Levonorgestrel is a hormonal medication which is used in a number of birth control methods. It is combined with an estrogen to make combination birth control pills. As an emergency birth control, sold under the brand name Plan B among others, it is useful within 72 hours of unprotected sex. The more time that has passed since sex, the less effective the medication becomes, and it does not work after pregnancy (implantation) has occurred. Levonorgestrel works by preventing ovulation or fertilization from occurring. It decreases the chances of pregnancy by 57 to 93%. In an intrauterine device (IUD), such as Mirena among others, it is effective for the long-term prevention of pregnancy. A levonorgestrel-releasing implant is also available in some countries.Common side effects include nausea, breast tenderness, headaches, and increased, decreased, or irregular menstrual bleeding. When used as an emergency contraceptive, if pregnancy occurs, there is no evidence that its use harms the fetus. It is safe to use during breastfeeding. Birth control that contains levonorgestrel will not change the risk of sexually transmitted infections. It is a progestin and has effects similar to those of the hormone progesterone. It works primarily by preventing ovulation and closing off the cervix to prevent the passage of sperm.Levonorgestrel was patented in 1960 and introduced for medical use together with ethinylestradiol in 1970. It is on the World Health Organizations List of Essential Medicines. It is available as a generic medication. In the United States, levonorgestrel-containing emergency contraceptives are available over the counter (OTC) for all ages.
Diagnosis
In the diagnosis of pulmonary insufficiency both echocardiograms and ECG is used to ascertain if the individual has this condition, as well as, the use of a chest x-ray to expose enlargement of the right atrium or ventricle. Treatment
In treating pulmonary insufficiency, it should be determined if pulmonary hypertension is causing the problem to therefore begin the most appropriate therapy as soon as possible (primary pulmonary hypertension or secondary pulmonary hypertension due to thromboembolism). Furthermore, pulmonary insufficiency is generally treated by addressing the underlying condition, in certain cases, the pulmonary valve may be surgically replaced. See also
Pulmonary valve stenosis

References
Further reading
Lake, Carol L.; Booker, Peter D. (2005-01-01). Pediatric Cardiac Anesthesia. Lippincott Williams & Wilkins. ISBN 9780781751759. Bruce, Charles J.; Connolly, Heidi M. (2009-05-26). "Right-Sided Valve Disease Deserves a Little More Respect". Circulation. 119 (20): 2726–2734. doi:10.1161/CIRCULATIONAHA.108.776021. ISSN 0009-7322. PMID 19470901. M.D, Steven Lehrer (2011-12-27). Understanding Pediatric Heart Sounds. Steven Lehrer. ISBN 9781468138030. External links
"Problem: Pulmonary Valve Regurgitation". www.heart.org. Retrieved 2015-08-29.