The 'Pearl Index' is used to evaluate contraceptive efficacy. A method with a Pearl Index of 2 means:

• A 2% of women using the method will become pregnant in their lifetime
• B The method has 98% efficacy in preventing pregnancy in a single act of intercourse
• C 2 out of 100 women fail to use the method correctly
• D 2 pregnancies occur per 100 woman-years of exposure to the contraceptive method ✓

Explanation

Pearl Index = (Number of unintended pregnancies × 1200) / (Total months of exposure). A Pearl Index of 2 means 2 pregnancies per 100 woman-years (equivalent to 100 women using the method for one year). Lower Pearl Index = higher efficacy. Combined OCP Pearl Index ~0.3 (perfect use); condom ~2–15 (typical use); copper IUD ~0.6–0.8. Pearl Index has limitations: assumes constant failure rate over time and does not account for differences in user populations.

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.