Table 1

 World Health Organization (WHO) classification of risk from contraceptive use and pregnancy in cardiovascular disease

WHO classRisk for contraceptive method by cardiac conditionPregnancy risk by cardiac condition
WHO 1 Always useableRisk no higher than general populationRisk no higher than general population
WHO 2 Broadly useableSmall increased risk; advantages of method generally outweigh risksSmall increased risk of maternal mortality and morbidity
WHO 3 Caution in useRisks usually outweigh advantages of method. Other methods preferable. Exceptions if:Significant increased risk of maternal mortality and morbidity. Expert cardiac and obstetric pre-pregnancy, antenatal and postnatal care required
1. Patient accepts risks and rejects alternatives
2. Risk of pregnancy very high and other methods less effective
WHO 4 Do not useMethod contraindicated: represents unacceptable health riskPregnancy contraindicated: very high risk of maternal mortality or severe morbidity. Termination should be discussed. If pregnancy continues, care as for class 3