To avoid unintended pregnancy, women in the UK need to consistently use reliable contraception for over 30 years. The long-acting reversible contraceptive methods compromise the progestogen-only implant, the progestogen-only injectable contraceptive, the copper-bearing intra-uterine device and the levonorgestrel-releasing intra-uterine system. These methods of contraception are highly reliable in pregnancy prevention, and are amongst the medically safest methods for users. Despite this, these long-acting methods are used by less than 10% of the UK population. National guidance has advised that increasing uptake of these long-acting methods will reduce the unplanned pregnancy rate. In addition, these methods are more cost effective than the oral contraceptive even at 1 year of use. Obstetricians and gynaecologists frequently come into contact with women requiring contraceptive advice, and should have a sound knowledge of the long-acting methods.
A need for contraception
In the United Kingdom, the average age for first sexual intercourse is 16 years, for young women and young men. However, women do not bear their first child until the age of 30 on average, and have a total fertility rate of under 2. Combined with an average age of menopause of 51 years, today’s woman requires to use contraception for over 30 years of her life.
The majority of women in the reproductive age group in the UK are using at least one form of contraception. In 2003–04, almost a quarter of women were relying on sterilisation (11% female and 12% male partners), 25% were using a contraceptive pill and 23% the male condom. The long-acting reversible contraceptive (LARC) methods were used by less than 10% of women, with 4% using the copper intra-uterine device (IUD), 3% the progestogen-only injectable contraceptive (POIC) or implant and 1% the progestogen-only intra-uterine system (IUS) ( Table 1 ).
| Method | % using method |
|---|---|
| Oral contraceptive pill | 25 |
| Male condom | 23 |
| Female sterilisation | 11 |
| Male sterilisation | 12 |
| IUD | 4 |
| Injectable/implant | 3 |
| IUS | 1 |
| Withdrawal | 3 |
| Total using at least one method | 75 |
Contraceptive methods vary in effectiveness, and effectiveness in practice (typical use) varies from perfect use. Table 2 illustrates the variation in chance of pregnancy in the first year of use of the commonly used methods, when perfect use is compared with typical use. The LARC methods and sterilisation show least variation between typical and perfect use. The implant and intra-uterine methods once inserted require no further action on behalf of the user, other than to return for method replacement at the end of the licensed period of use. The injectable method, although still very effective, depends on the user returning regularly for repeat injection. The risk of pregnancy in the first year of use for oral contraceptive users varies greatly for perfect use (0.3%) compared to typical use (8%). A number of studies have shown that many oral contraceptive users have poor compliance with the method. In one study, almost half (47%) of women reported missing one or more pills per cycle. Another study, which used electronic diaries to measure compliance, demonstrated that 63% of women missed at least one pill in the first cycle of use, and 74% missed in the second cycle. Likewise, even greater variation exists for methods which rely upon motivation with every act of intercourse, such as condoms or withdrawal. Incorrect, inconsistent or absent use of contraception leads to unplanned pregnancy. Unintended pregnancy is common in the UK; up to a third of children born are a result of an unplanned pregnancy. Unplanned pregnancies may also result in abortion. In the UK in 2008, over 200 000 abortions were performed. In England and Wales, 195 296 therapeutic abortions occurred, with 33% being performed in women who had already experienced at least one previous abortion. In Scotland, 27.3% of 13 817 abortions were in women who had previously had an abortion.
| Method | Typical use | Perfect use |
|---|---|---|
| Oral contraception | 8 | 0.3 |
| Male condom | 15 | 2 |
| Female sterilisation | 0.5 | 0.5 |
| Male sterilisation | 0.15 | 0.1 |
| IUD | 0.8 | 0.6 |
| Injectable | 3 | 0.3 |
| Implant | 0.05 | 0.05 |
| IUS | 0.1 | 0.1 |
| Withdrawal | 27 | 4 |
In 2005, the National Institute for Health and Clinical Excellence (NICE) clinical guideline on LARC was published. This guideline defined LARC as reversible methods of contraception, which require administration less than once per month. In the UK, LARC methods therefore compromise:
- •
Progestogen-only subdermal implant (POSDI),
- •
Progestogen-only injectable contraceptive (POIC)
- •
copper-bearing (IUD) and
- •
levonorgestrel-releasing (IUS).
