65 Sharon T. Cameron1,2 1 Faculty of Sexual and Reproductive Healthcare, Chalmers Centre, NHS Lothian, Edinburgh, UK 2 University of Edinburgh, Edinburgh, UK The average age of first intercourse in women is 16 years and average age of menopause is 51, so most women will need to use contraception for more than 30 years. Use of contraception in the UK is high. Despite this, unintended pregnancy is common, with abortion rates of between 11.6 and 16 per 1000 women of reproductive age in the UK in 2016 [1,2]. Around three‐quarters of women presenting for abortion report having used a method of contraception around the time of conception, but the methods used are mostly of low effectiveness, or used inconsistently or incorrectly [3]. It is estimated that 30% of pregnancies ending in birth were unintended at conception [4]. Unintended pregnancies in the year following birth are also common. If a birth to conception interval is less than 12 months (short inter‐pregnancy interval), then this increases the risk of preterm birth and neonatal death [5]. Obstetricians and gynaecologists should take key opportunities such as the antenatal period and routine gynaecological consultations to discuss effective contraception and provide methods where possible. The most effective methods comprise long‐acting reversible contraception (LARC), including intrauterine contraception, implants and injectables. Greater uptake of LARC in the UK could prevent more unintended pregnancies, abortions and prevent short inter‐pregnancy intervals for more women. The effectiveness of a method of contraception is expressed by the failure rates associated with its use. Effectiveness depends on efficacy of the method, compliance and continuation with the method. Perfect‐ and typical‐use failure rates of methods (based on percentage of couples experiencing an unintended pregnancy during the first year of use) are shown in Table 65.1 [6]. Methods that make no demands on compliance after insertion have perfect‐use and typical‐use failure rates that are virtually the same. Compliance with oral contraception is not easy. In one study, almost 63% of users missed one or more pills in the first cycle, and 74% in the second cycle of use [7]. Typical‐use failure rates are even higher with condoms, which rely on correct use with every act of intercourse. The progestogen‐only injectable lasts 13 weeks but correct use demands the motivation and organizational skills required to receive a repeat dose. Intrauterine contraception (IUC) and implants are removed by a healthcare professional and are independent of user compliance for effectiveness. Table 65.1 Effectiveness of contraceptive methods: percentage of women experiencing an unintended pregnancy during the first year of use and percentage continuing use at the end of the first year (USA) [6]. Discontinuation rates are higher for methods which do not require removal by a provider. Data from the USA indicate that approximately 50% of women discontinue a pill or injectable within the first year of use, whereas approximately 80% of women continue the implant or IUC at 12 months [6]. Reasons for discontinuation are often associated with perceived risks and real or perceived side effects. Pregnancy rates are still often described by the Pearl index, the number of unintended pregnancies divided by the number of woman‐years of exposure to the risk of pregnancy while using the method. For long‐acting methods of contraception such as IUC and implants, pregnancy rates with time (cumulative pregnancy rates) are often reported. Most contraceptive users are young and healthy and can use all contraceptives safely. However, some medical conditions are associated with real or theoretical health risks with certain contraceptives. The World Health Organization (WHO) developed a system addressing medical eligibility criteria (MEC) for contraceptive use (WHO MEC) [8]; this has been adapted by the Faculty of Sexual and Reproductive Healthcare (FSRH) for the UK setting (UK MEC) [9]. Using evidence‐based systematic reviews, conditions are classified into one of four categories (Table 65.2). Category 1 includes conditions for which there is no restriction for use of the method, while category 4 includes conditions that represent an unacceptable health risk if the contraceptive method is used (absolutely contraindicated). Category 