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The US Food and Drug Administration (FDA) has not approved any injectable contraceptives, but, in December 1990, it approved Norplant, an implantable contraceptive. Family planning providers insert 6 capsules, each with 36 mg levonorgestrel, in a fan shape under the dermis of the upper arm. Norplant protects against pregnancy for at least 5 years . Fecundity returns within 2 weeks after capsules' removal. The steady low levels of levonorgestrel keep down both luteinizing hormone and follicle stimulating hormone levels. It suppresses ovulation and thickens the cervical mucus. Contraindications of Norplant are active thromboembolism, undiagnosed genital bleeding, acute liver disease, liver tumors, and breast cancer. Phenytoin and other drugs which speed up liver metabolism reduce Norplant's efficacy. The leading side effect of Norplant is irregular bleeding patterns. Some less common side effects include headaches, nervousness, dizziness, and acne. First year continuation rates range from 76 to 99% and 25 to 78% for 5 years of use. More than 85% of Norplant users are satisfied. Both continuation and satisfaction are associated with patient counseling. Research and development of biodegradable and other nonbiodegradable implants is ongoing. The most common injectable contraceptive in the world is Depo-Provera. 150 mg of Depo-Provera every 3 months suppresses ovulation, deteriorates the endometrium, thickens cervical mucus, and reduces motility of the tubes, thereby providing adequate protection against pregnancy. Some research shows Depo-Provera use significantly increases the low-density lipoprotein to high-density lipoprotein ratio, thereby increasing the risk for atherogenesis. Effectiveness rates match those of Norplant. Norethindrone enanthate was the first injectable contraceptive. Even though 40 countries approve it, the US does not. Animal studies of injectable microspheres or microcapsules with either progestogen or progestogen and estrogen are in progress.
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PMID:Injectable and implantable contraceptives. 138 11

The Norplant System consists of 6 capsules each containing 36 mg of crystal line levonorgestrel (LNG), for a total dose of 216 mg LNG. The capsules are inserted subdermally in the mid-upper arm, and LNG diffuses continuously through the capsule walls for 5 years. In the United States the Norplant System was approved in December 1990. The initial rate of hormone delivery is about 85 mcg/day, then decreases over the next 9 months to 5 mcg/day, and over the ensuing 9 months to 35 mcg/day. Thereafter, the diffusion rate levels off for the next 3.5 years, averaging around 30-35 mcg/day. Removal results in a drop in the plasma concentration of levonorgestrel to below contraceptive levels within 24 hours and below the detectable limit of .1 pg/ml at 96 hours. Preliminarily data from 402 users over 5 years show improvements of Norplant produced better efficacy in all weight classes and a lowered cumulative rate of 1.1 pregnancies of 100 users. The pregnancy rate for the first year of use is 02., better than for oral contraceptives. Side effects include headache, nervousness, nausea, dizziness, dermatitis, acne, change of appetite, breast tenderness, minimal weight gain, some change in hair distribution, and adnexal enlargement. Adverse reactions include breast discharge, possible cervicitis, musculoskeletal pain, abdominal discomfort, leukorrhea, and vaginitis. More than the usual number of bleeding days occurred in slightly more than one fourth of the patients, prolonged bleeding in 27.6% spotting in 17.1% and amenorrhea in 9.4% of patients. Hyperlipidemic users should be observed for possible low-density lipoprotein elevations. The cumulative discontinuation rate for pregnancy was 3.9 per 100 users; for bleeding irregularities the rate was 25.1 per 100 users, and for other medical results it was about 22.4 per 100 users. Personal reasons for discontinuation accounted for 38.7 per 100 users, equivalent to a cumulative continuation rate of about 30 per 100 users over the 5-year duration.
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PMID:The NORPLANT system of contraception. 168 4