The guidance advised clinicians that women requiring contraception should be offered a choice of all methods, including the LARC methods. In addition, an economic analysis demonstrated that all LARC methods are more cost effective than the combined oral contraceptive pill even at 1 year of use. Of particular note, it was also demonstrated that increasing the uptake of LARC will decrease the numbers of unintended pregnancies. Thus, there exists the potential to reduce the number of abortions, by increasing the general uptake of LARC, but in addition, to reduce the repeat abortion rate by targeting women presenting for their first abortion. Obstetricians and gynaecologists are frequently in a position to advise women about their contraceptive options, for example, postnatally, in the gynaecology clinic, and in the abortion care setting, and should be knowledgeable about LARC methods.
The UK Medical Eligibility Criteria for Contraceptive Use (UKMEC) published by the Clinical Effectiveness Unit (CEU) of the Faculty of Sexual and Reproductive Healthcare (FSRH) provide evidence-based recommendations to allow an appropriate method of contraception to be selected without imposing unnecessary restriction. Health professionals supplying contraception should be familiar with this categorisation. Table 3 summarises the categories defined in UKMEC, and will be referred to for each of the LARC methods in turn.
| UKMEC Category | Definition of Category |
|---|---|
| 1 | A condition for which there is no restriction for use of the contraceptive method |
| 2 | A condition for which the advantages of using the method generally outweigh the theoretical or proven risks |
| 3 | A condition where the theoretical or proven risks usually outweigh the advantages of using the method a |
| 4 | A condition which represents an unacceptable health risk if the contraceptive method is used |
a The provision of a method to a woman with a condition given UKMEC Category 3 requires expert clinical judgement and/or referral to a specialist contraceptive provider since use of the method is not usually recommended unless other methods are not available or not acceptable.
Progestogen-only Subdermal Implants (POSDI)
There is one POSDI currently licensed for contraception in the UK, manufactured as Implanon ® . Implanon is a single non-biodegradable rod, measuring 40 × 2 mm, and containing 68 mg of etonogestrel within a rate-limiting ethylene vinyl acetate membrane. It is effective for contraception for 3 years. A radio-opaque implant (containing 3% barium sulphate) in an ethylene vinyl acetate membrane with 68 mg etonogestrel is scheduled to be released onto the UK market in late 2010. It will be manufactured as Nexplanon and will replace Implanon. Norplant ® was manufactured in the UK until 1999, and is a six-rod device, containing levonorgestrel and effective for 5 years. Although no longer available in the UK, women from other countries may still be using Norplant and may present in the UK for removal. Jadelle ® is a two-rod levonorgestrel-releasing POSDI, effective for 5 years, and is manufactured in over 30 countries, although not in the UK. Again, women using Jadelle may be present in the UK.
Mode of action
Implanon releases 60–70 μg etonogestrel/day initially, falling to 30–40 μg/day in the second year, and then to 25–30 μg/day by the end of the third year. The principal mode of action is suppression of ovulation sustained throughout the 3 years, although there are additional progestogenic anti-fertility effects, including thickening of cervical mucus to prevent sperm penetration and inhibition of endometrial development.
Contraceptive efficacy
Two meta-analyses, comparing Implanon and Norplant, looked at 74,000 cycles of use in over 2000 women and reported no pregnancies in either group at 3 years. Several non-comparative studies again confirmed no pregnancies with Implanon use, the largest of these studies involving 1200 woman-years of use.
Post-marketing surveillance in both Australia and the UK has reported occasional pregnancies with Implanon use. However, most of these pregnancies appear to have arisen as a result of inappropriate timing of insertion, failure of insertion or drug interaction. A small number of apparent genuine failures have been identified, and the overall anticipated pregnancy rate in the NICE guidance is given as <1 in 1000 over 3 years of use.