2 indicates that the method may generally be used. Provision of a method to a woman with a category 3 condition requires careful clinical judgement since use of that method is not recommended unless there is no acceptable alternative. The initiation and continuation of a method of contraception is sometimes distinguished and classified in the UKMEC. Initiation of a method may be appropriate in women with certain medical conditions, but if a medical condition develops while using a method, then this raises concern over continuation since use of the method may have contributed to development of the condition. It is important to note that the UKMEC categories relate to the safety of use of a method of contraception by a woman with a particular medical condition or personal characteristic. The efficacy of contraception may be affected by the condition or by a medication required for the condition but the UKMEC category does not reflect this. Table 65.2 Definition of UK MEC categories. For each of the personal characteristics or medical conditions considered by the UK MEC, a category 1, 2, 3 or 4 is given. Many factors determine the method of contraception an individual chooses. These include age, fertility intentions, perceptions of effectiveness and of safety, familiarity and experience of others, ease of use and non‐contraceptive benefits. Women should be given accurate information about all methods for which they are medically eligible. Studies show that women welcome information in an audiovisual formats (DVD, tablet, phone app) and that this may enhance uptake of the most effective methods [10,11]. Intrauterine methods of contraception include the copper‐bearing intrauterine device (Cu‐IUD) and the levonorgestrel‐releasing intrauterine system (LNG‐IUS). IUC is amongst the most effective LARC methods (see Table 65.1). In addition, the Cu‐IUD can also be used for emergency contraception. Unfortunately, IUC is unpopular in many settings. More needs to be done to improve uptake, especially amongst young women at risk of unintended pregnancy [11]. Although the manufacturers have recommended durations of use for IUC, there is evidence that efficacy extends beyond these limits. The FSRH advises that any Cu‐IUD inserted at or after the age of 40 can be retained until contraception is no longer required, i.e. 1 year after menopause if last menstrual period (LMP) is in fifties, or 2 years after menopause if LMP is in forties [14]. The FSRH also advises that a 52‐mg LNG‐IUS inserted at 45 years can be retained for contraception for 7 years or if amenorrhoeic until the menopause. If the 52 mg LNG‐IUS is being used as part of hormone replacement therapy (i.e. progestogenic opposition to exogenous estradiol), then it must be replaced after 5 years. All IUC should eventually be removed. A large (>61 000 women) European prospective cohort observational study (European Active Surveillance Study, EURAS) of IUC reported that the 52‐mg LNG‐IUS had superior efficacy to Cu‐IUD, although the failure rate was low with both [15]. For LNG‐IUS, the Pearl index (pregnancies per 100 woman‐years) was 0.06 (95% CI 0.04–0.09) in LNG‐IUS users and 0.52 (95% CI 0.42–0.64) in the Cu‐IUD cohort. High efficacy is also reported for the 19.5 mg LNG‐IUS which has a pearl index of 0.29 (95% CI 0.16–0.5) and 13.5‐mg LNG‐IUS, with a Pearl index of 0.33 (95% CI 0.16–0.60). Both the Cu‐ IUD and LNG‐IUS work primarily by inhibiting fertilization due to the toxic effect of copper ions on ova and sperm, and LNG also has effects on sperm penetrability and transport. Both devices also prevent implantation; the Cu‐IUD exerts a local inflammatory reaction in the endometrium and the LNG‐IUS induces endometrial atrophy. LNG‐IUS also causes thickening of the cervical mucus, which prevents sperm entering the uterus. Effects of the 52‐mg and 13.5‐mg LNG‐IUS on endometrium and cervical mucus are similar. There are very few women for whom IUC is contraindicated. Current pelvic tuberculosis, endometrial or cervical cancer, symptomatic sexually transmitted infection (STI) or pelvic inflammatory disease (PID) are the UK MEC 4 conditions [9]. Women at risk of STIs and women with well‐controlled HIV on antiretrovirals can safely use IUC with safe sex and additional condom use promoted. Unexplained vaginal bleeding should be investigated before IUC insertion and a