Injectable contraceptives

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Injectable contraceptives

  1. 1. INJECTABLE CONTRACEPTIVES www.freelivedoctor.com
  2. 2. Introduction <ul><li>Injectable contraceptives contain hormonal drugs that provide women with safe , highly effective , and reversible contraceptive protection . </li></ul>www.freelivedoctor.com
  3. 3. Two types of injectable contraceptives : <ul><li>(1) Progestogen-only formulations that contain a progestogen hormone and are effective for 2 or 3 months; and, </li></ul><ul><li>(2) Combined formulations that contain both a progestogen and an estrogen and are effective for 1 month </li></ul>www.freelivedoctor.com
  4. 4. Progestogen -only formulations <ul><li>Consist of DMPA (depot med-roxyprogesterone acetate) and NET-EN (norethisterone enanthate). </li></ul><ul><li>DMPA is the injectable formulation most widely used worldwide . </li></ul><ul><li>DMPA is injected every 3 months. </li></ul><ul><li>NET-EN is injected every 2 months. </li></ul>www.freelivedoctor.com
  5. 5. Combined formulations <ul><ul><li>The most extensively studied formulations are known by their brand names, Mesigyna ; </li></ul></ul><ul><ul><li>Monthly injectable. </li></ul></ul><ul><ul><li>Mesigyna contains the same progestogen as NET-EN .& contains an added estrogen. </li></ul></ul>www.freelivedoctor.com
  6. 6. Combined formulations <ul><li>Administered by a deep intramuscular injection into the muscle of the arm or buttock and are effective immediately , provided they are taken at specified times </li></ul>www.freelivedoctor.com
  7. 7. <ul><li>All injectable contraceptives are slowly absorbed into the bloodstream from the injection site, with the body maintaining a sufficient level of hormone to provide contraception for 1 to 3 months, depending on the type of injectable used </li></ul>www.freelivedoctor.com
  8. 8. www.freelivedoctor.com Common trade names Duration of effect Active ingredients Name Depo-Provera, Depo-Clinovir, others 90 days 150 mg medroxyprogesterone acetate in an aqueous microcrystalline suspension DMPA (progestogen-only) Noristerat, Norigest, Doryxas, and others 60 days 200 mg norethisterone enanthate in an oily preparation NET-EN (progestogen-only ) Mesigyna, Norigynon 30 days 50 mg norethisterone enanthate and 5 mg estradiol valerate Mesigyna (combined)
  9. 9. PROGESTOGEN ONLY INJECTABLES www.freelivedoctor.com
  10. 10. Mode of Action <ul><li>The immediate action of progestagen-only injectables (POIs) is to thicken cervical mucus , which then presents an obstacle to sperm penetration. </li></ul><ul><li>Also, ovulation is impaired . </li></ul><ul><li>There are additional changes in the endometrium that make it unfavourable to implantation; however, the first two effects make fertilisation highly unlikely. </li></ul>www.freelivedoctor.com
  11. 11. Efficacy <ul><li>The reported failure rates of POIs are low, and come within the narrow range of </li></ul><ul><li>0.1% to 0.6%. </li></ul>www.freelivedoctor.com
  12. 12. Beneficial Effects <ul><li>Prevention of pregnancy </li></ul><ul><li>A single injection of a POI can provide highly effective protection against pregnancy for two or more months, depending on the formulation. </li></ul><ul><li>Delivery is simple , independent of coitus, and ensures periodic contact with medical or other trained health personnel. </li></ul><ul><li>This is a suitable method for women in whom oestrogens present health risks – eg, those with a history of thromboembolic disorders - and those who have had side effects with the use of oestrogens. </li></ul>www.freelivedoctor.com
  13. 13. Non-contraceptive health benefits <ul><li>Clear benefits </li></ul><ul><li>Sickle cell disease: In a two-year trial, women with sickle cell disease using DMPA had significantly fewer crises than women given a placebo. </li></ul><ul><li>Anaemia: POIs can increase haemoglobin concentration, mainly by reducing menstrual blood loss. </li></ul>www.freelivedoctor.com
  14. 14. Non-contraceptive health benefits <ul><li>Possible benefits </li></ul><ul><li>1. Endometrial cancer: </li></ul><ul><li>In a World Health Organization (WHO) study, women who had ever used DMPA had one-fifth the risk of developing endometrial malignancy observed in women who had not used DMPA. </li></ul><ul><li>The results, although not statistically significant, support the hypothesis that use of DMPA might protect against this form of cancer. </li></ul><ul><li>2. Other: </li></ul><ul><li>The use of POIs possibly protects against pelvic inflammatory disease (PID), seizures in women with epilepsy, uterine myoma, and endometriosis. </li></ul>www.freelivedoctor.com
