PRECAUTIONS: Before taking estradiol valerate, tell your doctor or pharmacist if you are allergic to it; or to other estrogen products or sesame oil; or if you have any other allergies. This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: undiagnosed abnormal vaginal bleeding, cancer (e.g., breast cancer - also see Uses section), blood clots, active/recent stroke or heart attack, liver disease. Before using this medication, tell your doctor or pharmacist your medical history, especially of: family medical history (especially breast lumps and cancer), asthma, diabetes, seizures, migraine headaches, heart disease (high blood pressure, heart attacks, congestive heart failure), kidney disease, low thyroid hormone (hypothyroidism), abnormal calcium level in the blood, depression, high blood pressure during pregnancy (toxemia), yellowing of eyes or skin (cholestatic jaundice) during pregnancy or with past estrogen use, womb problems (e.g., uterine fibroids endometriosis), cholesterol or lipid problems, gallbladder disease, excessive weight gain, certain blood disorder (porphyria). If you will be having surgery or will be confined to a chair or bed for a long period of time (e.g., a long plane flight), notify your doctor beforehand. Special precautions may need to be taken in these circumstances while you are taking this drug. This drug may make you dizzy; use caution engaging in activities requiring alertness such as driving or using machinery. Limit alcoholic beverages. This drug may cause a patchy darkening of the skin on the face (melasma). Sunlight may intensify this darkening and you may need to avoid prolonged sun exposure and sunlamps. Consult your doctor regarding use of sunscreens and protective clothing. Cigarette smoking can increase the chance of blood clots while taking this medication (especially in women over the age of 35). If this medication is used in children, their growth pattern should be monitored because it may stunt growth. This medication must not be used during pregnancy. If you become pregnant or think you may be pregnant, inform your doctor immediately. This medication may pass into breast milk and may have undesirable effects on a nursing infant. Therefore, breast-feeding while using this medication is not recommended.