Eligibility for the method
As a low-dose progestogen-only method of contraception, Implanon is suitable for most women requesting contraception. In particular, it can be safely used by women of all reproductive ages, from menarche to menopause, and in those with hypertension, obesity, a history of venous thrombo-embolism (VTE) and diabetes, including long-term or complicated diabetes. Implanon can be used in postnatal women, including those who are breast-feeding, and in women with gestational trophoblastic disease.
There are very few conditions identified in UKMEC as category 3, where the risks usually outweigh the benefits. In some of these conditions, after consultation with a specialist contraceptive provider, the method may be supplied depending upon acceptability or otherwise of other methods, and upon the risks of pregnancy with the condition in question:
- •
Current or arising ischaemic heart disease, which occurs with the POSDI in situ .
- •
Stroke which arises with the POSDI in situ .
- •
Unexplained vaginal bleeding where there is suspicion of serious condition, prior to investigation.
- •
Past history of breast cancer (over 5 years ago).
- •
Severe decompensated liver cirrhosis.
- •
Liver adenoma, both benign and malignant.
- •
Systemic lupus erythematosis with antiphospholipid antibodies.
Current breast cancer (within 5 years) is the ‘only’ UKMEC category 4 condition, prohibiting use of the method.
Timing of insertion
Post-abortion
Each of the Royal College of Obstetricians and Gynaecologists (RCOG) guidance on the Care of Women Requesting Induced Abortion, NICE LARC guidance and the CEU guidance on progestogen-only implants advise that Implanon can be inserted immediately following surgical or medical abortion in both the first and second trimesters. As long as the Implanon is inserted within the first 5 days after abortion, no additional contraception is required. If insertion is delayed beyond 5 days after abortion, then additional contraception should be advised until the implant has been in situ for 7 days.
Post-partum
Implanon can be used without restriction in post-partum women, in both breast-feeding and non-breast-feeding. There has been no effect on breast milk volume or composition, or on infant development when compared to women using a copper IUD. When Implanon is inserted up to and including day 21 post-partum, there is no need for additional contraception, but if inserted beyond the 21st post-partum day, additional contraception should be advised until the implant has been in situ for 7 days.
In the normal menstrual cycle
When Implanon is inserted up to and including day 5 of a normal menstrual cycle, the contraceptive effect is immediate and no additional contraception is required. Implanon can be inserted later in the menstrual cycle, provided there has been no risk of conception. In such circumstances, additional contraception should be advised until the implant has been in situ for 7 days.
Following other methods of contraception
If a woman has been correctly using the combined oral contraceptive pill, the progestogen-only pill, a progestogen-only injectable or a pre-existing POSDI, then Implanon can be inserted, and the contraceptive effect will be immediate. If Implanon is inserted in a woman currently using the IUS, then the IUS should be retained for 7 days after Implanon insertion. The same follows for the IUD, unless the Implanon is inserted within the first 5 days of the menstrual cycle.
Administration technique
Implanon is inserted subdermally 8–10 cm above the medial epicondyle of the humerus, conventionally in the non-dominant arm. It should be inserted under aseptic conditions, wearing sterile gloves. Local anaesthetic should be used prior to insertion, usually 2 ml of 1% lignocaine is sufficient. The presence of the implant should be confirmed by palpation after insertion. Resuscitation equipment should be available, in the rare event of anaphylaxis. Routine follow-up is not required after Implanon insertion, but women should be advised to return if they have concerns. The woman should be advised when she is due to return for removal of the Implanon at the end of 3 years. Implanon clinicians are recommended to complete and maintain the FSRH Letter of Competence in Subdermal Implants. Nurses can also train to become Implanon inserters/removers and are recommended to obtain Royal College of Nursing accreditation.