  15. 15. PROGESTOGEN ONLY INJECTABLES <ul><li>SIDE EFFECTS </li></ul>www.freelivedoctor.com
  16. 16. Menstrual irregularities <ul><li>DMPA and NET-EN are associated with disruptions of the menstrual cycle including amenorrhoea, prolonged menses, spotting between periods, and heavy bleeding. </li></ul><ul><li>Less than one-third of women receiving DMPA report having normal menstrual cycles during the first year of use. </li></ul>www.freelivedoctor.com
  17. 17. Menstrual irregularities <ul><li>Amenorrhoea is the most common side-effect and its occurrence increases with duration of use from about 50 % of DMPA users by the end of one year to 80% by the end of 5 years. </li></ul><ul><li>Women using NET-EN are less likely to experience amenorrhoea. </li></ul>www.freelivedoctor.com
  18. 18. Menstrual irregularities <ul><li>Heavy bleeding is uncommon (occurs in 1-2% of users), and prolonged bleeding is seldom heavy enough to be a threat to health. </li></ul><ul><li>Any woman who reports prolonged or heavy bleeding may need to be evaluated for anemia . </li></ul><ul><li>Anaemia treatments include nutritional advice & an appropriate dosage of oral iron tablets . </li></ul>www.freelivedoctor.com
  19. 19. Menstrual irregularities <ul><li>Treatments for heavy bleeding include non-aspirin anti-inflammatory drugs such as ibuprofen, short-term use of combined oral contraceptives or estrogen, or early administration of the next injection (not sooner than 4 weeks after the previous injection). </li></ul><ul><li>If these measures are not effective or the woman’s health is threatened, POIs should be discontinued. </li></ul>www.freelivedoctor.com
  20. 20. Other Side-Effects <ul><li>After menstrual changes, weight gain, headache, and dizziness are the next most common side-effects reported. </li></ul><ul><li>Most users of POIs put on weight and this is a common reason for discontinuation. </li></ul><ul><li>The average DMPA user gains 1.5–2.0 kg in the first year and some users continue to gain weight thereafter at about the same rate. </li></ul><ul><li>In clinical trials, between 3% and 19% of users of injectables have reported headache or dizziness . Few women discontinue for these reasons. </li></ul>www.freelivedoctor.com
  21. 21. Possible Carcinogenicity <ul><li>Clinical studies have found no association between DMPA use and cervical, ovarian, or liver cancers , </li></ul><ul><li>And have confirmed a substantial protective effect against endometrial cancer. </li></ul><ul><li>Studies have found no overall increase in risk of breast cancer. </li></ul><ul><li>Although some studies have indicated a small increased risk of breast cancer in some younger women following initial exposure, the studies show no trend toward increased risk among more long-term users. </li></ul>www.freelivedoctor.com
  22. 22. Bone density <ul><li>Findings to date suggest a relatively small and reversible effect , with no serious health risk for women of any age . </li></ul><ul><li>At present, medical experts recommend no restriction on use of injectables by adolescents over age 16. </li></ul><ul><li>Changes in calcium uptake by bone and decreases in urinary calcium excretion have been documented and there is a suggestion of a relation between long term use of DMPA and low bone mass. </li></ul>www.freelivedoctor.com
  23. 23. Effect on fetal exposure <ul><li>There are no known adverse effects of fetal exposure to injectables. </li></ul><ul><li>Studies of teenage children who were exposed to DMPA in utero show no significant differences in health, growth, or sexual development compared to other children. </li></ul><ul><li>Progestogen-only injectables can be used by breastfeeding women at 6 weeks postpartum without adverse effects on nursing infants. </li></ul>www.freelivedoctor.com
  24. 24. Effect on Metabolism <ul><li>The only metabolic effect of undoubted clinical importance is weight gain . </li></ul><ul><li>- Minor alterations of lipid metabolism , fluid/nitrogen balance , glucose tolerance , steroid metabolism , and immune function have been recorded but seem to be of no clinical significance. </li></ul><ul><li>- Fewer data have been published on the metabolic effects of NET-EN, but its effect on most biochemical functions appears to be similar to that of DMPA. </li></ul>www.freelivedoctor.com
