1: CONTRACEPTION

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CHAPTER 1 CONTRACEPTION

INTRODUCTION

The practice nurse with family planning training may play a significant role, e.g. diaphragm-fitting, pill-teaching and coil-checking.

Methods of contraception include: combined pills, progestogen-only pills, injectable and implanted progestogens, condoms, diaphragms, intrauterine contraceptive devices, natural methods and surgical sterilisation. Other methods, e.g. coitus interruptus, the use of spermicides alone and contraceptive sponges, are not discussed in this chapter as their failure rates are relatively high. Long-acting reversible contraceptive methods (IUD, IUS, depot injections and implants) are more cost-effective than the COC. All contraceptives, other than condoms, are available free on prescription.

Discussion of ‘safe sex’ and the prevention of HIV infection and other sexually transmitted infections should be part of the routine advice given to the sexually active. This is particularly important when counselling the very young. (Surveys suggest that about 50% of all under-16-year-old females have had intercourse.) ‘Safe sex’ means sex in which the exchange of bodily fluids is eliminated. ‘Low-risk sex’ means wet kissing, oral sex without ejaculation, and sexual intercourse using a condom. The use of the condom should be promoted in addition, often, to the main contraceptive. The advantages of fidelity within a sexual relationship, and, in the very young, of postponing intercourse, should be discussed in a non-judgemental way.

Always consider the possible STI risk when discussing contraception, particularly in the following situations:

• Young patient/early in sexual career.

• Emergency contraception request.

• IUCD request.

• TOP request.

• Patient symptomatic (pain, discharge, ulcers, intermenstrual bleeding, postcoital bleeding, breakthrough bleeding on COC, contact bleeding on taking cervical smear).

• Multiple partners or recent change of partner.

• Partner symptomatic.

FRASER GUIDELINES

A doctor must consider the following issues when the patient is under 16 years old:

• Whether the patient understands the potential risks and benefits of the treatment and the advice given.

• The value of parental support. Doctors must encourage young people to inform parents of the consultation and explore the reasons if the patient is unwilling to do so. The patient must be assured of confidentiality.

• Whether the patient is likely to have sexual intercourse without contraception.

• Whether the patient’s physical or mental health is likely to suffer if s/he does not receive contraceptive advice or supplies.

• Whether the patient’s best interests would require the provision of contraceptive advice or supplies, or both, without parental consent.

COMBINED ORAL CONTRACEPTIVE (COC)

STARTING THE COC

Assessment

Examination.

• smear status.

Management

The following points should be considered and discussed, if appropriate:

Failure rate.

The failure rate is in the range 0.1–3/100 women-years.

How to start the COC

• Start on day 1 to 5 and no extra contraceptive precautions are necessary.

• Alternatively, start after day 5 and take extra precautions for the first 7 days. (The COC may in fact be started on any day of the cycle, provided that extra precautions are taken for 7 days, but initial bleeding will be unpredictable.)

• Take 1 tablet daily for 21 days. Subsequent courses repeated after 7-day pill-free interval.

Ovulation.

The COC stops ovulation; ‘periods’ are light withdrawal bleeds.

Risks of taking the COC

• Smoking >15 cigarettes per day increases the risk of coronary heart disease by three times.

• Vascular disease in general is increased by about three times. (There is no statistically significant increased risk of myocardial infarction among pill users, unless they also smoke.)

• Hypertension develops in 5% of pill users after 5 years.

• There is a 1.2 relative increase of carcinoma of the breast during use and for 10 years after stopping the COC; this does not appear to be related to duration of use. It is more than counterbalanced by the protective effect against cancers of the ovary and endometrium.

Side-effects

• Breakthrough bleeding. (This usually settles within 2–3 months.)

• Nausea, breast tenderness, weight gain, PMT, bloating (fluid retention), depression, vaginal discharge (secondary to cervical erosion), headaches, reduced libido, chloasma.

Gastrointestinal upset.

Vomiting and severe diarrhoea lead to reduced hormone absorption. Take extra contraceptive precautions for the period of illness and for 7 days afterwards.

Prescribing.

Ideally, use the lowest strength of pill that does not cause breakthrough bleeding. The dose of oestrogen (ethinyloestradiol) should normally be no more than 20–35μg. Ideally, a preparation with the lowest oestrogen and progestogen content which gives good cycle control and minimal side-effects should be chosen.

Low strength preparations (containing ethinyloestradiol 20μg) are particularly appropriate for women with risk factors for circulatory disease.