distorted uterine cavity (due for example to fibroids) may make insertion impossible. Although providers may be reluctant to offer IUC to nulliparous women or adolescents owing to myths that insertion will be difficult or carry higher risks, the best available evidence supports safety of use of IUC in these groups, and this is reflected in the UK MEC [9]. Rates of perforation with IUC are low (2 per 1000 insertions). Increased risks include inexperience of the clinician, breastfeeding and being less than 36 weeks’ post partum [14,16]. Sometimes the clinician will suspect perforation at the time of fitting IUC and if so the procedure should be abandoned. Alternatively, women may complain of lower pelvic pain, a change in bleeding pattern or give a history of painful insertion. Others have no symptoms and the diagnosis is made due to lost threads or pregnancy. Absent threads in an IUC user should be investigated by ultrasound. A pregnancy test should be performed and emergency contraception provided (if unprotected intercourse) and alternative contraception provided in the interim. If ultrasound confirms absence of a device within the uterus, then an abdominal X‐ray should be performed. If the IUC is visible on X‐ray then this indicates it must be within the abdominal cavity. In most cases the IUC can be retrieved laparoscopically as an elective procedure. It is reported that 1 in 20 IUC devices will be expelled, usually in the 3 months after insertion [14]. Similar expulsion rates are reported for the Cu‐IUD and LNG‐IUS. With increasing use of ultrasound, it is not uncommon for an ultrasound report to state that an IUC is ‘low lying’ within the uterus. Unfortunately, there is no good evidence to determine if non‐fundally placed IUC provides effective contraceptive cover. The clinician should manage such cases on an individual basis along with the woman’s preference, taking into consideration the risks of insertion of a new device. The overall risk of PID following insertion of IUC is low (<1%) [14]. PID is more likely in the 3 weeks following insertion, and in women at risk of STIs. FSRH guidance recommends that STI screening before insertion is only necessary for those at risk of STIs. In the absence of STI results in women deemed at high risk of infection, then prophylactic antibiotics (to cover chlamydia) can be given if insertion is required, for example. Cu‐IUD for emergency contraception. A systematic review concluded that there were no differences in outcomes in IUC users with PID who had the IUC removed or left in situ [16]. If the IUC is removed, then oral emergency contraception should be provided (if required) and alternative ongoing contraception. Actimomyces‐like organisms (ALOs) are commonly identified through cervical screening programmes. ALOs have rarely been associated with severe pelvic infection in IUC users. If a woman with an IUC has ALOs and has no signs or symptoms of infection, then the device can be left in situ or safely removed and another inserted immediately. However, if the woman has symptoms of infection, then removal of the IUC is advised along with treatment with antibiotics (and testing for STIs) [14]. The overall risk of ectopic pregnancy is much reduced in women using IUC compared with women using less effective methods or no contraception. The absolute risk of ectopic pregnancy is 0.01 per 100 woman‐years (95% CI 0.00–0.003) for 52‐mg LNG‐IUS users, 0.07 per 100 woman‐years (95% CI 0.02–1.78) for Cu‐IUD users and 0.10 per 100 woman‐years (95% CI 0.02–0.29) for 13.5‐mg LNG‐IUS users [14,17,18]. However, if a pregnancy does occur with IUC in situ, then the relative risk of an ectopic increases. In the EURAS study approximately 20% of pregnancies in IUC users were ectopic [14]. An ultrasound scan should be conducted in pregnant women with an IUC to exclude ectopic pregnancy. IUC should be removed before 12 weeks’ gestation in view of the greater risk of miscarriage, preterm delivery and chorioamnionitis if left in situ. The endometrial effects of the Cu‐IUD tend to cause increased menstrual bleeding and dysmenorrhoea. Conversely, women can be advised that a reduction in menstrual blood loss and an increase in amenorrhoea can be expected over the first year of use with the LNG‐IUS. Amenorrhoea rates with the 19.5 mg LNG‐IUS and the 13.5‐mg LNG‐IUS are less than with the 52‐mg