Norethisterone enanthate

Norethisterone enanthate (NETE), also known as norethindrone enanthate, is a form of progestogen-only injectable birth control which is used to prevent pregnancy in women. It may be used following childbirth, miscarriage, or abortion. The failure rate per year in preventing pregnancy is 2 per 100 women. Each dose lasts two months with only up to two doses typically recommended. Norethisterone enanthate (NETE), also known as norethindrone enanthate, is a form of progestogen-only injectable birth control which is used to prevent pregnancy in women. It may be used following childbirth, miscarriage, or abortion. The failure rate per year in preventing pregnancy is 2 per 100 women. Each dose lasts two months with only up to two doses typically recommended. Side effects include breast pain, headaches, depression, irregular menstrual periods, and pain at the site of injection. Use in those with liver disease is not recommended as is use during pregnancy due to risk of birth defects. Use appears to be okay during breastfeeding. It does not protect against sexually transmitted infections. NETE is an ester and prodrug of norethisterone, through which it works. It works as a method of birth control by stopping ovulation. Norethisterone was patented in 1951 and came into medical use in 1957. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. The wholesale cost in the developing world is about US$1.04–7.99 per 200 mg vial. It has been approved by itself in more than 60 countries including the United Kingdom and some in Europe, Central America, and Africa, and in combination with estradiol valerate in at least 36 countries mainly in Latin America. It is not available in the United States. NETE is used on its own as a long-lasting progestogen-only injectable contraceptive in women. It is administered via intramuscular injection once every two months. Side effects of NETE may include breast pain, headaches, depression, irregular menstrual periods, and pain at the site of injection. It can cause birth defects in the fetus if used during pregnancy. NETE is a prodrug of norethisterone in the body. Upon reaching circulation, it is rapidly converted into norethisterone by esterases. Hence, as a prodrug of norethisterone, NETE has essentially the same effects as norethisterone, acting as a potent progestogen with additional weak androgenic and estrogenic activity (the latter via its metabolite ethinylestradiol). NETA has some progestogenic activity of its own, but it is unclear if NETE does similarly. NETE is of about 38% higher molecular weight than norethisterone due to the presence of its C17β enanthate ester. A single intramuscular injection of 50 to 200 mg NETE in oil solution has been found to have a duration of action of 11 to 52 days in terms of clinical biological effect in the uterus and on body temperature in women.