  25. 25. Cardiovascular Effect <ul><li>Data are insufficient to indicate whether there is any relation between DMPA use and cardiovascular complications. </li></ul><ul><li>Results of a WHO study suggest that there is little or no increased risk of cardiovascular disease associated with the use of progestagen-only injectables, although further investigation is needed into a possible increased risk of stroke among women with high blood pressure. </li></ul>www.freelivedoctor.com
  26. 26. RETURN OF FERTILITY <ul><li>Fertility is not impaired after discontinuation of DMPA or NET-EN although its return is delayed . </li></ul><ul><li>The average time between the last DMPA injection and conception is about nine months , including the three months during which the injection is effective. </li></ul><ul><li>More than 80% of women become pregnant within one year of discontinuing DMPA and 90% within two years . </li></ul><ul><li>The few data on NET-EN suggest that fertility returns more quickly with this agent. </li></ul>www.freelivedoctor.com
  27. 27. www.freelivedoctor.com
  28. 28. World Health Organization (WHO) developed eligibility criteria for the use of various contraceptive methods . <ul><li>Category 1 : A condition for which there is no restriction for the use of the contraceptive method. </li></ul><ul><li>Category 2 : A condition where the advantages of using the method generally outweigh the theoretical or proven risks. </li></ul><ul><li>Category 3 : A condition where the theoretical or proven risks usually outweigh the advantages of using the method. </li></ul><ul><li>Category 4 : A condition which represents an unacceptable health risk if the contraceptive method is used. </li></ul>www.freelivedoctor.com
  29. 29. Contra-indications (category 4): <ul><li>POIs should not be used in the presence of: </li></ul><ul><li>Confirmed or suspected pregnancy </li></ul><ul><li>Malignant disease of the breast </li></ul>www.freelivedoctor.com
  30. 30. Conditions requiring careful consideration (category 3): <ul><li>POIs should generally not be used in the presence of: </li></ul><ul><li>Diabetes with vascular disease or of >20 years’ duration </li></ul><ul><li>Cerebrovascular or coronary artery disease </li></ul><ul><li>Acute liver disease </li></ul><ul><li>4.benign or malignant liver tumours </li></ul><ul><li>Severe hypertension/ (BP>180/110 mm Hg) </li></ul><ul><li>Hypertension with vascular disease </li></ul><ul><li>Focal migraine . </li></ul><ul><li>severe cirrhosis </li></ul>www.freelivedoctor.com
  31. 31. Other Conditions (category 2) <ul><li>- Women with mild to moderate hypertension, diabetes (without vascular complications), hyperlipidaemias, or mild (compensated) cirrhosis can generally use POIs. </li></ul><ul><li>- Careful screening and appropriate monitoring will allow the benefits of using POIs to outweigh any potential risks. </li></ul>www.freelivedoctor.com
  32. 32. COMBINED INJECTABLE CONTRACEPTIVES www.freelivedoctor.com
  33. 33. Mode of Action <ul><li>Combined injectable contraceptives (CICs) exert their contraceptive effect mainly by suppressing ovulation . </li></ul><ul><li>In addition, thickening of the cervical mucus (mainly due to the progestagen) presents an obstacle to sperm penetration. </li></ul><ul><li>The receptivity of endometrium to the blastocyst is also reduced. </li></ul>www.freelivedoctor.com
  34. 34. Efficacy <ul><li>In clinical trials, Cyclofem /Cycloprovera and Mesigyna/Norigynon have both proved highly effective contraceptives </li></ul><ul><li>With 12-month failure rates of 0.2% or less for Cyclofem and 0.4% for Mesigyna . </li></ul>www.freelivedoctor.com
  35. 35. Beneficial Effects <ul><li>A single injection of a CIC can provide highly effective protection against pregnancy for one month . </li></ul><ul><li>Delivery is simple and independent of coitus, and in general CICs are associated with better cycle control than POIs. </li></ul>www.freelivedoctor.com
  36. 36. Side-Effects <ul><li>In clinical trials, side-effects of CICs included irregular bleeding, amenorrhoea, heavy bleeding, prolonged bleeding, headaches, dizziness, and body weight changes. </li></ul><ul><li>However, these side-effects are much less common than with the use of POIs. </li></ul>www.freelivedoctor.com
  37. 37. Return of Fertility <ul><li>The return of fertility following CIC use is noticeably shorter than that observed for POIs. </li></ul><ul><li>More than 50% of women become pregnant within six months of discontinuing CICs and 80% within one year. </li></ul>www.freelivedoctor.com