LNG‐IUS (18.9%, 12.7% vs. 23.6% amenorrhoea at 3 years, respectively) [17]. Frequent and prolonged spotting is common with the LNG‐IUS, particularly in the first months of use. Careful counselling about menstrual irregularities is vital to avoid premature discontinuation. When abnormal bleeding patterns occur with IUC, gynaecological causes should be excluded. Pelvic examination, pregnancy testing and STI testing should be considered. In addition, ultrasound and/or endometrial biopsy (especially in women over the age of 45) should also be considered if abnormal bleeding is persistent or is associated with other features such as pain/dyspareunia [19]. Addition of a non‐steroidal anti‐inflammatory drug (NSAID) or antifibrinolytic (tranexamic acid) may reduce menstrual blood loss with the Cu‐IUD. Alternatively, Cu‐IUD users may consider switching to a LNG‐IUS. Hormonal side effects associated with the LNG‐IUS are likely to decrease with time. A systematic review failed to demonstrate any differences in side‐effect profile between the 52‐mg LNG‐IUS and Cu‐IUD. Side‐effect profile of the 13.5‐mg LNG‐IUS is similar to that of the 52‐mg LNG‐IUS [20]. Effects of hormonal contraception on libido are difficult to study because of the multiple factors that influence libido. Existing evidence fails to show that the LNG‐IUS has negative effects on libido. Weight gain has been reported in users of both Cu‐IUD and LNG‐IUS, but this does not appear to differ between these methods [20]. IUC can be fitted at any point in the cycle provided it is reasonably certain the woman is not pregnant. A Cu‐IUD will be effective immediately for contraception. No additional precautions are required if the LNG‐IUS is fitted on day 1–7 of the cycle, and 7 days of additional contraceptive precautions (condoms/abstinence) are recommended if fitted later than this time [14]. Insertion of IUC can take place as soon as the placenta is delivered at caesarean section or following vaginal delivery (within 10 min of delivery of placenta or up to 48 hours later) (UK MEC 1). A Cochrane review concluded that insertion at this time is safe and effective with no increased risk of perforation or infection compared with insertion weeks later [21]. Post‐placental insertion of IUC can be extremely convenient for women who, due to the constraints and pressures of having a new baby, may be less likely to attend for IUC at a later date. Expulsion rates of IUC devices after vaginal delivery may be higher than at other times (reported from 4 to 38%) [22], but this may be outweighed by advantages of insertion at this time. For women choosing post‐placental insertion of a Cu‐IUD, the bleeding associated with insertion can be masked by lochia; women choosing the LNG‐IUS can benefit immediately from reduced menstrual bleeding [23]. Women who have been fitted with IUC should be provided with clear verbal and written information on what signs and symptoms would indicate a possible complication, how to conduct a self‐check of threads, which device they have in situ and when it needs replacing. Unless pregnancy is desired, removal should only be undertaken during menstruation or if one can be reasonably certain that there is no risk of pregnancy (no unprotected intercourse within 7 days). Progestogen‐only contraception is available in a wide variety of delivery systems including IUS (see above), implants, injectable and oral. It has been less commonly used than combined hormonal contraception and so there are fewer data on the risks associated with long‐term use. All methods of progestogen‐only contraception have a number of mechanisms of action. The implant, injectable and desogestrel‐containing pill inhibit ovulation. Older low‐dose pill formulations inhibit ovulation only inconsistently. All affect cervical mucus, reducing sperm penetrability and transport. The LNG‐IUS has little effect on ovarian activity but causes marked endometrial atrophy, thus compromising implantation if ovulation and fertilization occur. Failure rates for progestogen‐only methods are shown in Table 65.1. The only currently available implant in Europe (Nexplanon®) is a single rod containing 68 mg of 3‐keto‐desogestrel (a metabolite of desogestrel) providing contraception for 3 years. The initial release rate of 60–70 µg/day falls gradually to around 25–30 µg/day at the end of 3 years. The