Side effects
Changes in bleeding patterns are frequently reported by Implanon users, and are reported to be more common in the first few months of use. One retrospective study from Scotland found that 25% of women discontinued Implanon within the first year of use, mainly because of bleeding problems (62% of removal was for this reason). A further UK retrospective study showed a cumulative removal rate at 3 years of 12%, due to bleeding problems. Overall, about 20% of users can expect amenorrhoea, which will be viewed as beneficial by many women. Around 45% will experience bleeding which is infrequent, frequent or prolonged. Dysmenorrhoea is usually improved. Women who present with persistent problematic bleeding with Implanon, or with a change in bleeding pattern, should be assessed for risk of sexually transmitted infection, and have significant gynaecological pathology excluded. There is little evidence on strategies to manage problematic bleeding with Implanon, but there is some evidence from Norplant users that mefenamic acid or ethinyl oestradiol (can be given as combined contraceptive pill) offer some benefit.
Acne is common in younger women, whether contraceptive users or not. The combined contraceptive pill benefits acne, and thus some women changing from a pill to Implanon may notice a deterioration in acne. A non-comparative study showed that acne occurred or worsened in 12.6% of Implanon users, but improved in 12.8% of Implanon users.
Headache has been reported in several studies on Implanon users. A UK study reported headache as a side effect in 1% of users at 3 years, and a US study reported headache in 24% of users at 2 years. However, headache is a common symptom in the general population, with up to 70% experiencing headache in the preceding 3 months. Thus, it is difficult to confirm a causal link between Implanon use and headache.
Weight change is a common concern in women of reproductive age. A retrospective UK study reported weight gain in 4% of Implanon users at 3 years of use. A French study showed no change in weight in 52% of Implanon users, weight gain in 37% and weight loss in 11%. It seems likely that there is no causal relationship between Implanon use and weight change.
In a similar manner, mood change has been reported in a small number of users in some retrospective studies, and accounted for the reason for Implanon removal in 9% of users in one UK study.
In light of concerns about the effect of progestogen-only injectables on bone mineral density, a cohort study compared changes in bone mineral density from baseline in Implanon users and copper IUD users, and found no significant difference over 2 years.
Etonogestrel is metabolised through the liver, and serum concentrations may be reduced, and contraceptive efficacy reduced, when liver enzyme-inducing medications are used concurrently. Such drugs will include some of the anti-epilepsy drugs such as carbamazepine and phenytoin, liver enzyme-inducing antibiotics such as rifampicin, and some of the anti-retroviral drugs used in the management of human immunodeficiency virus (HIV) disease. When liver enzyme inducers are used in the short term, additional barrier contraception should be advised for the duration of the drug therapy, and for 4 weeks after cessation of the concomitant drug. When long-term use of a liver enzyme inducer is necessary, the woman may wish to consider use of a method unaffected by the medication. The efficacy of POSDI is not affected by non-liver enzyme-inducing antibiotics.
There are no known teratogenic effects if a pregnancy was to occur with a POSDI in situ . However, good practice would be to remove the implant if the pregnancy is to be continued. If the woman opts for termination of the pregnancy, the implant can be retained.
Progestogen-only Subdermal Implants (POSDI)
There is one POSDI currently licensed for contraception in the UK, manufactured as Implanon ® . Implanon is a single non-biodegradable rod, measuring 40 × 2 mm, and containing 68 mg of etonogestrel within a rate-limiting ethylene vinyl acetate membrane. It is effective for contraception for 3 years. A radio-opaque implant (containing 3% barium sulphate) in an ethylene vinyl acetate membrane with 68 mg etonogestrel is scheduled to be released onto the UK market in late 2010. It will be manufactured as Nexplanon and will replace Implanon. Norplant ® was manufactured in the UK until 1999, and is a six-rod device, containing levonorgestrel and effective for 5 years. Although no longer available in the UK, women from other countries may still be using Norplant and may present in the UK for removal. Jadelle ® is a two-rod levonorgestrel-releasing POSDI, effective for 5 years, and is manufactured in over 30 countries, although not in the UK. Again, women using Jadelle may be present in the UK.
