The 'Pearl Index' is used to measure contraceptive efficacy. A method with Pearl Index of 2.0 means:
- A 2% of users become pregnant in a lifetime of use
- B 2 pregnancies per 100 woman-years of exposure ✓
- C 2 out of every 100 tablets fail per cycle
- D 2% of women fail to comply with the method in one year
Correct answer: B. 2 pregnancies per 100 woman-years of exposure
Explanation
Pearl Index = (Number of accidental pregnancies × 1200) / (Total months of exposure) = pregnancies per 100 woman-years. A Pearl Index of 2.0 means 2 unintended pregnancies per 100 women using the method for one full year. Lower Pearl Index = higher efficacy. Combined OCP typical-use PI ≈ 7; perfect-use ≈ 0.3. Copper IUD ≈ 0.5; male condom typical use ≈ 13.
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.