Sayana Press 104mg Injection is used for contraception (preventing pregnancy). It helps to prevent development and release of egg from the ovaries during menstrual cycle thus prevents pregnancy. Sayana Press 104mg Injection is administered only by or under the supervision of doctor. It should be taken as your doctor advice. Your doctor will decide how much you need to take and for how much time. You should take this injection for as long as it is prescribed for you. The most common side effects of this medicine include headache, dizziness, abdominal pain, nervousness, weight gain, and breast tenderness. If any of these bothers you, let your doctor know. There may be ways of reducing or preventing them. It may also cause irregular menstrual cycle, spotting or your menstrual bleeds to stop altogether. Inform your doctor if you get heavy or prolonged bleeding. Before taking this medicine, you must let your doctor know if you ever had any problems like history of blood clots, stroke, heart attack, liver, or bleeding problems. Your doctor should also know about all other medicines you are taking as many of these may make this medicine less effective or change the way it works. You must not take it if you are pregnant.