfect use and 7–9 with typical use.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.