Standard strength preparations (containing ethinyloestradiol 30 or 35μg) are appropriate for standard use.

Reproduced with permission from Guillebaud J 2004 Contraception: your questions answered, 4th edn. Churchill Livingstone, Edinburgh

Phased preparations are particularly appropriate for women who either do not have withdrawal bleeds or who have BTB with monophasic pills.

Common choices for women free of risk factors for arterial disease under the age of 30 years are pills delivering levonorgestrel or norethisterone. Women with risk factors for arterial disease or those who are relatively intolerant of pills containing levonorgestrel or norethisterone may do better on a pill containing a third-generation progestogen.

Pills containing the third-generation progestogens (desogestrel, gestodene or drospirenone) can also be useful for women who have side-effects (e.g. weight gain, acne, headaches, depression, breast symptoms and BTB) with other progestogens. Desogestrel and gestodene increase the risk of DVT. In 100 000 women, the approximate number developing a DVT in 1 year is:

• for women taking a pill containing desogestrel or gestodene, 25

• for women taking one of the other COCs, 15

• for women who are pregnant, 60

• for other healthy women not taking a COC, 5.

Women with risk factors for venous disease (including women with a BMI of >30, those with marked varicose veins, those with an immobility problem and those with a family history of DVT) should not use these pills.

Drug interactions.

Liver enzyme inducers, e.g. phenytoin, carbamazepine, griseofulvin and topiramate, increase the metabolism, and thus elimination in the bile, of both oestrogen and progestogen. If the patient is on a liver enzyme inducer, start a higher dose pill (≥50 μg oestrogen). Consider ‘tricycling’ (i.e. taking 3 or 4 packets of monophasic tablets without a break followed by a short tablet-free interval of 4 days).

Certain broad-spectrum antibiotics (e.g. ampicillin, tetracyclines and griseofulvin) alter gut flora and reduce oestrogen absorption. Take extra precautions for the duration of treatment and for 7 days afterwards. Long-term treatment with antibiotics does not require extra precautions, as resistant flora develop.

Follow-up.

The first follow-up is at 3 months. Subsequent follow-ups are at 6–12 month intervals.

• new risk factors

• smoking status

• weight change

• smear status.

Management of subsequent problems

Breakthrough bleeding

• Ask about COC compliance or vomiting (prevents COC absorption).

• Liver enzyme inducing drugs (e.g. phenytoin) can cause BTB.

• Consider pregnancy.

• Check for cervical lesions if BTB is persistent.

• (Chlamydia may cause a blood-stained discharge/BTB.)

If BTB persists for >2–3 months after starting the COC, try an equivalent pill with a different progestogen (see pill ladder, p. 5) or a pill with a higher oestrogen or progestogen content or change to a triphasic pill.

Absent withdrawal bleed.

Absent withdrawal bleeds are harmless in themselves. Consider pregnancy. Consider changing to a pill with a lower dose of progestogen or to a triphasic pill.

Side-effects.

As a general rule, for all minor side-effects, reduce the dose where possible (this usually means reducing the dose of the progestogen, as nearly all pill-takers are on 30–35 μg of the oestrogen), or change to a pill containing a different progestogen.

The following side-effects are due to a relative oestrogen excess, and may be alleviated by changing to a progestogen-dominant pill (e.g. Loestrin 30, Microgynon 30 or Eugynon 30):

• cyclical weight gain

• ‘bloating’

• vaginal discharge.

The following side-effects are due to a relative progestogen excess, and may be alleviated by changing to an oestrogen-dominant pill (e.g. Brevinor, Mercilon, Trinordiol, Logynon, Marvelon, Femodene or Dianette):

• vaginal dryness

• sustained weight gain

• loss of libido

• breast tenderness

If headaches occur in the pill-free interval, consider tricycling (taking 3 packs consecutively, thus avoiding the pill-free intervals).

Changing from one pill to another.

If the new pill has the same oestrogen dose or higher than the old pill, start it after a 7-day gap. If the new pill has a lower oestrogen dose than the old pill, start it immediately after the previous pack without a break.

To postpone a period (e.g. for a holiday).

Start the next pack immediately, without a pill-free interval. (With phased pills, except Synphase, take the extra pills from the last phase of the new pack. This will postpone the period by the same number of days as there are tablets in the last phase of the pack.)

Stopping the pill to conceive.

Ideally, use an alternative method of contraception for 3 months and until one natural period has passed. Preconceptual counselling is important (see p. 22).