Mode of action
Implanon releases 60–70 μg etonogestrel/day initially, falling to 30–40 μg/day in the second year, and then to 25–30 μg/day by the end of the third year. The principal mode of action is suppression of ovulation sustained throughout the 3 years, although there are additional progestogenic anti-fertility effects, including thickening of cervical mucus to prevent sperm penetration and inhibition of endometrial development.
Contraceptive efficacy
Two meta-analyses, comparing Implanon and Norplant, looked at 74,000 cycles of use in over 2000 women and reported no pregnancies in either group at 3 years. Several non-comparative studies again confirmed no pregnancies with Implanon use, the largest of these studies involving 1200 woman-years of use.
Post-marketing surveillance in both Australia and the UK has reported occasional pregnancies with Implanon use. However, most of these pregnancies appear to have arisen as a result of inappropriate timing of insertion, failure of insertion or drug interaction. A small number of apparent genuine failures have been identified, and the overall anticipated pregnancy rate in the NICE guidance is given as <1 in 1000 over 3 years of use.
Eligibility for the method
As a low-dose progestogen-only method of contraception, Implanon is suitable for most women requesting contraception. In particular, it can be safely used by women of all reproductive ages, from menarche to menopause, and in those with hypertension, obesity, a history of venous thrombo-embolism (VTE) and diabetes, including long-term or complicated diabetes. Implanon can be used in postnatal women, including those who are breast-feeding, and in women with gestational trophoblastic disease.
There are very few conditions identified in UKMEC as category 3, where the risks usually outweigh the benefits. In some of these conditions, after consultation with a specialist contraceptive provider, the method may be supplied depending upon acceptability or otherwise of other methods, and upon the risks of pregnancy with the condition in question:
- •
Current or arising ischaemic heart disease, which occurs with the POSDI in situ .
- •
Stroke which arises with the POSDI in situ .
- •
Unexplained vaginal bleeding where there is suspicion of serious condition, prior to investigation.
- •
Past history of breast cancer (over 5 years ago).
- •
Severe decompensated liver cirrhosis.
- •
Liver adenoma, both benign and malignant.
- •
Systemic lupus erythematosis with antiphospholipid antibodies.
Current breast cancer (within 5 years) is the ‘only’ UKMEC category 4 condition, prohibiting use of the method.
Timing of insertion
Post-abortion
Each of the Royal College of Obstetricians and Gynaecologists (RCOG) guidance on the Care of Women Requesting Induced Abortion, NICE LARC guidance and the CEU guidance on progestogen-only implants advise that Implanon can be inserted immediately following surgical or medical abortion in both the first and second trimesters. As long as the Implanon is inserted within the first 5 days after abortion, no additional contraception is required. If insertion is delayed beyond 5 days after abortion, then additional contraception should be advised until the implant has been in situ for 7 days.
Post-partum
Implanon can be used without restriction in post-partum women, in both breast-feeding and non-breast-feeding. There has been no effect on breast milk volume or composition, or on infant development when compared to women using a copper IUD. When Implanon is inserted up to and including day 21 post-partum, there is no need for additional contraception, but if inserted beyond the 21st post-partum day, additional contraception should be advised until the implant has been in situ for 7 days.
In the normal menstrual cycle
When Implanon is inserted up to and including day 5 of a normal menstrual cycle, the contraceptive effect is immediate and no additional contraception is required. Implanon can be inserted later in the menstrual cycle, provided there has been no risk of conception. In such circumstances, additional contraception should be advised until the implant has been in situ for 7 days.
Following other methods of contraception
If a woman has been correctly using the combined oral contraceptive pill, the progestogen-only pill, a progestogen-only injectable or a pre-existing POSDI, then Implanon can be inserted, and the contraceptive effect will be immediate. If Implanon is inserted in a woman currently using the IUS, then the IUS should be retained for 7 days after Implanon insertion. The same follows for the IUD, unless the Implanon is inserted within the first 5 days of the menstrual cycle.
