Prostagen Vaginal gel is used to restore menstrual cycles in women whose periods have stopped. It is a natural female hormone important for regulating ovulation (release of an egg from a woman's ovary) and menstruation. It is also used in the treatment of infertility to help you get pregnant. You should use Prostagen Vaginal gel as your doctor has advised. Do not use more or less than you have been advised and do not use it for longer than recommended. You may be asked to continue this medicine for a period after it is confirmed that you are pregnant. The most common side effects include headache, sleepiness, abdominal pain, breast tenderness, and itching or burning sensation. Very occasionally people get a severe allergic reaction which needs urgent medical attention. It may not suit everybody, and you should tell your doctor if you have or have had, breast cancer, unusual bleeding in the vagina, or liver disease. You may be monitored more carefully if you have liver, kidney, or heart problems or have diabetes or asthma. Let your doctor know your medical history to be safe. Also, let your doctor know about all other medicines which may affect, or be affected by, this medicine. You will probably have several tests both before and during treatment to check your womb. It is advisable not to use any other vaginal products or cream while using this medicine.