COMBINED CONTRACEPTIVE TRANSDERMAL PATCH

Indications (in view of expense)

• Women who comply poorly with COC.

• Women who work difficult shifts or travel between time zones frequently.

Releases ethinyloestradiol 20 μg and norelgestromin 150 μg daily. One patch per week for 3 weeks and 7 patch-free days. Similar efficacy and contraindications to COC.

PROGESTOGEN-ONLY PILL (POP)

The POP is particularly useful for the following:

• Older women – especially those over 35 years old who smoke. (In women over 40 years old the POP is as effective as the COC.) It can relieve PMT and climacteric symptoms.

• Lactating women.

• Women in whom the COC is contraindicated by e.g. hypertension, diabetes, migraine, thrombosis and embolus.

• Women with troublesome oestrogenic side-effects from the COC, e.g. fluid retention, cyclical weight gain, headache and chloasma.

• Women awaiting major surgery.

STARTING THE POP

Management

The following points should be considered and discussed.

Failure rate.

The overall failure rate is in the range 0.3–4/100 woman-years.

Irregular bleeding or amenorrhoea.

These may occur. Most women have a cycle of between 25 and 35 days. The blood loss is light.

Drug interactions.

Efficacy is reduced by enzyme-inducing drugs.

Antibiotics do not affect the POP.

How to start the POP

• Start on day 1 (the first day of the period) and no extra contraceptive precautions are necessary.

• If starting in mid-cycle, take extra precautions for the first 7 days.

• If changing from a COC, start the POP immediately, without a 7-day gap. No extra precautions are necessary.

• Take the POP regularly every day (no breaks) at the same time, within 2–3 hours. It is maximally effective 5 hours after taking it. If a couple normally have intercourse in the morning, the POP should ideally be taken in the evening.

What to do if a pill is missed

Take it as soon as it is remembered and carry on with the next pill at the right time. If a pill is taken more than 3 hours late (12 hours for Cerazette), protection may be lost. Continue normal pill-taking and take extra contraceptive precautions for 48 hours. Emergency (oral or IUCD) postcoital contraception (see p. 11) should be offered after any unprotected intercourse which occurs during the 7 days after missing 1 pill by more than 3 hours.

Complications.

There is an increased incidence of ectopic pregnancies.

Side-effects.

Breakthrough bleeding, nausea, breast tenderness, acne, weight gain, loss of libido, depression. These often settle after 2–3 months.

Vomiting and severe diarrhoea.

In the event of these symptoms, continue normal pill-taking and take extra precautions for the period of illness and for 7 days afterwards.

Follow-up.

The first follow-up is at 3 months. Subsequent follow-ups are at 6–12 month intervals.

• new risk factors

• weight change

• smear status.

INJECTABLE PROGESTOGENS

Injectable progestogens inhibit ovulation. The failure rate is 0–2/100 woman-years. The contraindications are as for the POP. They are especially useful for forgetful pill-takers in whom other methods may be inappropriate or contraindicated. The main disadvantage is that the method is irreversible for at least 3 months, and early side-effects may therefore have to be tolerated for this length of time.

The main side-effects are (as for the POP):

• breakthrough bleeding

• amenorrhoea with delay in return to fertility for up to 1 year

• weight gain.

Depo-Provera reduces bone mineral density in many women who use it. This reduction occurs in the first 2–3 years of use and then stabilises. In adolescents, Depo-Provera should only be used when other methods of contraception are inappropriate. Consider other methods of contraception in women with risk factors for osteoporosis (see p. 243). Formally re-evaluate women who have used Depo-Provera for more than 2 years.

The usual treatment is 150 mg Depo-Provera im every 12–13 weeks. The second choice injectable progestogen is Noristerat which is given every 8 weeks. The first injection should be given within the first 5 days of the cycle to give immediate contraceptive effect.

Late injections.

The only reason for not giving an injection is a possibility that the woman has already conceived. Consider emergency contraception (see below), if appropriate, with the next injection. Pregnancy must otherwise be excluded before the next injection.

PROGESTOGEN-RELEASING IMPLANT (IMPLANON)

This etonogestrel-releasing single flexible rod is inserted subdermally into the lower surface of the upper arm. Special training is required, although the technique is not difficult.

• It should be inserted during the first 5 days of the cycle to give immediate contraceptive effect.

• It is effective for up to 3 years. In women with a BMI >35 it should be replaced after 2 years.

• The side-effects and contraindications are as for the POP.