The mean of the Norplant usage period of 338 acceptors was 44.4 months. Most users had poor education and low incomes; the lower their socioeconomic status, the longer they used the Norplant implant. Return to fertility 3 months after removal was 38.46%; after 6 months, 71.43%; after 9 months, 74.46%; and after 12 months, 75%. The continuation rate at year one was 82.84%; year 2, 74.85%; year 3, 68.34%; year 4, 64.79%; while year 5 was 8.58%. The mean removal time was 21 minutes. There was a very significant difference between trained and untrained removers in the duration of removal. The average number of capsules removed was 5.64. There was no significant difference between trained and untrained removers in successful capsule removal. Reasons for removal were expired date and non-medical complaints such as changing to other contraceptives and the wish to become pregnant; medical complaints were dizziness, vertigo, spotting and amenorrhea. Removal was prompted by acne, metrorrhagia, two or more medical complaints, menorrhagia, physical pain, tenderness at insertion site and spotting. There were no pregnancies found among acceptors. However, 5.92% of the acceptors were pregnant at the time of insertion because of misdiagnosis. It can be concluded that Norplant is effective, safe and acceptable but removal needs trained persons.
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PMID:The Norplant removal training and service at Dr Kariadi Hospital, Semarang, Indonesia. 177 63

Between April and October 1991 in Baltimore, Maryland, family planning providers tried to follow 246 13-42 year old women at a clinic at the Francis Scott Key (FSK) Medical Center for 3 months who accepted the levonorgestrel-releasing implant Norplant to evaluate its acceptability and effectiveness among a high-risk population. 56% of the women were Black and 41% White. 69% were single. Most were interval gynecologic patients (109), but many were postabortion patients (97). The providers could only follow 108 women. Reasons for unscheduled visits were insertion site tenderness, amenorrhea, and removal. At 1 month, 70 % had at least 1 side effect. 48% had irregular bleeding 1-2 months after insertion. Other side effects included headache (49%), acne (24%), weight gain (22%), increased appetite (19%), and dizziness (18.5%). The 24-hour telephone hotline had only received 38 problem calls, all of which were from FSK Norplant patients. More than 50% of the calls were about menstruation concerns. Reasons for removal included pressure to receive Norplant, increased acne, headaches and prolonged bleeding, and postinsertion site problems. 1 woman became pregnant, but it occurred before insertion. She underwent an abortion and continued to use Norplant. 78% of the women considered Norplant to be excellent and 14% considered it to be good. 95% would recommend it to others. 69% reported convenience to be the best thing about Norplant and 22% said it was pregnancy prevention. Worst things were irregular bleeding (26%) and progestin-related side effects (e.g., headaches and weight gain) (19%). 35% did not consider anything to be bad about Norplant. 64% had at least some apprehension before insertion, the major reasons being fear of needles (48%) and of pain (37%). Prior to insertion, just 37% were worried about potential side effects. The providers thought that the routine follow-up visit at 1 month was not cost-effective and provided no specific clinical benefit. They advocated adequate counseling about side effects to take the place of the follow-up visit.
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PMID:Preliminary experience with Norplant in an inner city population. 844 19

This paper describes the first two years of Norplant use among 1560 acceptors in two rural counties of Hebei province and two rural counties of Shandong province, China. No pregnancies were reported during Norplant use, with an overall continuation rate of 88.4% after two years. Many women did, however, report side effects, including menstrual problems, headache, dizziness, and nausea among 46.7%, 6.7%, 6.3%, and 3.3% of women, respectively. Menstrual cycle disruption accounted for 77% of all Norplant removals. The majority of removals due to menstrual problems occurred in the second year of use, while most of the removals due to other causes occurred during the first year of use. Clinical performance among the four counties was diverse, with two-year continuation rates of 73.9-95.3%. Factors which may contribute to the diversity among study sites and the overall high continuation rate are discussed in the context of Chinese family planning.
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PMID:Introduction of Norplant implants in four counties of rural China: a two-year evaluation. 874 98

