The Pearl Index (PI) for combined oral contraceptive pills (COCPs) with PERFECT use is approximately:

• A 1.5–2.0 per 100 woman-years
• B 5–8 per 100 woman-years
• C 10–15 per 100 woman-years
• D 0.1–0.3 per 100 woman-years ✓

Explanation

With perfect (consistent, correct) use, COCPs have a Pearl Index of approximately 0.1–0.3 — fewer than 1 pregnancy per 100 women per year. With typical use the PI rises to approximately 7–9 due to missed pills and incorrect use. Pearl Index = (Number of pregnancies × 1200) / Total months of exposure; a lower PI denotes higher contraceptive efficacy. This distinction between perfect-use and typical-use failure rates is clinically important for counselling.

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.