• The contraceptive effect is immediately reversible on removal of the implant.

POSTCOITAL (EMERGENCY) CONTRACEPTION

Postcoital contraception is sometimes needed as an emergency measure to prevent pregnancy when unprotected intercourse has put the woman at risk.

HORMONAL EMERGENCY CONTRACEPTION

Management

Advice

Hormonal postcoital contraception is effective for up to 72 hours after intercourse, in preventing implantation (60% of pregnancies are prevented when treatment is given between 72 and 120 hours after UPSI (unlicensed use)).

• The failure rate is 1–2%.

• The sooner it is started after unprotected intercourse, the greater the efficacy.

• Nausea occurs occasionally. If vomiting occurs within 2 hours of taking it, a further dose should be taken together with an antiemetic.

• The next period may be early or late.

• Barrier methods should be used until the next period.

• Discuss future contraception.

• There is no known teratogenic effect if the method fails.

• A pill taker should continue to take her usual pills in the normal way and be warned that she may get spotting in that cycle.

• This method may be used more than once in any one cycle.

• Available OTC for those aged 16 or over.

Prescribing.

Levonorgestrel 1.5 mg as a single dose. Also available OTC.

Follow-up.

This is not usually necessary. It may be arranged 1 month later in order to establish that the patient is not pregnant. Discuss future contraception.

EMERGENCY IUCD

Assessment

History.

• contraindications: the majority of general contraindications to the IUCD apply (see p. 14). However, the IUCD can be used for postcoital contraception in women with a past history of an ectopic pregnancy, in nulliparous women and in women with a recent history of pelvic inflammatory disease (providing antibiotic cover is given)

• normal menstrual cycle

• times of all unprotected intercourse during the present cycle

• present method of contraception.

Management

Advice

• The IUCD can be fitted up to 5 days after unprotected intercourse or up to 5 days after the most probable calculated date of ovulation, e.g. day 19 of a regular 28-day cycle.

• It can be removed after the next period or kept for long-term contraception, if appropriate.

DIAPHRAGM

The failure rate of the diaphragm is about 4/100 woman-years.

At the initial fitting, check the smear status. Advise the woman to practise insertion at home and, if appropriate, to use the diaphragm during intercourse with additional contraception until the first follow-up.

Administration

Prescribe the device and a spermicide on FP10. The cost and administration of the diaphragm can be claimed from the PPA.

INTRAUTERINE CONTRACEPTIVE DEVICE (IUCD)

The failure rate of the IUCD is in the range 0.3–2/100 woman-years. It renders the endometrium unsuitable for implantation.

Management

Insertion.

Insertion should be in the first 14 days of the cycle and the contraceptive effect is immediate.

Women at high risk of Chlamydia infection should be screened (see p. 46). Take swabs for Chlamydia and await results before inserting IUCD, if possible. Those at high risk:

• age <25 years

• more than one sexual partner in the preceding 12 months

• emergency IUCD request

• previous STI

• symptoms of infection.

Advice

• The patient should check the threads weekly for 6 weeks, and monthly thereafter, ideally right at the end of a period.

• Warn the patient about crampy pains for 2–3 days after insertion.

• Tampons can be used.

• Irregular spotting may occur in the first cycle.

• Periods may be heavier and more prolonged.

• Any normal discharge may be heavier.

• Menstrual irregularity and pelvic pain require exclusion of an ectopic pregnancy.

Follow-up.

At 6 weeks, and then annually:

• Check threads.

• Check smear status.

• Exclude anaemia, if appropriate.

• Consider replacement/alternative contraception, if appropriate.

Main disadvantages of IUCDs

• Dysmenorrhoea and menorrhagia (especially in the first 3 months).

• Pelvic infection (see p. 45).

• Perforation.

• Lost threads. If the threads are lost, exclude pregnancy and advise temporary alternative contraception. The device may be within the uterus, have perforated the uterus or have been expelled. Try retrieving the threads by inserting Spencer–Wells forceps into the endocervical canal. If unsuccessful, arrange an ultrasound. If the IUCD is seen to be in the uterine cavity and does not need changing, leave in situ. Arrange gynaecological assessment, if appropriate.

• Intrauterine pregnancy. If the IUCD is in situ, there is an increased risk of miscarriage and, therefore, of infection. The risk can be reduced if the IUCD is gently removed as early as possible. If the pregnancy is >12 weeks, refer to an obstetrician.