  38. 38. Eligibility Criteria <ul><li>Until sufficient clinical data become available, the eligibility criteria for the use of combined injectable contraceptives are based on data from combined oral contraceptives </li></ul>www.freelivedoctor.com
  39. 39. www.freelivedoctor.com
  40. 40. Adolescents <ul><li>Injectable contraceptives have important advantages in adolescents; however, in those under 16 years of age there are concerns regarding the hypo-oestrogenic effects of POIs, which may affect the post-menarche increase of bone mineral density. </li></ul>www.freelivedoctor.com
  41. 41. Women Over 35 <ul><li>POIs and CICs can be used by most healthy women over 35 . </li></ul><ul><li>Any increase in risk of cardiovascular disease will be minimal for these women if they do not smoke and have no other risk factors, such as hypertension or diabetes. </li></ul>www.freelivedoctor.com
  42. 42. Postpartum (in Breast feeding Women) <ul><li>If a woman wishes to start injectable contraception during breastfeeding a POI should be recommended . </li></ul><ul><li>DMPA and NET-EN have no apparent negative influence on milk production or the duration of lactation ; and infants whose mothers have received DMPA while breastfeeding seem to develop normally, both physically and mentally. </li></ul>www.freelivedoctor.com
  43. 43. Postpartum (in Breast feeding Women) <ul><li>The question of possible consequences of the transfer of the injectable steroid to the breastfed infant has yet to be resolved . </li></ul><ul><li>The amounts of steroid transmitted in the milk and absorbed by the infant are known to be small. </li></ul>www.freelivedoctor.com
  44. 44. Postpartum (in Breast feeding Women) <ul><li>Short-term follow-up studies of children breastfed by mothers using progestagen-only contraceptives have given reassuring results, but longer-term studies are yet to be evaluated. </li></ul><ul><li>It is recommended that breastfeeding women should not start POIs before the sixth week postpartum . </li></ul>www.freelivedoctor.com
  45. 45. Postpartum (in Breastfeeding Women) <ul><li>There are no data on the effects of CIC formulations on the quantity and quality of breast milk or the duration of lactation. </li></ul><ul><li>Until such data become available, CICs should generally be withheld until six months after delivery or until the infant is weaned, whichever is the earlier </li></ul>www.freelivedoctor.com
  46. 46. Postpartum (in Non-Breast feeding Women) <ul><li>To avoid increasing the risk of thromboembolic complications in the postpartum period, CICs should not be used during the first three weeks after delivery. </li></ul><ul><li>After 21 days, blood coagulation and fibrinolysis are essentially back to normal. </li></ul><ul><li>POIs can be started at any time after delivery . </li></ul>www.freelivedoctor.com
  47. 47. Drug Interaction <ul><li>Drugs that induce liver enzymes may lessen the efficacy of hormonal contraceptives. </li></ul><ul><li>Such drugs which are commonly used in long-term treatments include the antibiotics rifampicin and griseofulvin and the anticonvulsants phenytoin , carbamazepine , and barbiturates. </li></ul>www.freelivedoctor.com
  48. 48. Prevention of STD/HIV Transmission <ul><li>Strict aseptic techniques should be maintained when giving the injections to avoid the risk of transmitting any infection including HIV. </li></ul><ul><li>Injectable contraceptives do not protect against STD/HIV infection. </li></ul><ul><li>Therefore, when there is a risk of sexual transmission of infection, condoms should always be used in addition to injectable contraceptives. </li></ul>www.freelivedoctor.com
  49. 49. Elective Surgery <ul><li>It is advisable to stop using CICs about four weeks before elective surgery that will involve prolonged immobilisation , and to restart them two weeks after the woman has returned to mobility. </li></ul><ul><li>Alternative effective contraception, including POIs, should be advised during this time. </li></ul><ul><li>In emergency procedures, the surgeon may consider prophylactic anticoagulant measures </li></ul>www.freelivedoctor.com
  50. 50. Sickle Cell Disease <ul><li>Either POIs or CICs can be used by women with sickle cell disease but POIs are a more suitable choice. </li></ul><ul><li>In addition to their contraceptive effect, there is some evidence of benefit on the disease itself. </li></ul>www.freelivedoctor.com
