Obstetrician-gynecologists frequently are consulted either before the initiation of cancer treatment to request menstrual suppression or during an episode of severe heavy bleeding to stop bleeding emergently. Adolescents presenting emergently with severe uterine bleeding usually require only medical management; surgical management rarely is required. Surgical management should be considered for patients who are not clinically stable, or for those whose conditions are not suitable for medical management or have failed to respond appropriately to medical management. When used continuously, combined hormonal contraceptives are effective for producing amenorrhea, although complete amenorrhea cannot be guaranteed. The risk of venous thromboembolism in patients with cancer is compounded by multiple factors, including presence of metastatic or fast-growing, biologically aggressive cancers; hematologic cancers; treatment-related factors such as surgery or central venous catheters; and the number and type of comorbid conditions. Although as a group, patients undergoing cancer treatment are at elevated risk of venous thromboembolism compared with the general population, this risk may be extremely elevated for certain patients and existing guidance on risk stratification should be consulted. The decision to use estrogen in patients with cancer should be tailored to the individual patient after collaborative consideration of the risk-benefit ratio with the patient and the health care team; the patient should be closely monitored for known adverse effects such as liver toxicity and venous thromboembolism.