Administration technique
Implanon is inserted subdermally 8–10 cm above the medial epicondyle of the humerus, conventionally in the non-dominant arm. It should be inserted under aseptic conditions, wearing sterile gloves. Local anaesthetic should be used prior to insertion, usually 2 ml of 1% lignocaine is sufficient. The presence of the implant should be confirmed by palpation after insertion. Resuscitation equipment should be available, in the rare event of anaphylaxis. Routine follow-up is not required after Implanon insertion, but women should be advised to return if they have concerns. The woman should be advised when she is due to return for removal of the Implanon at the end of 3 years. Implanon clinicians are recommended to complete and maintain the FSRH Letter of Competence in Subdermal Implants. Nurses can also train to become Implanon inserters/removers and are recommended to obtain Royal College of Nursing accreditation.
Side effects
Changes in bleeding patterns are frequently reported by Implanon users, and are reported to be more common in the first few months of use. One retrospective study from Scotland found that 25% of women discontinued Implanon within the first year of use, mainly because of bleeding problems (62% of removal was for this reason). A further UK retrospective study showed a cumulative removal rate at 3 years of 12%, due to bleeding problems. Overall, about 20% of users can expect amenorrhoea, which will be viewed as beneficial by many women. Around 45% will experience bleeding which is infrequent, frequent or prolonged. Dysmenorrhoea is usually improved. Women who present with persistent problematic bleeding with Implanon, or with a change in bleeding pattern, should be assessed for risk of sexually transmitted infection, and have significant gynaecological pathology excluded. There is little evidence on strategies to manage problematic bleeding with Implanon, but there is some evidence from Norplant users that mefenamic acid or ethinyl oestradiol (can be given as combined contraceptive pill) offer some benefit.
Acne is common in younger women, whether contraceptive users or not. The combined contraceptive pill benefits acne, and thus some women changing from a pill to Implanon may notice a deterioration in acne. A non-comparative study showed that acne occurred or worsened in 12.6% of Implanon users, but improved in 12.8% of Implanon users.
Headache has been reported in several studies on Implanon users. A UK study reported headache as a side effect in 1% of users at 3 years, and a US study reported headache in 24% of users at 2 years. However, headache is a common symptom in the general population, with up to 70% experiencing headache in the preceding 3 months. Thus, it is difficult to confirm a causal link between Implanon use and headache.
Weight change is a common concern in women of reproductive age. A retrospective UK study reported weight gain in 4% of Implanon users at 3 years of use. A French study showed no change in weight in 52% of Implanon users, weight gain in 37% and weight loss in 11%. It seems likely that there is no causal relationship between Implanon use and weight change.
In a similar manner, mood change has been reported in a small number of users in some retrospective studies, and accounted for the reason for Implanon removal in 9% of users in one UK study.
In light of concerns about the effect of progestogen-only injectables on bone mineral density, a cohort study compared changes in bone mineral density from baseline in Implanon users and copper IUD users, and found no significant difference over 2 years.
Etonogestrel is metabolised through the liver, and serum concentrations may be reduced, and contraceptive efficacy reduced, when liver enzyme-inducing medications are used concurrently. Such drugs will include some of the anti-epilepsy drugs such as carbamazepine and phenytoin, liver enzyme-inducing antibiotics such as rifampicin, and some of the anti-retroviral drugs used in the management of human immunodeficiency virus (HIV) disease. When liver enzyme inducers are used in the short term, additional barrier contraception should be advised for the duration of the drug therapy, and for 4 weeks after cessation of the concomitant drug. When long-term use of a liver enzyme inducer is necessary, the woman may wish to consider use of a method unaffected by the medication. The efficacy of POSDI is not affected by non-liver enzyme-inducing antibiotics.
There are no known teratogenic effects if a pregnancy was to occur with a POSDI in situ . However, good practice would be to remove the implant if the pregnancy is to be continued. If the woman opts for termination of the pregnancy, the implant can be retained.
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