Levonorgestrel and Ethinyl Estradiol, known as Alesse, is an effective birth control method. This is a combination oral contraceptive that prevents ovulation and changes the uterus so that eggs have extreme difficulty implanting. The drug is also marketed under a few different brands including: Aviane, Levlite, Levlen, Levota, Tri-leven, Triphasil, Trivora and Triphasil-28.This brand or other brandsLevonorgestrel and Ethinyl Estradiol are the synthetic hormones used in Alesse and the other brands. Levonorgestrel is the estrogen and Ethinyl Estradiol is the progestin. This doesn’t mean that they are identical. The difference is mainly due to the dosages and whether or not the birth control pill is triphasic, biphasic or uniphasic. If you are to switch between brands thinking they are the same you might be surprised by the way the new brand interacts with your body. A doctor’s consultation would be best.What are mutlphasic oral contraceptives?Combination birth control pills contain both estrogen and progestin and they are mutiphasic or singlephasic. A singlephasic pill will have the same dosage throughout the entire 21 day pack pills. The other 7 pills (of 28) have no hormones and are there to maintain the habit of taking them regularly. In multiphasic pills the dosage of progestin changes during the 21 days. Estrogen levels usually remain the same. In biphasic pills there are two different levels of progestin and in triphasic there are 3. The levels of hormones and the way they are delivered change from brand to brand even though the actual hormones are the same.Usage PrecautionsWomen who are pregnant should not take any hormonal oral contraceptives as well ass women who have just given birth. Anyone with heart problems, blood clots or circulatory problems related to diabetes, uterine or breast cancer (cancers related to hormones), high blood pressure, abnormal menstrual bleeding and liver problems is also advised to avoid Alesse. Also, smokers especially if they are over the age of 35 should avoid hormonal contraceptives.When starting out using any birth control pill, it’s a good idea to use another form of birth control such as condoms or a spermicidal cream as a backup. Your doctor can give specific information as to how long a period of time to use a back up plan before relying on the contraceptive pill alone.