Emergency contraception Health Dictionary

A sudden unexpected onset of illness or injury which requires immediate care.... emergency

A means of avoiding pregnancy despite sexual activity. There is no ideal contraceptive, and the choice of method depends on balancing considerations of safety, e?ectiveness and acceptability. The best choice for any couple will depend on their ages and personal circumstances and may well vary with time. Contraceptive techniques can be classi?ed in various ways, but one of the most useful is into ‘barrier’ and ‘non-barrier’ methods.

Barrier methods These involve a physical barrier which prevents sperm (see SPERMATOZOON) from reaching the cervix (see CERVIX UTERI). Barrier methods reduce the risk of spreading sexually transmitted diseases, and the sheath is the best protection against HIV infection (see AIDS/HIV) for sexually active people. The e?ciency of barrier methods is improved if they are used in conjunction with a spermicidal foam or jelly, but care is needed to ensure that the preparation chosen does not damage the rubber barrier or cause an allergic reaction in the users. CONDOM OR SHEATH This is the most commonly used barrier contraceptive. It consists of a rubber sheath which is placed over the erect penis before intromission and removed after ejaculation. The failure rate, if properly used, is about 4 per cent. DIAPHRAGM OR CAP A rubber dome that is inserted into the vagina before intercourse and ?ts snugly over the cervix. It should be used with an appropriate spermicide and is removed six hours after intercourse. A woman must be measured to ensure that she is supplied with the correct size of diaphragm, and the ?t should be checked annually or after more than about 7 lbs. change in weight. The failure rate, if properly used, is about 2 per cent.

Non-barrier methods These do not provide a physical barrier between sperm and cervix and so do not protect against sexually transmitted diseases, including HIV. COITUS INTERRUPTUS This involves the man’s withdrawing his penis from the vagina before ejaculation. Because some sperm may leak before full ejaculation, the method is not very reliable. SAFE PERIOD This involves avoiding intercourse around the time when the woman ovulates and is at risk of pregnancy. The safe times can be predicted using temperature charts to identify the rise in temperature before ovulation, or by careful assessment of the quality of the cervical mucus. This method works best if the woman has regular menstrual cycles. If used carefully it can be very e?ective but requires a highly disciplined couple to succeed. It is approved by the Catholic church.

SPERMICIDAL GELS, CREAMS, PESSARIES, ETC.

These are supposed to prevent pregnancy by killing sperm before they reach the cervix, but they are unreliable and should be used only in conjunction with a barrier method.

INTRAUTERINE CONTRACEPTIVE DEVICE (COIL) This is a small metal or plastic shape, placed inside the uterus, which prevents pregnancy by disrupting implantation. Some people regard it as a form of abortion, so it is not acceptable to all religious groups. There is a risk of pelvic infection and eventual infertility in women who have used coils, and in many countries their use has declined substantially. Coils must be inserted by a specially trained health worker, but once in place they permit intercourse at any time with no prior planning. Increased pain and bleeding may be caused during menstruation. If severe, such symptoms may indicate that the coil is incorrectly sited, and that its position should be checked. HORMONAL METHODS Steroid hormones have dominated contraceptive developments during the past 40 years, with more than 200 million women worldwide taking or having taken ‘the pill’. In the past 20 years, new developments have included modifying existing methods and devising more e?ective ways of delivering the drugs, such as implants and hormone-releasing devices in the uterus. Established hormonal contraception includes the combined oestrogen and progesterone and progesterone-only contraceptive pills, as well as longer-acting depot preparations. They modify the woman’s hormonal environment and prevent pregnancy by disrupting various stages of the menstrual cycle, especially ovulation. The combined oestrogen and progesterone pills are very e?ective and are the most popular form of contraception. Biphasic and triphasic pills contain di?erent quantities of oestrogen and progesterone taken in two or three phases of the menstrual cycle. A wide range of preparations is available and the British National Formulary contains details of the commonly used varieties.