The Norplant system is a long-acting hormonal contraceptive method for women which offers high efficacy. The active principal is levonorgestrel, a progestin widely used in oral contraceptives. The Norplant system is in use in various countries including the US, the Dominican Republic, Colombia, Brazil, Chile, Sweden, and Denmark. Norplant consists of silastic capsules containing levonorgestrel which are inserted subdermally in the arm. The progestin is released in constant form from the moment of implantation. 50 mcg are released daily during the first year and approximately 30 mcg are released in subsequent years. Norplant is effective for at least 5 years if a set of 6 capsules is used. Norplant II, consisting of 2 capsules used for 3 years, has come into use more recently. The cumulative pregnancy rate after 5 years of use by 992 women was 2.7/100 continuous users. The annual pregnancy rate was generally less than .5%. No other reversible method has demonstrated the same level of effectiveness during such prolonged periods of use. The mechanism of action is based on inhibition of ovulation in about 50% of cycles, thickening of cervical mucus, and endometrial suppression. Norplant users may present some adverse effects such as menstrual irregularities, amenorrhea, nausea, dizziness, or headaches, but these symptoms are less frequent than with other hormonal methods. Menstrual irregularity is the most frequent secondary effect and the principal cause of termination of use. The secondary effects are generally acceptable. Follow-up during the period of effectiveness of the implants is simple and infrequent. Norplant is an excellent contraceptive choice for women who do not desire pregnancy but do not wish to use a definitive contraceptive method. Once the implant is removed, fertility rapidly is restored.
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PMID:[Norplant: a new alternative in family planning]. 1217 15

71 Egyptian women using Norplant contraceptive implants for 1 year were followed with laboratory testing of carbohydrate, lipid and protein metabolism, liver and kidney function tests, serum iron and iron binding capacity and pituitary response to GnRH. The subjects were normal, healthy fertile, non-pregnant, non-lactating women who had not used hormone for 6 months. There were no pregnancies. Most women complained of altered menstrual patterns. Some reported headache, dizziness, increased vaginal discharge, nausea, and pain at the insertion site. There was no significant change in fasting or post-prandial glucose, or kidney function. Cholesterol decreased significantly at 3 months, triglycerides fell at 3 and 12 months, and HDL rose significantly at 3 and 12 months. SGPT fell significantly at 3 and 12 months. Total protein and albumin was significantly lower at 12 months. Serum iron and total iron binding capacity were significantly elevated at 3 and 12 months. Secretion of LH and FSH fluctuated around normal limits. The lipoprotein findings are discrepant from those reported from other developing countries in Norplant trials.
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PMID:Clinical chemistry and pituitary response changes in Egyptian acceptors of L. Norgestrel six rods implants during the first year of use. 1228 53

A clinical trial was carried out on the levonorgestrel-containing subdermal contraceptive implant to evaluate its efficacy and acceptability among Malaysian women. The study recruited 121 women in and around the Kuala Lumpur Federal Territory over a 13-month period (March 1986-March 19870 and followed regularly for 2 years at intervals of 3, 6, 12, and 24 months. The acceptors consisted of 53.7% Malays, 24.8% Indians, and 21.5% Chinese. 81% of the selected females were between 20-34 years in age (mean=30). The average parity was 3.9 children; 81.8% reported that they did not want to have a child in the he next 3 years. In the last 6 months, 45.5% of the study group had used the oral contraceptive pills, 15.7% had used the intrauterine contraceptive device, and 17.4% had not employed any method. The results showed that the subdermal implant Norplant (R) is effective and safe. The gross cumulative continuation rate was 93.8 at 6 months, 88.2 at 12 months, and 72.2 at 24 months. Within the 24 month period, 26 terminations occurred as a result of pregnancy (n=1), menstrual problems (n=9), medical reasons (n=12), and personal reasons (n=4). the gross cumulative termination rate/100 women for pregnancy was 0 at 12 months and 1.7 at 24 months. Major side effects include menstrual problems, weight gain, dizziness, and headache. After 1 year, 13.3% of the cases (n=2) had the implant removed. The acceptability of the method among our women in 4 clinics around Kuala Lumpur and other Norplant (R) studies in other countries is comparable to the intrauterine devices among Malaysian women; the termination rate for accidental pregnancy is lower than that of IUD. The device is easy to administer in a small clinical set-up though it requires personnel specially trained in the surgical techniques; 86.0% of the acceptors reported complication-free insertion. This may be a method to be introduced to our National Family Planning Program in our efforts to offer a wider range of safe and effective methods of family planning. (author's modified).
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PMID:A study of the acceptability and effectiveness of Norplant (R) contraceptive implants in Kuala Lumpur, Malaysia. 1231 41