• Ectopic pregnancy. (1 in 10–20 pregnancies occurring with the IUCD are extrauterine.) The patient should be advised to report pelvic pain or abnormal bleeding.

Removal.

All coils are licensed for 5 years’ use (the T Safe 380 A is licensed for 8 years). They should be removed during a period or following 7 days abstinence or protected intercourse. If an IUCD is fitted in a woman over the age of 40, it may remain in the uterus until the menopause.

If the woman is planning a pregnancy, she should delay conception until 1 month after removal of the IUCD to allow time for normal endometrium to regenerate.

The IUCD should be removed 2 years after the menopause in women under the age of 50 years, and 1 year after the menopause in women over the age of 50 years.

If the IUCD is removed intermenstrually, alternative contraception should be used for 7 days prior to removal.

INTRAUTERINE PROGESTOGEN-ONLY SYSTEM (MIRENA/IUS)

This is highly effective, with a failure rate of 0.2/100 woman-years. It results in a lower ectopic pregnancy rate than in women using no method. It usually leads to oligomenorrhoea or amenorrhoea, and is therefore suitable for women with heavy periods. Dysmenorrhoea and the risk of pelvic infection are reduced, compared to normal. It is suitable for nulliparous women as well as those who have had children. It is effective for 5 years. Return of fertility is rapid after removal. Fitting should be in the first 14 days of the cycle. If fitted after day 7 of the cycle, condoms should be used for the following 7 days.

Insertion is more painful than with standard IUCDs in view of an inserter of greater diameter, and intermenstrual spotting is a common problem in the early months of use. Spotting may occasionally continue for up to 6 months.

The IUS can be combined with systemic oestrogen for relief of menopausal symptoms, providing endometrial protection and effective contraception for perimenopausal women.

NATURAL BIRTH CONTROL

CALENDAR METHOD

This should only be considered when periods are regular. The period of abstinence required is often long. In a 28-day cycle, ovulation is around day 14 and the fertile period is between days 8 and 17. The released ovum survives for 1 day. The sperm survives for up to 6 days within the female body.

Method of calculation

• Define the shortest and longest menstrual cycle over the previous 12 months.

• To derive the first day of the fertile period, subtract 20 from the length of the shortest cycle. (14 days = maximum length of a luteal phase; 6 days = maximum sperm survival.)

• To derive the last day of the fertile period, subtract 11 from the length of the longest cycle. (12 days = minimum length of a luteal phase; 1 day = maximum ovum survival.)

This method has a high failure rate, even with good compliance.

PERSONA

This machine is available over the counter. The woman’s hormone profile is analysed using daily urine testing strips, giving an indication of the ‘safe period’.

MUCOTHERMAL METHOD

Intercourse should be confined to between 72 hours following the detection of ovulation and the onset of the next menstrual period. Ovulation can be detected by:

• a rise in basal body temperature

• thinning of cervical mucus (Billing’s method).

STERILISATION

Both partners must accept that surgical sterilisation should be considered to be irreversible. Sterilisation should not be performed immediately postpartum or post-TOP, as regret is more likely if the decision is made at a time of stress.

The failure rate of sterilisation is about 0.2/100 woman-years.

Administration

The patient should sign a consent form, as appropriate.

HORMONAL CONTRACEPTION IN THE PERIMENOPAUSE

Contraception should be continued for 1 year after the LMP in women over the age of 50 years, and for 2 years in women under the age of 50.

THE COC

Women who smoke and those with other cardiovascular risk factors should stop the COC at the age of about 35. Fit, normotensive non-smokers with no family history of cardiovascular disease may continue the COC until the age of 50 (consider a 20 μg oestrogen pill, as the absolute risk of cardiovascular disease and breast cancer increases with age).

Synthetic oestrogens in the COC reduce perimenopausal symptoms.

THE POP

The POP does not usually disguise the menopause. Vasomotor symptoms may occur while taking it and the serum FSH may be raised. The failure rate in older women is minimal and is equivalent to the COC in younger women.

In order to establish whether or not natural periods have ceased, stop the COC/POP and use non-hormonal contraception:

• The onset of vasomotor symptoms together with amenorrhoea indicates the menopause, and contraception only needs to be continued for 1 year if over 50 or 2 years if under 50.

• If periods return, the COC/POP may be resumed. (Whether amenorrhoea occurs or periods return, HRT may be started with non-hormonal contraception, if appropriate.)

• Two FSH levels of >30 IU/l, 3 months apart, indicate the menopause.

Related

Churchills Pocketbook of General Practice