The main side-e?ect is an increased risk of cardiovascular disease. The lowest possible dose of oestrogen should be used, and many preparations are phasic, with the dose of oestrogen varying with the time of the cycle. The progesterone-only, or ‘mini’, pill does not contain any oestrogen and must be taken at the same time every day. It is not as e?ective as the combined pill, but failure rates of less than 1-per-100 woman years can be achieved. It has few serious side-effects, but may cause menstrual irregularities. It is suitable for use by mothers who are breast feeding.

Depot preparations include intramuscular injections, subcutaneous implants, and intravaginal rings. They are useful in cases where the woman cannot be relied on to take a pill regularly but needs e?ective contraception. Their main side-e?ect is their prolonged action, which means that users cannot suddenly decide that they would like to become pregnant. Skin patches containing a contraceptive that is absorbed through the skin have recently been launched.

HORMONAL CONTRACEPTION FOR MEN There is a growing demand by men worldwide for hormonal contraception. Development of a ‘male pill’, however, has been slow because of the potentially dangerous side-effects of using high doses of TESTOSTERONE (the male hormone) to suppress spermatogenesis. Progress in research to develop a suitable ANDROGEN-based combination product is promising, including the possibility of long-term STEROID implants. STERILISATION See also STERILISATION – Reproductive sterilisation. The operation is easier and safer to perform on men than on women. Although sterilisation can sometimes be reversed, this cannot be guaranteed and couples should be counselled in advance that the method is irreversible. There is a small but definite failure rate with sterilisation, and this should also be made clear before the operation is performed. POSTCOITAL CONTRACEPTION Also known as emergency contraception or the ‘morning after pill’, postcoital contraception can be e?ected by two di?erent hormonal methods. Levonorgesterol (a synthetic hormone similar to the natural female sex hormone PROGESTERONE) can be used alone, with one pill being taken within 72 hours of unprotected intercourse, but preferably as soon as possible, and a second one 12 hours after the ?rst. Alternatively, a combined preparation comprising ETHINYLESTRADIOL and levonorgesterol can be taken, also within 72 hours of unprotected intercourse. The single constituent pill has fewer side-effects than the combined version. Neither version should be taken by women with severe liver disease or acute PORPHYRIAS, but the ethinylestradiol/levonorgesterol combination is unsuitable for women with a history of THROMBOSIS.

In the UK the law allows women over the age of 16 to buy the morning-after pill ‘over the counter’ from a registered pharmacist.... contraception

See contraception, emergency.... postcoital contraception

Accident and Emergency Medicine is the specialty responsible for assessing the immediate needs of acutely ill and injured people. Urgent treatment is provided where necessary; if required, the patient’s admission to an appropriate hospital bed is organised. Every part of the UK has nominated key hospitals with the appropriately trained sta? and necessary facilities to deal with acutely ill or injured patients. It is well-recognised that prompt treatment in the ?rst hour or so after an accident or after the onset of an acute illness – the so-called ‘golden hour’ – can make the di?erence between the patient’s recovery and serious disability or death.

A&E Medicine is a relatively new specialty in the UK and there are still inadequate numbers of consultants and trainees, despite an inexorable rise in the number of patients attending A&E departments. With a similar rise in hospital admissions there is often no bed available immediately for casualties, resulting in backlogs of patients waiting for treatment. A major debate in the specialty is about the likely need to centralise services by downgrading or closing smaller units, in order to make the most e?cient use of sta?.

See www.baem.org.uk... accident and emergency medicine

A system allowing an older person to be linked for up to 24 hours a day to a central service which can offer help in an emergency.... emergency alarm

Service provided in response to the perceived individual need for immediate treatment or care.... emergency service

Action taken to prevent CONCEPTION after sexual intercourse. The type of contraception may be hormonal, or it may be an intrauterine device (see below, and under CONTRACEPTION). Pregnancy after intercourse without contraception – or where contraception has failed as a result, for example, of a leaking condom – may be avoided with a course of ‘morning-after’ contraceptive pills. Such preparations usually contain an oestrogen (see OESTROGENS) and a PROGESTOGEN. Two doses should be taken within 72 hours of ‘unprotected’ intercourse. An alternative for the woman is to take a high dose of oestrogen on its own. The aim is to postpone OVULATION and to affect the lining of the UTERUS so that the egg is unable to implant itself.