"New Era for Injectables," a report published in the most recent issue of the Johns Hopkins University School of Hygiene and Public Health's Population Reports, notes that injectable contraceptives are among the most effective family planning methods. Most clinical trials report less than one pregnancy per 100 women during the first year of use, making injectables as effective as Norplant implants, the best copper IUDs, and voluntary sterilization. Injectables also protect women against ectopic pregnancy, help to prevent endometrial and possibly ovarian cancer, and may help women with anemia and sickle-cell disease. The major side effect of injectable use is changes in menstrual bleeding. Some women also experience weight gain, and a few report headaches, dizziness, abdominal discomfort, acne, and moodiness. The most widely-used injectable is the progestin-only DMPA (depot medroxyprogesterone acetate), known under the brand name Depo-Provera and manufactured by the Upjohn Company. Women receive an injection every 3 months. Another progestin-only injectable, NET EN (norethindrone enanthate), is taken every 2 months. Cyclofem and Mesigyna, two new monthly injectables which combine estrogen and progestin, are currently being introduced in a number of countries. Worldwide, 1.5% of all married women of reproductive age who use some form of family planning use injectables. The highest level of use among such women is in Indonesia and Thailand where 15% and 12%, respectively, use injectables. Donor agencies have been responding to increasing numbers of orders for injectables from family planning programs in developing countries, while the UN Population Fund, the largest supplier, shipped 12 million doses of injectables in 1992 and 20 million in 1994. The 1992 US Food and Drug Administration approval of DMPA has made it possible for the US Agency of International Development to respond to requests for it.
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PMID:Millions of couples to have choice of injectable contraceptive. 1234 10

Levonorgestrel-releasing implants are long acting contraceptives, approved for 5 years of continuous use. Two marketed systems, the six capsule Norplant use of tradenames is for product identification purposes only and does not imply endorsement. and the two rod Jadelle, have essentially equal rates of drug release, pregnancy and adverse events over 5 years of use. Randomised clinical trials and controlled cohort observations indicate that for the first 3 years, when pregnancy rates are at or almost zero, no other contraceptive system is more effective, although etonogestrel implants provide equal effectiveness. Annual pregnancy rates rise in the fifth year of continuous use but remain below 1 per 100 women. Annual pregnancy rates of Norplant users remain below 1 per 100 throughout 7 years of continuous use. Levonorgestrel implants provide low progestogen doses; 40-50 microg/day at 1 year of use, decreasing to 25-30 microg/day in the fifth year. Serum levels of levonorgestrel at 5 years are 60-65% of those levels measured at 1 month of use. Adverse effects with levonorgestrel implants are similar to those observed with progestogen only and combined oral contraceptives. Risks of ectopic pregnancy, other pregnancy complications and pelvic inflammatory disease are reduced in comparison with those of women using copper or non-medicated intrauterine devices. Risks of developing gallbladder disease and hypertension or borderline hypertension, although small, are about 1.5 and 1.8 times greater, respectively, in women using levonorgestrel implants than in women not using hormonal contraception. Other serious diseases have not been found to occur significantly more frequently in levonorgestrel implant users than in women not using hormonal contraception. The great majority of levonorgestrel implant users experience menstrual problems, but serious bleeding problems are not more frequent than in controls. Other health problems reported more frequently by levonogestrel implant users than by women not using hormonal contraception in a study of 16000 women included skin conditions, headache, upper limb neuropathies, dizziness, nervousness, malaise, minor visual disturbances, respiratory conditions, arthropathies, weight change, anxiety and non-clinical depression. Clinical depression is not more frequent in women using implants compared with those not using hormonal contraception (i.e. using intrauterine devices, sterilisation). Removal problems occur less frequently with Jadelle than with Norplant. The mean removal time for Jadelle is half that of Norplant. Levonorgestrel implants in nationally representative scientific samples, in randomised trials, and in controlled cohort studies have continuation rates as high as or higher than any other reversible contraceptive over a duration of 5 years. This would imply that the satisfaction women derive from the contraceptive effectiveness of levonorgestrel implants greatly outweighs the dissatisfaction that may accompany menstrual disturbances and other adverse effects associated with implants.
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PMID:Risks and benefits, advantages and disadvantages of levonorgestrel-releasing contraceptive implants. 1265 Jun 33


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