implant is inserted using local anaesthesia, subdermally on the inner aspect of the non‐dominant arm, 8 cm above the elbow. The implant contains a small amount of barium sulfate which facilitates localization by X ‐ray to assist removal if not palpable. In the UK, FSRH certification of competence in insertion and removal techniques for the implant (and for IUC) is recommended [24]. Complications with insertion have been linked to subsequent difficult implant removals and rare cases of intravascular location of implants. Implants that are not palpable should be removed by someone experienced. Up to 20% of implant users experience amenorrhoea. The remainder have regular bleeding, or irregular light unpredictable bleeding. Heavy bleeding is uncommon. Long‐acting depot medroxyprogesterone acetate (DMPA) is available as a formulation that is given by deep intramuscular injection (150 mg) every 13 weeks (Depoprovera®) or as a micronized (104 mg) preparation that is administered subcutaneously (Sayana®) at the same interval. Both have the same efficacy and bleeding pattern, and the same effects on bone and on return to fertility after stopping [25]. The subcutaneous preparation is available in a simple delivery system consisting of a plastic reservoir filled with DMPA with an integral needle attached (Fig. 65.1) and is licensed for self‐administration. Approximately 1 in 10 women may develop some lipoatrophy at the subcutaneous injection site (dimpling or nodule of skin) and should be counselled about this. Fig. 65.1 Subcutaneous depot medroxyprogesterone acetate. The dose of progestogen in DMPA inhibits ovulation and by the end of 1 year of use over 50% of women will have amenorrhoea. Heavy prolonged bleeding may be a problem in around 2% of women [25]. The low dose of second‐generation progestogen (levonorgestrel, norethisterone) does not consistently inhibit ovulation. A progestogen‐only preparation (POP) containing the third‐generation progestogen desogestrel inhibits ovulation in almost every cycle. Around 50% of women using a low‐dose POP continue to ovulate and therefore menstruate regularly, while 10% experience complete suppression of follicular development and have amenorrhoea. The remainder have inconsistent ovulation and bleed irregularly. Almost 50% of women using the desogestrel POP experience amenorrhoea or infrequent bleeding periods, while the rest are likely to have irregular bleeding [26]. If a POP is taken late (>3 hours late for low‐dose pill or >12 hours late for desogestrel pill), then the next pill should be taken, but additional contraceptive protection used for 48 hours (to build up contraceptive effect on cervical mucus) [26]. Progestogen‐only contraception is commonly prescribed for women in whom oestrogen is contraindicated. There are few contraindications to use of these methods. The UK MEC 4 conditions (unacceptable health risk if contraceptive is used) for use of progestogen‐only methods include past breast cancer. A meta‐analysis of data on use of DMPA on acquisition of HIV suggested a moderate increase in risk [27]. The biological basis proposed is a possible effect of DMPA on local immune function, or via vaginal atrophy. A WHO expert group review concluded that data were not sufficiently robust to determine if an association was causal as studies could not exclude important methodological confounders such as non‐use of condoms amongst users of the injectable [28]. The use of DMPA by women at high risk of HIV is therefore a UKMEC 2 [9]. The commonest side effect and cause for discontinuation of a POP is an unacceptable bleeding pattern. Inconsistent ovulation and fluctuating endogenous oestrogen production from irregular follicle growth lead to irregular bleeding. However, there is also evidence to suggest that POPs directly affect the vasculature of the endometrium, increasing the chance of bleeding. Bleeding patterns differ according to the dose of progestogen and the route of administration. It is important to ensure that women with unscheduled bleeding have no underlying gynaecological cause. In such circumstances, the FSRH guideline advises that in women using an injectable, implant or LNG‐IUS may try concomitant use of the combined pill (in medically eligible women) as a short‐term solution [19]. There is also limited evidence that mefenamic acid and tranexamic may reduce