Hemoptysis after physical activity is a well-known phenomenon. Hemoptysis following sexual intercourse is rarely reported. We describe three patients with hemoptysis occurring only after sexual activity and not following other types of physical effort. The underlying causes were congestive heart failure, uncontrolled hypertension and Takayasu arteritis. The literature is reviewed. We conclude that hemoptysis can present rarely following sexual activity and is usually associated with cardiovascular decompensation. It is always necessary to search for other underlying diseases. We suggest that patients with unexplained hemoptysis should be specifically asked about postcoital hemoptysis should be included in the differential diagnosis of every patient with unexplained hemoptysis.