  51. 51. Counselling <ul><li>Clients considering the use of injectable contraception should be clearly informed about the advantages and disadvantages of the agents, their side-effects, their cost, and the alternative contraceptive options. </li></ul><ul><li>Where once-a-month injectables are available, clients should be told about the differences between these injectables and POIs. </li></ul><ul><li>Women who desire a rapid return to fertility on discontinuation of their contraceptive should be advised to use CICs where available or another method. </li></ul>www.freelivedoctor.com
  52. 52. some misconceptions about injectables www.freelivedoctor.com
  53. 53. Do injectable contraceptives cause infertility ? <ul><li>No. </li></ul><ul><li>Although a woman's return to fertility can be delayed after injectables are discontinued, injectables do not damage fertility. </li></ul>www.freelivedoctor.com
  54. 54. Do injectable contraceptives increase cancer risks ? <ul><li>No. </li></ul><ul><li>Overall increase in cancer risk has not been demonstrated in long-term, multicountry studies of injectable users. </li></ul>www.freelivedoctor.com
  55. 55. When amenorrhea occurs, does menstrual blood build up in the body, leading to disease ? <ul><li>No. </li></ul><ul><li>Amenorrhea is not a  health risk. </li></ul><ul><li>It does not cause  blood to build up in the body. </li></ul>www.freelivedoctor.com
  56. 56. Can injectable contraceptives transmit disease ? <ul><li>No. </li></ul><ul><li>Injectable contraceptives are sterile preparations that are free from disease- causing agents. </li></ul><ul><li>Contaminated needles and syringes used to administer injectables can transmit disease, however . </li></ul>www.freelivedoctor.com
  57. 57. special injection techniques www.freelivedoctor.com
  58. 58. <ul><li>Injectable contraceptives are administered using deep intramuscular injection techniques. </li></ul><ul><li>The injection site should not be massaged afterwards, since this may accelerate absorption of the drug. </li></ul>www.freelivedoctor.com
  59. 59. <ul><li>Because DMPA is an aqueous suspension, a DMPA vial must be shaken vigorously before it is loaded into the syringe, to resuspend any active ingredient in the bottom of the vial. </li></ul><ul><li>The syringe should then be checked to ensure that it contains the correct dosage. </li></ul>www.freelivedoctor.com
  60. 60. <ul><li>NET-EN is an oil-based solution that needs special care to ensure that all the solution is both loaded and injected without leakage. </li></ul><ul><li>Warming the vial to body temperature makes it easier to draw into the syringe. </li></ul><ul><li>Since Mesigyna is an oil-based solution similar to NET-EN , the same attention to leakage applies. </li></ul>www.freelivedoctor.com
  61. 61. When can the initial injection be given ? www.freelivedoctor.com
  62. 62. Progestogen -Only Injectables <ul><li>DMPA and NET-EN : </li></ul><ul><li>During the first 7 days of the menstrual cycle. </li></ul><ul><li>Injectables will be immediately effective. </li></ul><ul><li>Immediately after abortion. </li></ul><ul><li>At other times in a menstrual cycle as long as the possibility of pregnancy is ruled out. </li></ul><ul><li>At 6 weeks postpartum . </li></ul>www.freelivedoctor.com
  63. 63. Combined Injectables Mesigyna <ul><li>During the first 5 days of the menstrual cycle. </li></ul><ul><li>Injectables will be immediately effective. </li></ul><ul><li>Immediately after abortion. </li></ul><ul><li>At other times in a menstrual cycle as long as the possibility of pregnancy is ruled out. </li></ul><ul><li>At 6 months postpartum . </li></ul>www.freelivedoctor.com
  64. 64. Margin for the follow-up re-injection www.freelivedoctor.com
  65. 65. <ul><li>Progestogen-Only Injectables DMPA and NET-EN: up to 2 weeks (14 days) early or late </li></ul><ul><li>Combined Injectables Mesigyna: </li></ul><ul><li>Up to 3 days early or late </li></ul>www.freelivedoctor.com
  66. 66. Breast feeding <ul><li>Progestogen-Only Injectables DMPA and NET-EN: </li></ul><ul><li>Suitable for women who are breastfeeding at 6 weeks postpartum. </li></ul><ul><li>Combined Injectables Mesigyna: </li></ul><ul><li>Not suitable for women who are fully breast feeding until 6 months postpartum. </li></ul>www.freelivedoctor.com
  67. 67. Thank you www.freelivedoctor.com

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