the duration of an episode of unscheduled bleeding in women using the injectable or implant [19]. The effect of low‐dose POPs on ovarian activity may result in functional ovarian cysts (persistent follicles). Usually asymptomatic, they can cause abdominal pain or dyspareunia. Most will disappear with menstruation and so treatment should be expectant management. Headache, nausea, bloating, breast tenderness, and weight and mood change are all common in women using and not using hormonal contraception. They often settle with time. A Cochrane review reported that injectable users had a mean weight gain of 3 kg after 2 years of use. Weight gain in adolescents who are new DMPA users is greater in those of greater baseline body mass index (BMI) [29]. Oily skin and acne can be a problem with the more androgenic progestogens such as levonorgestrel and norethisterone. Fertility returns rapidly after stopping low‐dose progestogen‐only contraception. However, it may take up to 1 year for fertility to return following cessation of DMPA which makes DMPA inappropriate for women wishing short‐term contraception. Progestogen‐only methods are much less widely used than the combined methods so data on long‐term risks are sparse. There is no evidence for an increase in the risk of myocardial infarction or stroke in association with progestogen‐only contraception. Although a small number of case–control and retrospective studies suggested that DMPA may be associated with an increased risk of venous thromboembolism (VTE) compared with non‐ users, a causal association has not been demonstrated [30]. Use of DMPA amongst women with risk factors for VTE or a history of VTE is therefore a UK MEC 2. Complete inhibition of ovulation by the injectable DMPA causes hypo‐oestrogenism and amenorrhoea. Hypo‐oestrogenism is associated with a reduction in bone mineral density (BMD). Current use of DMPA is associated with a loss of BMD compared with non‐users. Prospective studies have reported statistically significant decreases in BMD over 2 years amongst DMPA users compared with non‐users [31]. Limited evidence suggests that this bone loss is reversible on stopping. In spite of the effect on BMD, there is no significant association between DMPA use and risk of osteoporotic fracture after adjusting for baseline BMD. The FSRH advises that in women who wish to continue using DMPA, re‐evaluation of the risks and benefits of treatment should be carried out every 2 years. In women with significant lifestyle and/or medical risk factors for osteoporosis, other methods of contraception should be considered.
Contraception and Sterilization
Effectiveness
Method
Typical use
Perfect use
No method
85
85
Calendar
9
Sympto‐thermal
2
Diaphragm
16
6
Female condom
21
5
Male condom
15
2
Combined pill and progestogen‐only pill
8
0.3
Combined hormonal patch
8
0.3
Combined hormonal ring
8
0.3
Injectable (DMPA)
3
0.3
IUD, copper T
0.8
0.6
IUS (Mirena)
0.1
0.1
Implant
0.05
0.05
Female sterilization
0.5
0.5
Male sterilization
0.15
0.10
Medical eligibility for contraception
UK MEC
Definition of category
1
A condition for which there is no restriction for use of the contraceptive method
2
A condition where the advantages of using the method generally outweigh the theoretical or proven risks
3
A condition where the theoretical or proven risks generally outweigh the advantages of using the method. The provision of a method requires expert clinical judgement and/or referral to a specialist contraceptive provider, since use of the method is not usually recommended unless other more appropriate methods are not available or not acceptable
4
A condition which represents an unacceptable health risk if the contraceptive method is used
Contraceptive choice
Intrauterine contraception
Efficacy
Mechanism of action
Contraindications
Risks
Perforation
Expulsion
Infection
Ectopic pregnancy
Side effects
Menstrual disturbance
Mood, weight and libido
Timing of insertion
Postpartum IUC insertion
Post‐insertion instructions
Progestogen‐only contraception
The methods
Subdermal implants
Injectable
Oral
Indications and contraindications
Side effects
Bleeding disturbances
Persistent follicles/follicular cysts
Other ‘hormonal’ side effects
Delay in the resumption of fertility
Serious side effects
Cardiovascular disease
Bone mineral density
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