Intrauterine contraceptive device (IUCD) This, in e?ect, is a form of post-coital contraception. The IUCD is a plastic shape up to 3 cm long around which copper wire is wound, carrying plastic thread from its tail. Colloquially known as a coil, it acts by inhibiting implantation and may also impair migration of sperm. Devices need changing every 3–5 years. Coils have generally replaced the larger, non-copper-bearing ‘inert’ types of IUCD, which caused more complications but did not need changing (so are sometimes still found in situ). They tend to be chosen as a method of contraception (6 per cent) by older, parous women in stable relationships, with a generally low problem rate.

Nevertheless, certain problems do occur with IUCDs, the following being the most common:

They tend to be expelled by the uterus in women who have never conceived, or by a uterus distorted by, say, ?broids.

ECTOPIC PREGNANCY is more likely.

They are associated with pelvic infection and INFERTILITY, following SEXUALLY TRANSMITTED DISEASES (STDS) – or possibly introduced during insertion.

They often produce heavy, painful periods (see MENSTRUATION), and women at high risk of these problems (e.g. women who are HIV positive [see AIDS/HIV], or with WILSON’S DISEASE or cardiac lesions) should generally be excluded – unless the IUCD is inserted under antibiotic cover.... post-coital contraception

Measures to avoid pregnancy following unprotected sexual intercourse. There are 2 main methods: hormonal and physical. In the first, oral contraceptives (the “morning after” pill) are taken in a high dose as soon as possible, but not longer than 72 hours, after unprotected intercourse, with a second dose taken 12 hours later. They may be given as a high-dose progesterone-only pill or as a high-dose combined (oestrogen and progesterone) pill. In the physical method, an IUD is inserted by a doctor within 5 days of unprotected intercourse.... contraception, emergency

The use by women of synthetic progestogen drugs, which are often combined with synthetic oestrogens, to prevent pregnancy.

These drugs suppress ovulation and make cervical mucus thick and impenetrable to sperm.

They also cause thinning of the endometrium (lining of the uterus), which reduces the chance of a fertilized egg implanting successfully.

The best-known form of hormonal contraception is the contraceptive pill (see oral contraceptives).

The hormones can also be given as contraceptive implants under the skin, by injection (see contraceptives, injectable), or be released by IUDs.... contraception, hormonal methods of

See coitus interruptus.... contraception, withdrawal method of

See contraception, natural methods of.... mucus method of contraception

accident and emergency medicine: an important specialty dealing with the immediate problems of the acutely ill and injured. See also ED.... accident and emergency medicine

see HEMS.... helicopter-based emergency medical services

(MET) a team, usually consisting of a group of physicians, anaesthetists, and senior nurses, that can be summoned urgently to attend to patients with deteriorating medical conditions. The aim is to prevent further deterioration and to decide if enhanced levels of care are appropriate (e.g. on the high-dependency or intensive care units). The team will also assume the role of the *cardiac-arrest team.... medical emergency team

Methods of avoiding conception based on attempts to pinpoint a woman’s fertile period around the time of ovulation, so that sexual intercourse can be avoided at this time. The calendar method is based on the assumption that ovulation occurs around 14 days before menstruation. Because of its high failure rate, it has been largely superseded by other methods. The temperature method is based on the normal rise of a woman’s body temperature in the second half of the menstrual cycle, after ovulation has occurred. The woman takes her temperature daily using an ovulation thermometer. Sex is considered to be only safe after there has been a sustained temperature rise for at least 3 days.

The cervical mucus method attempts to pinpoint the fertile period by observing and charting the amount and appearance of cervical mucus during the menstrual cycle.

Recognized changes in the mucus occur before and often at ovulation.

The symptothermal method combines the temperature and cervical mucus methods.... contraception, natural methods of