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What is Pearl index is used to calculate: March, September 2009 and explain in detail?
Ans. A: Accidental Pregnancies Methods of contraception are compared by the Pearl index. A high Pearl index stands for a high chance of unintentionally getting pregnant; a low value for a low chance. The Pearl index will be determined by the number of unintentional pregnancies related to 100 women years. E.g. 100 women can contracept for 1 year each with the method that is going to be examined. If three pregnancies occur during this period in this group, the Pearl index will be 3.0.